Co-reporter:Krishnendu Aich;Sangita Das;Chitrangada Das Mukhopadhyay;Ching Kheng Quah;Hoong-Kun Fun
Inorganic Chemistry August 3, 2015 Volume 54(Issue 15) pp:7309-7315
Publication Date(Web):July 20, 2015
DOI:10.1021/acs.inorgchem.5b00784
On the basis of the Förster resonance energy transfer mechanism between rhodamine and quinoline–benzothiazole conjugated dyad, a new colorimetric as well as fluorescence ratiometric probe was synthesized for the selective detection of Cd2+. The complex formation of the probe with Cd2+ was confirmed through Cd2+-bound single-crystal structure. Capability of the probe as imaging agent to detect the cellular uptake of Cd2+ was demonstrated here using living RAW cells.
Co-reporter:Abhishek Manna;Dibyendu Sain;Nikhil Guchhait
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 23) pp:14266-14271
Publication Date(Web):2017/11/20
DOI:10.1039/C7NJ03079G
A new FRET-based carbazole rhodamine hybrid (CRH) ratiometric fluorescent sensor is reported for the selective detection of Al3+. The design of the probe involved two parts: a carbazole hydrazone energy donor and a rhodamine spirolactone unit (potential rhodamine monoanion energy receptor). First, the emission of the carbazole chromophore (“donor” moiety) and next the absorption of the ring-opened rhodamine dye were measured, which clearly showed the overlap between these two spectra, indicating the FRET from the carbazole chromophore to the rhodamine moiety. FRET based ratiometric live-cell imaging for Al3+ has been rarely reported. Successful live cell imaging is demonstrated, where on addition of Al3+ solution (20 μL), the color of the CRH (20 μL) treated cells changed from blue to red.
Co-reporter:Abhishek Manna;Dibyendu Sain;Nikhil Guchhait
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 23) pp:14266-14271
Publication Date(Web):2017/11/20
DOI:10.1039/C7NJ03079G
A new FRET-based carbazole rhodamine hybrid (CRH) ratiometric fluorescent sensor is reported for the selective detection of Al3+. The design of the probe involved two parts: a carbazole hydrazone energy donor and a rhodamine spirolactone unit (potential rhodamine monoanion energy receptor). First, the emission of the carbazole chromophore (“donor” moiety) and next the absorption of the ring-opened rhodamine dye were measured, which clearly showed the overlap between these two spectra, indicating the FRET from the carbazole chromophore to the rhodamine moiety. FRET based ratiometric live-cell imaging for Al3+ has been rarely reported. Successful live cell imaging is demonstrated, where on addition of Al3+ solution (20 μL), the color of the CRH (20 μL) treated cells changed from blue to red.
Co-reporter:Abhishek Manna;Kanyashree Jana;Nikhil Guchhait
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 14) pp:6661-6666
Publication Date(Web):2017/07/10
DOI:10.1039/C7NJ00598A
Herein, for the fluorogenic and naked eye detection and discrimination of the environmentally and biologically important tabun mimic diethyl cyano phosphonate (DCNP) and sarin mimic diethyl chloro phosphate (DCP) in one platform, a smart probe was designed and synthesized. 2-(2′-Hydroxyphenyl)-benzothiazole (HBT) was fused with fluorescein hydrazide (PET-coupled 2-way-ESIPT system) for this purpose, but the response obtained was just off–on type. Among the metal ions, the receptor can easily detect Zn2+ from other common metal ions. When we used the FHC–Zn2+ complex for the discrimination of DCNP from DCP, the result was very satisfactory. FHC–Zn2+ complex can detect DCP in a ratiometric manner and DCNP in an off–on manner. In this method, under UV light, it is possible to distinguish the color change with the naked eye. The sensing mechanism has been explained via Zn2+-triggered PET-decoupled ESIPT processes. Vapour phase sensing was also performed to show the potential for the real applications of the probe.
Co-reporter:Abhishek Manna;Kanyashree Jana;Nikhil Guchhait
New Journal of Chemistry (1998-Present) 2017 vol. 41(Issue 14) pp:6661-6666
Publication Date(Web):2017/07/10
DOI:10.1039/C7NJ00598A
Herein, for the fluorogenic and naked eye detection and discrimination of the environmentally and biologically important tabun mimic diethyl cyano phosphonate (DCNP) and sarin mimic diethyl chloro phosphate (DCP) in one platform, a smart probe was designed and synthesized. 2-(2′-Hydroxyphenyl)-benzothiazole (HBT) was fused with fluorescein hydrazide (PET-coupled 2-way-ESIPT system) for this purpose, but the response obtained was just off–on type. Among the metal ions, the receptor can easily detect Zn2+ from other common metal ions. When we used the FHC–Zn2+ complex for the discrimination of DCNP from DCP, the result was very satisfactory. FHC–Zn2+ complex can detect DCP in a ratiometric manner and DCNP in an off–on manner. In this method, under UV light, it is possible to distinguish the color change with the naked eye. The sensing mechanism has been explained via Zn2+-triggered PET-decoupled ESIPT processes. Vapour phase sensing was also performed to show the potential for the real applications of the probe.
Co-reporter:Avijit Kumar Das, Shyamaprosad Goswami, Gorachand Dutta, Sibaprasad Maity, Tarun kanti Mandal, Kalyani Khanra and Nandan Bhattacharyya
Organic & Biomolecular Chemistry 2016 vol. 14(Issue 2) pp:570-576
Publication Date(Web):15 Oct 2015
DOI:10.1039/C5OB02008E
H2S is shown, for the first time, to play an extraordinary dual role due to its nucleophilicity and reducing property with our single chemosensor, PND [4-(piperidin-1-yl) naphthalene-1,2-dione]. The initial nucleophilic attack via Michael addition (a lower concentration of H2S, blue fluorescence) is followed by the reduction of the 1,2-diketo functionality (a higher concentration of H2S, green fluorescence). This chemosensor, which also shows biological response, is remarkably effective in sensing the same analyte (H2S) at its different concentrations in a relay pathway via a fluorescence “off–on–on” mechanism, and this is also supported by DFT calculation and Cyclic voltammograms.
Co-reporter:Abhishek Manna, Debasish Sarkar, Shyamaprosad Goswami, Ching Kheng Quah and Hoong-Kun Fun
RSC Advances 2016 vol. 6(Issue 62) pp:57417-57423
Publication Date(Web):31 May 2016
DOI:10.1039/C6RA11009F
For ratiometric, fluorogenic and “naked eye” detection of the environmentally and biologically important ions Hg2+ and OCl− in one platform, a 2-(2′-hydroxyphenyl)-benzothiazole (HBT) inserted thiolactam containing a new rhodol system, spirothiolactamized benzothiazole substituted N,N-diethylrhodol (STBR), is designed and synthesized. We can detect Hg2+ and OCl− in solutions by a simple, easy-to-synthesize practical ratiometric chemodosimeter with two different modes of reactions with a low detection limit. The observed color in the presence of Hg2+ or OCl− may arise from the reaction of Hg2+ or OCl− with STBR – the thiolactam moiety is broken and it helps to achieve maximum π–π* conjugation which results in a brilliant red fluorescence. From 1H-NMR and ESI-MS data, it is clear that the modes of the reaction for Hg2+ and OCl− are different. Test strips are also prepared to observe color changes. The sensing phenomena are fruitfully applied for live-cell imaging in Saccharomyces cerevisiae cells (from a short to long time range, 0 min to 120 min). The single crystal X-ray structure of the synthesised ESIPT rhodol moiety is also reported.
Co-reporter:Avijit Kumar Das, Shyamaprosad Goswami, Ching Kheng Quah and Hoong-Kun Fun
RSC Advances 2016 vol. 6(Issue 22) pp:18711-18717
Publication Date(Web):03 Feb 2016
DOI:10.1039/C5RA24392K
Anion to nerve agent simulant detection by relay recognition has been designed and realized for the first time with sequence specificity (F− → DCNP) via a fluorescence “off–on–on” mechanism. The discrimination of DCNP and DCP via a CIFE (cyclization induced fluorescence enhancement) mechanism has also been demonstrated here. Test strips based on the sensors with F− and DCNP are fabricated, which can act as convenient and efficient nerve agent and F− test kits. The origin of the sequence specificity of different fluorescence recognition was revealed through single X-ray crystal and NMR analysis.
Co-reporter:Krishnendu Aich, Sangita Das, Shyamaprosad Goswami, Ching Kheng Quah, Deblina Sarkar, Tapan Kumar Mondal and Hoong-Kun Fun
New Journal of Chemistry 2016 vol. 40(Issue 8) pp:6907-6915
Publication Date(Web):03 Jun 2016
DOI:10.1039/C6NJ00063K
Three carbazole based benzimidazole derivatives exhibiting the effect of intramolecular charge transfer (ICT) caused by the donor–acceptor interaction between their carbazole and benzimidazole units were synthesized. Their photophysical properties were systematically investigated in various solvents with different polarities. Positive solvatofluorochromic effects were observed with the change of solvent from non-polar to polar for all of the three dyes. The synthesized compounds presented proton-induced absorption as well as ratiometric emission changes, indicating that these compounds might be used as proton sensors. The dyes in their solid state are also able to detect acid vapours. The optimized structures of the dyes and their protonated forms were calculated by density functional theory calculations.
Co-reporter:Sangita Das, Krishnendu Aich, Shyamaprosad Goswami, Ching Kheng Quah and Hoong-Kun Fun
New Journal of Chemistry 2016 vol. 40(Issue 7) pp:6414-6420
Publication Date(Web):16 May 2016
DOI:10.1039/C5NJ03598H
A benzothiazole conjugated quinoline derivative appended with rhodamine-6G acts as an efficient FRET-based single molecular switch for Fe3+. The structure of the probe was confirmed through its single crystal X-ray study. The sensor demonstrates an immediate fluorescence ratiometric response specific towards Fe3+ which also allows facile naked-eye detection of Fe3+. The probe is highly selective only towards Fe3+ in comparison to other environmentally important cations, including Fe2+. Moreover, the detection limit was found to be in the 10−8 M range for the recognition of Fe3+.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Urmila Saha, Sibaprasad Maity, Kalyani Khanra and Nandan Bhattacharyya
Organic & Biomolecular Chemistry 2015 vol. 13(Issue 7) pp:2134-2139
Publication Date(Web):05 Dec 2014
DOI:10.1039/C4OB01842G
Our designed and synthesized chemosensor naphthalene based chromenyl derivative (NAC) [1-(3-hydroxy-3 methyl-3H-benzo[f]chromen-2-yl) ethanone] has been used for fast (<30 s, DL = 0.22 ppb) and selective detection of N2H4 by a new way via the chromenyl ring opening followed by the pyrazole ring formation giving a strong blue fluorescence. The DFT study and the real application in different water samples along with the dipstick method in low cost devices have also been performed here. Human lung cancer cells (NCI-H460) have been used for hydrazinolysis of the NAC in vivo system for detection by the appearance of blue fluorescence and also for the MTT assay showing its remarkable cancer sensitivity.
Co-reporter:Shyamaprosad Goswami, Krishnendu Aich, Sangita Das, Chitrangada Das Mukhopadhyay, Deblina Sarkar and Tapan Kumar Mondal
Dalton Transactions 2015 vol. 44(Issue 12) pp:5763-5770
Publication Date(Web):10 Feb 2015
DOI:10.1039/C4DT02463J
A new quinoline based sensor was developed and applied for the selective detection of Cd2+ both in vitro and in vivo. The designed probe displays a straightforward approach for the selective detection of Cd2+ with a prominent fluorescence enhancement along with a large red shift (∼38 nm), which may be because of the CHEF (chelation-enhanced fluorescence) and ICT (internal charge transfer) processes after interaction with Cd2+. The interference from other biologically important competing metal ions, particularly Zn2+, has not been observed. The visible-light excitability of the probe merits in the viewpoint of its biological application. The probe enables the detection of intracellular Cd2+ with non-cytotoxic effects, which was demonstrated with the live RAW cells. The experimentally observed change in the structure and electronic properties of the sensor after the addition of Cd2+ were modelled by the density functional theory (DFT) and time-dependent density functional theory (TDDFT) computational calculations, respectively. Moreover, the test strip experiment with this sensor exhibits both absorption and fluorescence color changes when exposed to Cd2+ in a mixed aqueous solution, which also makes the probe more useful. The minimum limit of detection of Cd2+ by the probe was in the range of 9.9 × 10−8 M level.
Co-reporter:Sima Paul, Abhishek Manna and Shyamaprosad Goswami
Dalton Transactions 2015 vol. 44(Issue 26) pp:11805-11810
Publication Date(Web):19 May 2015
DOI:10.1039/C5DT01314C
A chemosensor was developed which could selectively detect and differentiate trivalent metal ions (Al3+, Cr3+ and Fe3+) upon single excitation at two different wavelengths in aqueous medium. This probe selectively detects trivalent ions in the presence of different metal ions in aqueous medium. It shows an excellent performance in the “dipstick” method.
Co-reporter:Sima Paul, Shyamaprosad Goswami and Chitrangada Das Mukhopadhyay
New Journal of Chemistry 2015 vol. 39(Issue 11) pp:8940-8947
Publication Date(Web):11 Sep 2015
DOI:10.1039/C5NJ01297J
A ratiometric fluorescent and colorimetric probe for hydrogen sulfide has been developed by combining benzothiazole and the cyanine moiety. Due to its fast response and a large Stokes shift, it was used for sensitive and selective detection of hydrogen sulfide. Moreover, this probe detects SH− both in solid and vapor phases. Its potential for biological applications was confirmed by employing it for fluorescence imaging of SH− in living cells.
Co-reporter:Sangita Das, Shyamaprosad Goswami, Krishnendu Aich, Kakali Ghoshal, Ching Kheng Quah, Maitree Bhattacharyya and Hoong-Kun Fun
New Journal of Chemistry 2015 vol. 39(Issue 11) pp:8582-8587
Publication Date(Web):20 Aug 2015
DOI:10.1039/C5NJ01468A
Based on excited state intramolecular proton transfer (ESIPT) and chelation enhanced fluorescence (CHEF) mechanisms, a new fluorescence ratiometric probe for Al3+ was designed and synthesized, and its structure was confirmed through single crystal X-ray study. This probe is capable of showing excited state intramolecular proton transfer through two different pathways. The introduction of Al3+ in a mixed aqueous solution with the probe results in an abrupt change in the photophysical properties of the probe. A ratiometric emission profile was observed in the presence of Al3+. Interestingly, the presence of other metal ions (especially trivalent ions, e.g. Fe3+, Cr3+, Ga3+ and In3+) do not perturb the fluorescence intensity of the probe (except Cu2+ and Pb2+, where slight changes were noticed). This indicates that the probe shows high affinity towards Al3+. The ratiometric sensing phenomenon may be explained by the presence of two different mechanisms, namely, excited state intramolecular proton transfer and chelation induced enhanced fluorescence, which are demonstrated by the probe in presence of Al3+ in the excited state. The complexation of the probe with Al3+ inhibits excited state intramolecular proton transfer while the chelation induced enhanced fluorescence mechanism becomes dominant. The probe efficiently detected the cellular uptake of Al3+, which is demonstrated here with human blood-cell imaging. Moreover, the detection limit was found to be 6.72 × 10−8 M.
Co-reporter:Avijit Kumar Das, Shyamaprosad Goswami, Ching Kheng Quah and Hoong-Kun Fun
New Journal of Chemistry 2015 vol. 39(Issue 7) pp:5669-5675
Publication Date(Web):12 May 2015
DOI:10.1039/C5NJ00689A
The “Addition–NGP (neighbouring group participation)–Elimination” technique has been used for the ratiometric sensing of H2S/HS−. We report herein the sensing of H2S by the nucleophilic addition of H2S/HS− to a –CHO group of R1 adjacent to naphthyl hydroxyl followed by NGP of thiol through a probable six-membered transition state that undergoes the cleavage of the dinitrophenyl ether moiety. In contrast, R2 undergoes a probable addition and elimination mechanism forming a Meisenheimer complex, which also cleaves the ether moiety. However, herein, the reaction is very slow compared to R1, which works through NGP. The probe can be highly promising for selectivity and sensitivity, to detect H2S/HS− with rapid response (<3 min) and it opens a new way for the thiolysis of the ortho-hydroxy aldehyde platform by cleavage of an active ether linkage. Test strips based on R1 were fabricated, which could act as a convenient and efficient H2S/HS− test kit to detect H2S/HS− in an aqueous solution and in a solid phase for practical application.
Co-reporter:Abhishek Manna and Shyamaprosad Goswami
New Journal of Chemistry 2015 vol. 39(Issue 6) pp:4424-4429
Publication Date(Web):25 Mar 2015
DOI:10.1039/C5NJ00307E
We have designed an ESIPT-based ratiometric sensor (3-(benzo[d]thiazol-2-yl)-2-hydroxybenzylidene)thiosemicarbazide (BTHT) for detecting OCl− with high selectivity and sensitivity and a “naked-eye” colour change (from orange to blue under UV light). Here, strong H-bonding-mediated inhibition of 2-way excited-state intramolecular proton transfer (ESIPT) in BTHT is observed over other anions and oxidants in aqueous solution. The sensor is remarkably efficient for the sensitive recognition of hypochlorites present in differentially treated tap water.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
New Journal of Chemistry 2015 vol. 39(Issue 3) pp:2300-2305
Publication Date(Web):16 Jan 2015
DOI:10.1039/C4NJ02220C
A new ‘‘naked-eye’’ ratiometric colorimetric and fluorometric chemodosimeter (PBF) was constructed to enable trace vapor detection of hydrazine. This probe utilizes an irreversible and fast hydrazine-promoted cleavage of the ester linkage in PBF. This probe was shown to be highly selective for hydrazine, and showed real time response as well as a positive linear relationship to hydrazine concentration. The probe also shows an excellent performance in the ‘‘dip stick’’ method.
Co-reporter:Shyamaprosad Goswami, Sibaprasad Maity, Annada C. Maity, Avijit kumar Das, Bholanath Pakhira, Kalyani Khanra, Nandan Bhattacharyya and Sabyasachi Sarkar
RSC Advances 2015 vol. 5(Issue 8) pp:5735-5740
Publication Date(Web):08 Dec 2014
DOI:10.1039/C4RA07838A
An excited state intramolecular proton transfer (ESIPT) enabled fluorescent sensor phenanthroline diimino phenol (PDP) for Hg2+ has been designed and synthesized. PDP acts as a dual sensor and selectively detects only Hg2+ in mixed aqueous medium and fluoride in acetonitrile medium over other competing metal ions and anions. The binding of PDP with Hg2+ is supported by DFT. The ESIPT phenomenon in PDP is favored in the presence of Hg2+, which is rarely reported, along with an intense red fluorescence suppressing other competing metal ions. Among different anionic analytes, only fluoride shows a visually detectable exciting color change from pale yellow to pink with almost similar emission characteristics. PDP also demonstrates its importance in the fluorescent imaging of Hg2+ ions in human cancer cells.
Co-reporter:Shyamaprosad Goswami, Sangita Das and Krishnendu Aich
RSC Advances 2015 vol. 5(Issue 37) pp:28996-29001
Publication Date(Web):09 Mar 2015
DOI:10.1039/C5RA01216C
A new chromogenic as well as fluorogenic protocol based on the spirobenzopyran system for the selective detection of nerve agent mimics (diethyl chlorophosphate or DCP vapour) within a few seconds (∼30 s) is designed, synthesized and characterized in this study. The nucleophilic attack from the oxygen atom of the spiro ring on the electrophilic phosphonyl group of DCP (diethyl chlorophosphate) causes the opening of the spiro (SP) framework and ultimately gives rise to the meta stable merocyanine (MC) form to give a fluorescent species, which gives a signal in the red region (∼675 nm). The ‘turn-on’ red fluorescence and a colorimetric change from colourless to yellow was observed upon the addition of DCP, which evokes almost 124 and 84 fold enhancement in the absorbance and emission intensity, respectively, compare to the probe itself. To the best of our knowledge, such a DCP sensor based on the spirobenzopyran network has not been reported to date. Moreover, the detection limit of this probe was found to be in 10−8 M level in the solution phase. We also developed it as a portable chemosensor kit for DCP and demonstrated its practical application in real-time monitoring.
Co-reporter:Krishnendu Aich, Shyamaprosad Goswami, Sangita Das and Chitrangada Das Mukhopadhyay
RSC Advances 2015 vol. 5(Issue 39) pp:31189-31194
Publication Date(Web):25 Mar 2015
DOI:10.1039/C5RA03353E
A new chelator and ICT donor based visible light excitable Zn2+ sensor was designed and developed by integrating quinoline and 2-hydroxy-3-(hydroxymethyl)-5-methylbenzaldehyde. The probe is sensitive towards Zn2+ in absorbance as well as in fluorescence experiments in 90% aqueous medium. The sensor demonstrates Zn2+-specific emission enhancement due to the ICT and CHEF process with the LOD in the range of 10−8 M. The fluorescence quantum yield of the chemosensor is only 0.02, and it increases almost 11-fold (0.22) after complexation with Zn2+. Interestingly, the introduction of other metal ions causes the fluorescence intensity to remain almost unchanged. Moreover, the ability of the probe (BQ) to sense Zn2+ in living cells has been explored.
Co-reporter: Shyamaprosad Goswami;Krishnendu Aich;Sangita Das;Bholanath Pakhira;Kakali Ghoshal;Dr. Ching Kheng Quah;Dr. Maitree Bhattacharyya; Hoong-Kun Fun; Sabyasachi Sarkar
Chemistry – An Asian Journal 2015 Volume 10( Issue 3) pp:694-700
Publication Date(Web):
DOI:10.1002/asia.201403234
Abstract
A new visible-light-excitable fluorescence ratiometric probe for OCl− has been developed based on a triphenylamine-diamiomaleonitrile (TAM) moiety. The structure of the dye was confirmed by single-crystal X-ray analysis. It behaves as a highly selective and sensitive probe for OCl− over other analytes with a fast response time (∼100 s). OCl− reacts with the probe leading to the formation of the corresponding aldehyde in a mixed-aqueous system. The detection limit of the probe is in the 10−8 M range. The probe (TAM) also exhibits solvatofluorochromism. Changing the solvent from non-polar to polar, the emission band of TAM largely red-shifted. Moreover, the probe shows an excellent performance in real-life application in detecting OCl− in human blood cells. The experimentally observed changes in the structure and electronic properties of the probe after reaction with OCl− were studied by DFT and TDDFT computational calculations.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Abhishek Manna, Anup Kumar Maity, Partha Saha, Ching Kheng Quah, Hoong-Kun Fun, and Hatem A. Abdel-Aziz
Analytical Chemistry 2014 Volume 86(Issue 13) pp:6315
Publication Date(Web):May 8, 2014
DOI:10.1021/ac500418k
By employing the oxidation property of hypochlorite (OCl–), a novel rhodamine-based hydrazide of the chiral acid ((S)-(−)-2-pyrrolidone-5-carboxylic acid) (RHHP) was designed and synthesized for detection of OCl– absolutely in aqueous medium at nanomolar level. The structure of the chiral sensor was also proved by the X-ray crystallography. The bioactivity and the application of the probe for detection of OCl– in natural water system have been demonstrated. A plausible mechanism for oxidation of the sensor followed by hydrolysis is also proposed. The sensibility of the receptor toward OCl– was studied in absolute aqueous media, and the detection limit of hypochlorite-mediated oxidation to the receptor in nanomolar level makes this platform (RHHP) an ultrasensitive and unique system for OCl– oxidation.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Bholanath Pakhira, Sohini Basu Roy, Anup Kumar Maity, Partha Saha and Sabyasachi Sarkar
Dalton Transactions 2014 vol. 43(Issue 33) pp:12689-12697
Publication Date(Web):23 Jun 2014
DOI:10.1039/C4DT01262C
A new zinc(II) complex with a condensed hydroxynaphthyl pyridine (SPHN) as the coordinated ligand has been synthesized for the selective recognition of pyrophosphate (PPi) over other anions including phosphate in a mixed aqueous solution. The fluorescence enhancement of SPHN in association with Zn2+ ions is quenched in the presence of intracellular pyrophosphate. This phenomenon is utilized in the construction of a logic gate. The binding of SPHN with Zn2+ and its displacement by PPi have been established by photophysical investigation and supported by the DFT level of studies. The development of blue fluorescence in the {SPNH–Zn} complex upon binding of zinc with SPHN is shown to be useful as a nucleus marker in a cell similar to the commercially available staining compound, DAPI (diamino-2-phenylindole).
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Anup Kumar Maity, Abhishek Manna, Krishnendu Aich, Sibaprasad Maity, Partha Saha and Tarun Kanti Mandal
Dalton Transactions 2014 vol. 43(Issue 1) pp:231-239
Publication Date(Web):16 Sep 2013
DOI:10.1039/C3DT51851E
A new spirobenzopyran derivative (SPNH) was designed and synthesized which was applied in simultaneous colorimetric and NIR fluorescence detections for Cr3+. This spirobenzopyran receptor is normally colorless in aqueous organic media but the formation of merocyanine occurs by Cr3+ showing a yellow color. Here the formation of yellow color in UV-vis spectra and strong NIR fluorescence emission at 675 nm makes SPNH a good sensor for Cr3+ ion. It is also found to be useful in cell imaging and in construction of logic gate. It shows INHIBIT gate in fluorescence and OR gate in absorption. To the best of our knowledge, this is the first report of NIR fluorescence emission of a spirobenzopyran derivative by Cr3+ and its application to cell-biology and also in the logic gate.
Co-reporter:Shyamaprosad Goswami, Shampa Chakraborty, Sima Paul, Sandipan Halder, Sukanya Panja and Subhra Kanti Mukhopadhyay
Organic & Biomolecular Chemistry 2014 vol. 12(Issue 19) pp:3037-3044
Publication Date(Web):21 Feb 2014
DOI:10.1039/C4OB00067F
A new pyrene based fluorescence probe has been synthesized for fluorogenic detection of Cu2+ in acetonitrile–aqueous media (7:3 CH3CN–HEPES buffer, v/v, at pH 7.5) with bioimaging in both prokaryotic (Candida albicans cells) and eukaryotic (Tecoma stans pollen cells) living cells. The anion recognition properties of the sensor have also been studied in acetonitrile by fluorescence methods which show remarkable sensitivity toward fluoride over other anions examined.
Co-reporter:Shyamaprosad Goswami, Shampa Chakraborty, Monoj Kumar Adak, Sandipan Halder, Ching Kheng Quah, Hoong-Kun Fun, Bholanath Pakhira and Sabyasachi Sarkar
New Journal of Chemistry 2014 vol. 38(Issue 12) pp:6230-6235
Publication Date(Web):08 Oct 2014
DOI:10.1039/C4NJ01498G
The monohydrazone of quinoxaline aldehyde (HOQA) is found to be a ratiometric and colorimetric probe for Ni2+. HOQA shows a remarkable color change from colorless to yellow upon specific and selective binding to nickel that can be identified even by the naked eye. The cation recognition property of the receptor is monitored by UV-vis and 1H-NMR titrations and also by DFT (Density Functional Theory) and TD-DFT (Time Dependent Density Functional Theory) calculations.
Co-reporter:Shyamaprosad Goswami, Krishnendu Aich, Sangita Das, Sohini Basu Roy, Bholanath Pakhira and Sabyasachi Sarkar
RSC Advances 2014 vol. 4(Issue 27) pp:14210-14214
Publication Date(Web):04 Feb 2014
DOI:10.1039/C3RA46663A
A fluorescein based reactive probe has been designed and synthesized to detect hydrazine selectively over other common analytes. We used here 4-bromobutyrate as a masking unit of fluorescein dye. Hydrazine plays here the role of a de-masking agent to set free the fluorescein dye through a simultaneous substitution–cyclisation–elimination process. This leads to ‘turn on’ fluorescence with easily discernible color change with a fast response time (<15 minutes).
Co-reporter:Shyamaprosad Goswami, Sibaprasad Maity, Annada C. Maity, Anup Kumar Maity, Avijit Kumar Das and Partha Saha
RSC Advances 2014 vol. 4(Issue 12) pp:6300-6305
Publication Date(Web):19 Nov 2013
DOI:10.1039/C3RA46280C
On the basis of fluorescence resonance energy transfer (FRET) from benzimidazole to a rhodamine moiety, a rhodamine–benzimidazole conjugate (RBC) ratiometric fluorescent probe has been designed and synthesized. The RBC selectively binds to Cu2+, showing visually observable changes in absorption and emission behavior, and demonstrates an effective intracellular Cu2+ imaging ability, allowing it to function as a cytoplasm marker.
Co-reporter:Swapan Dey, Dibyendu Sain and Shyamaprosad Goswami
RSC Advances 2014 vol. 4(Issue 1) pp:428-433
Publication Date(Web):21 Nov 2013
DOI:10.1039/C3RA45197F
Naphthyridine based fluorogenic receptors (R1, R2, R3 and R4) have been synthesised for the recognition of uric acid (UA). The receptors are very useful for potential applications arising from complexation reactions as demonstrated by 1H NMR, UV-vis and fluorescence studies. The association constants (Ka) between the receptors and UA have been reported using UV and fluorescence techniques. The minimisation energy calculations and molecular modelling studies for the host–guest assemblies have been discussed in this context.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Monalisa Mondal and Debasish Sarkar
RSC Advances 2014 vol. 4(Issue 107) pp:62639-62643
Publication Date(Web):05 Nov 2014
DOI:10.1039/C4RA12537A
For the rapid, ratiometric, fluorogenic and “naked eye” detection of H2S/S2−, a pro-excited state intramolecular proton transfer (ESIPT)-based receptor, 2-formyl-benzoic acid 2-benzothiazol-2-yl-phenyl ester (FBBP) has been designed. In the presence of H2S/S2− in preference to other common species, 2-(2-hydroxyphenyl)benzothiazole, a well known ESIPT-containing agent, is recovered from FBBP. Thus, H2S/S2− can be detected in vitro and in vivo by such a simple, easy-to-synthesise, practical ratiometric sensor.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
RSC Advances 2014 vol. 4(Issue 82) pp:43778-43784
Publication Date(Web):05 Sep 2014
DOI:10.1039/C4RA07396G
The metal catalyzed oxidation reaction in a simple rhodamine–carbazole dyad (a carbazole nucleus flanked by two rhodamine moieties) was carried out in the presence of CAN. This sensor displays a very fast response (<1 min) toward CAN at room temperature with a ‘naked-eye’ change. This TBET based sensor is also highly selective and sensitive towards CAN. The chemosensor showed excellent performance in the “dip-stick” method.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Anup Kumar Maity, Partha Saha, Ching Kheng Quah and Hoong-Kun Fun
RSC Advances 2014 vol. 4(Issue 65) pp:34572-34576
Publication Date(Web):24 Jul 2014
DOI:10.1039/C4RA05714G
Our designed chemosensor, rhodamine-HBT-dyad (RHD), selectively detects two biologically important ions (Al3+ and Zn2+) at two different wavelengths (‘naked-eye’ colors red and green, respectively) through two different mechanisms (i.e. FRET and ESIPT) at ppm level. The sensor can also detect the Al3+ ion through displacement of the Zn2+ ion in vivo.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Prasanta Kumar Nandi, Kakali Ghoshal, Ching Kheng Quah, Maitree Bhattacharyya, Hoong-Kun Fun and Hatem A. Abdel-Aziz
RSC Advances 2014 vol. 4(Issue 47) pp:24881-24886
Publication Date(Web):23 May 2014
DOI:10.1039/C4RA03200D
A rhodamine–quinoline based chemodosimeter (RHQ) has been designed, synthesized and characterized in this paper. The structure of the sensor is confirmed through single crystal X-ray study. It detects hypochlorite (OCl−) selectively among other analytes studied. It showed colorimetric and orange-red fluorescence “turn-on” upon addition of OCl−. The OCl−-promoted ring opening of the rhodamine spirolactam ring in RHQ evokes a large absorbance as well as fluorescence enhancement in water–acetonitrile (1/1, v/v) medium with no significant response to other competitive analytes. Furthermore, we demonstrate here that RHQ can endogenously detect OCl− in human blood cells (peripheral blood mononuclear cells). It also exhibits excellent performance in the “dip stick” method. The optimized structure of the probe is calculated by density functional theory calculations. Moreover, the limit of detection of the probe is in the 10−8 M range.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna and Sima Paul
RSC Advances 2014 vol. 4(Issue 42) pp:21984-21988
Publication Date(Web):23 Apr 2014
DOI:10.1039/C4RA01060D
A rhodamine-based new chemosensor, RHM, has been designed and synthesized. It reacts selectively with the organophosphate compound, DCP, a well-known nerve gas simulant (both in the liquid and vapour phase). Moreover, RHM offers the potential for detection by the naked eye for color and fluorescence change. The sensing phenomenon is supported by DFT calculation.
Co-reporter:Shyamaprosad Goswami, Shampa Chakraborty, Avijit Kumar Das, Abhishek Manna, Aditya Bhattacharyya, Ching Kheng Quah and Hoong-Kun Fun
RSC Advances 2014 vol. 4(Issue 40) pp:20922-20926
Publication Date(Web):20 Mar 2014
DOI:10.1039/C4RA00594E
A quinoxaline based colorimetric nickel sensor, HQAP [2-(quinoxalin-2-ylmethyleneamine)phenol] with high selectivity and sensitivity toward Ni2+ ions is shown to have potential for practical use. The absorption maximum of HQAP shows a large ratiometric shift from 306 to 570 nm (ΔI = 264 nm) in the presence of Ni2+ ions, and the color changes from colorless to deep violet only upon addition of Ni2+ which is very easily observed by the naked eye (the detection limit of Ni2+ is as low as 4.16 μM in solution). The predicted binding mode (2:1) from spectral analysis and Job's plot was confirmed by the single crystal X-ray structure of the complex.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Abhishek Manna, Anup Kumar Maity, Hoong-Kun Fun, Ching Kheng Quah, Partha Saha
Tetrahedron Letters 2014 Volume 55(Issue 16) pp:2633-2638
Publication Date(Web):16 April 2014
DOI:10.1016/j.tetlet.2014.03.003
A ratiometric fluorescent turn-on probe for fluoride ion, based on modulation of the excited-state intramolecular proton transfer (ESIPT) process by chemodosimetric desilylation pathway is reported. The probe SNBT (silyl protected hydroxynaphthalene benzothiazole moiety) shows a significant increase of ratiometric absorption band at 440 nm and emission band at 477 nm by the deprotection of fluoride mediated silyl bond cleavage in CH3CN–H2O (8/2, v/v, 25 °C). The test strips based on SNBT and F− are fabricated, which can act as a convenient and efficient F− test kits. Furthermore, the biological application shows that it can be very useful as a selective fluoride probe in the fluorescence imaging of living cells.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Deblina Sarkar, Tapan Kumar Mondal
Tetrahedron Letters 2014 Volume 55(Issue 16) pp:2695-2699
Publication Date(Web):16 April 2014
DOI:10.1016/j.tetlet.2014.03.041
A coumarin-based sensor containing trifluoroacetyl acetonate moiety was designed, synthesized, and applied for hydrazine detection. Hydrazinolysis of the chemodosimeter results in a prominent chromogenic and fluorescence ratiometric response toward hydrazine within 3 min. The probe is highly selective toward hydrazine over other important amines and other biologically and environmentally abundant analytes. The limit of detection (LOD) of the probe is in 10−6 M range. The sensing mechanism was supported by NMR and HRMS analysis. The experimentally observed change in structure and electronic properties of the sensor after reaction with hydrazine was modeled by Density Functional Theory (DFT) and Time Dependent Density Functional Theory (TDDFT) computational calculations, respectively.
Co-reporter:Shyamaprosad Goswami, Manas Kumar Das, Abhishek Manna
Tetrahedron Letters 2014 Volume 55(Issue 16) pp:2707-2710
Publication Date(Web):16 April 2014
DOI:10.1016/j.tetlet.2014.03.068
The design and synthesis of a new pterin-based ratiometric and sensitive ‘naked-eye’ sensor R for highly selective recognition of acetate are reported. The acidic lactam NH and the NH of 2-N-pivaloyl group of receptor R along with 2,4-dinitrophenyl hydrazone group having the other acidic NH moiety lead to the binding of acetate anion in a 1:2 ratio by change of spectroscopic behavior on complexation (UV–vis and 1H NMR studies) which is also proven by Job plot. The sharp color change from light yellow to violet promises R to be a useful chromogenic ratiometric sensor for acetate amongst other common anions.
Co-reporter:Shyamaprosad Goswami, Sima Paul, Abhishek Manna
Tetrahedron Letters 2014 Volume 55(Issue 29) pp:3946-3949
Publication Date(Web):16 July 2014
DOI:10.1016/j.tetlet.2014.05.018
We have developed a FRET-based ratiometric fluorescent probe for the detection of CN− using a fluorescein–Zn–naphthalene ensemble (NFH·Zn2+). The sensing mechanism was ascribed by displacement approach. The chemosensor exhibits high selectivity and sensibility for CN−. The speculation was supported by fluorescence emission spectra, UV–vis spectrum, 1H NMR titration experiments, and mass spectra. The interconversion of probe NFH and NFH·Zn2+ via the complexation/decomplexation by the modulation of Zn2+/CN− mimics INHIBIT gate. In addition, it also shows an excellent performance in ‘dip stick’ method.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Avijit K. Das, Prasanta K. Nandi, Anup Kumar Maity, Partha Saha
Tetrahedron Letters 2014 Volume 55(Issue 2) pp:490-494
Publication Date(Web):8 January 2014
DOI:10.1016/j.tetlet.2013.11.055
5(Benzothiazol-2-yl)-4-hydroxyisophthalaldehyde (BHI), an intense ESIPT containing molecule in mixed media loses its properties due to resonance-assisted H-bond (RAHB) in absolute water. Due to resonance-assisted H-bond the o-aldehyde is more reactive than the other one. With addition of cysteine/homocysteine into this solution the o-aldehyde group gets transformed into thiazolidine/thiazine ring, respectively, and the phenolic proton becomes free enough for transfer to nitrogen of the benzothiazole ring in excited state, that is, the ESIPT of BHI is turned on. Thus we can detect cysteine/homocysteine in water as well as in live cells.
Co-reporter:Shyamaprosad Goswami, Sibaprasad Maity, Annada C. Maity, Avijit Kumar Das, Kalyani Khanra, Tarun Kanti Mandal, Nandan Bhattacharyya
Tetrahedron Letters 2014 Volume 55(Issue 43) pp:5993-5997
Publication Date(Web):22 October 2014
DOI:10.1016/j.tetlet.2014.09.014
A new macrocyclic fluorescent chemosensor piperazine coupled diimine phenol (PCDP) which forms extremely selective Zn(II) complex and thus builds up the platform for H2PO4− (DHP) sensing in mixed aqueous medium, has been designed and synthesized. The binding of PCDP with Zn2+ and its displacement by DHP have been supported by DFT studies. The blue fluorescence in the PCDP–Zn complex is useful for bio-imaging. The fluorescence enhancement of PCDP on association with Zn2+ ion is quenched sharply in the presence of intracellular DHP.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Bholanath Pakhira, Sukanya Panja, Subhra Kanti Mukherjee, and Sabyasachi Sarkar
Organic Letters 2013 Volume 15(Issue 21) pp:5412-5415
Publication Date(Web):October 18, 2013
DOI:10.1021/ol4026759
A probe based on 2-(2′-hydroxyphenyl) benzothiazole (HBT) has been synthesized and used for the ratiometric detection of hydrazine. The probe is designed in such a way that the excited state intramolecular proton transfer (ESIPT) of the HBT moiety gets blocked. The chemodosimetric approach of hydrazine to the probe results in the recovery of the ESIPT by removal of a free HBT moiety through subsequent substitution, cyclization, and elimination processes. The probe is successfully demonstrated to enable the detection of hydrazine in live cells.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Ching Kheng Quah and Hoong-Kun Fun
Chemical Communications 2013 vol. 49(Issue 99) pp:11656-11658
Publication Date(Web):18 Oct 2013
DOI:10.1039/C3CC47121G
We have designed a chemodosimeter DPNO (weak fluorescence) which can be oxidized to HPNO (strong blue fluorescence) by OCl− with high selectivity and sensitivity in a ratiometric approach with a noticeably lower detection limit. The sensor could be useful for the detection of hypochlorites in tap water.
Co-reporter:Shymaprosad Goswami, Krishnendu Aich, Sangita Das, Avijit Kumar Das, Deblina Sarkar, Sukanya Panja, Tapan Kumar Mondal and Subhrakanti Mukhopadhyay
Chemical Communications 2013 vol. 49(Issue 91) pp:10739-10741
Publication Date(Web):27 Sep 2013
DOI:10.1039/C3CC46860G
A spirobenzopyran-quinoline (SBPQ) based sensor was synthesized which selectively detects trivalent ions viz. Al3+, Fe3+ and Cr3+ through a fluorescence turn on signal in the red region (∼675 nm) with the detection limit in the order of 10−8 M. The potentiality of the probe was confirmed by employing it for fluorescence bio-imaging with Al3+ in three different types of live-cells.
Co-reporter:Shymaprosad Goswami, Abhishek Manna, Sima Paul, Avijit K. Das, Krishnendu Aich and Prasanta K. Nandi
Chemical Communications 2013 vol. 49(Issue 28) pp:2912-2914
Publication Date(Web):21 Feb 2013
DOI:10.1039/C3CC39256B
For ratiometric “naked eye” detection of CN−, an ESIPT exhibiting benzothiazole receptor (BHI) is designed having one aldehyde group ortho and the other aldehyde para to the OH group respectively. Due to RAHBs, the ortho aldehyde group is highly reactive undergoing nucleophilic cyanide addition selectively, which hampered ESIPT. This is also supported by DFT and TD-DFT calculations.
Co-reporter:Shyamaprosad Goswami, Krishnendu Aich, Sangita Das, Avijit Kumar Das, Abhishek Manna and Sandipan Halder
Analyst 2013 vol. 138(Issue 6) pp:1903-1907
Publication Date(Web):11 Jan 2013
DOI:10.1039/C3AN36884J
A new rhodamine–quinoline based dyad has been synthesized. It shows a highly selective response to Cd2+ in the presence of other competing metal ions in aqueous media (pH = 7.1). The detection limit of the sensor is in the 10−7 M level.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Krishnendu Aich, Abhishek Manna, Sibaprasad Maity, Kalyani Khanra and Nandan Bhattacharyya
Analyst 2013 vol. 138(Issue 16) pp:4593-4598
Publication Date(Web):11 Jun 2013
DOI:10.1039/C3AN00067B
A new “naked-eye” and ratiometric fluorescent zinc sensor (TAQ) of carboxamidoquinoline with 2-chloro-N-(quinol-8-yl)-acetamide as a receptor was designed and synthesized. The sensor TAQ shows good water solubility and high selectivity for sensing; about a 15-fold increase in fluorescence quantum yield and a 100 nm red-shift of fluorescence emission upon binding Zn2+ in aqueous HEPES buffer solution are observed. The human lung cancer cell line (A549) activity is also demonstrated.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
Dalton Transactions 2013 vol. 42(Issue 30) pp:10682-10686
Publication Date(Web):10 Jun 2013
DOI:10.1039/C3DT51262B
A hybrid carbazole hemicyanine dye (receptor CHD) was developed as a new visible and near infrared chemodosimeter type sensor with high ratiometric selectivity towards cyanide in the presence of other anions in aqueous solution. The chemosensor also showed excellent performance when used in the “dip stick” method, i.e. in solid phase (TLC plates).
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Anup Kumar Maity, Sima Paul, Avijit Kumar Das, Manas Kumar Das, Partha Saha, Ching Kheng Quah and Hoong-Kun Fun
Dalton Transactions 2013 vol. 42(Issue 36) pp:12844-12848
Publication Date(Web):12 Jul 2013
DOI:10.1039/C3DT51591E
A new rhodamine based chemosensor, cyano-rhodamine, has been designed and synthesized with a green approach which shows a specific ‘C–CN’ bond breaking with the action of the Pd2+ ion to produce the specific color and fluorescence of rhodamine 6G itself in solution and in HeLa cells.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Deblina Sarkar, Tapan Kumar Mondal, Ching Kheng Quah and Hoong-Kun Fun
Dalton Transactions 2013 vol. 42(Issue 42) pp:15113-15119
Publication Date(Web):13 Aug 2013
DOI:10.1039/C3DT51974K
A new fluorescent probe was synthesized from rhodamine-6G and 6-(hydroxymethyl) picolinohydrazide for the sensing of Fe3+ in an aqueous environment. The structure of the sensor was confirmed through its single crystal X-ray study. It exhibits a high specificity and sensitivity towards Fe3+ over other interfering heavy and transition metal ions (HTM). The turn-on greenish-yellow fluorescence and a colorimetric change from colourless to pink were observed upon addition of Fe3+ which evokes almost 116- and 23-fold enhancement in absorbance and emission intensity respectively in an acetonitrile–water (1:1, v/v, 25 °C) solution at a neutral pH (pH = 7.2). The Fe3+ promoted ring opening of the spirolactam framework to the open chain amide platform of the sensor is responsible for its visible colour change and turn-on fluorescence activity. It also exhibits an excellent performance in the “dip stick” method. Moreover the limit of detection of the probe is in the 10−8 M range.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das and Sibaprasad Maity
Dalton Transactions 2013 vol. 42(Issue 46) pp:16259-16263
Publication Date(Web):13 Sep 2013
DOI:10.1039/C3DT52252K
A novel colorimetric and fluorescent chemosensor based on 7-(diethylamino)-3-(pyrimidin-4-yl)-2H-chromen-2-one (PYC) has been designed and synthesized for the detection of Hg2+ in the presence of other competing metals in mixed aqueous media. The PYC exhibits naked eye color change from green to red, and the fluorescence color changes from yellowish green to light orange with Hg2+. It also shows a red shift in wavelength of about 80 nm in absorption spectra. Test strips based on PYC were fabricated, which could act as convenient and efficient Hg2+ test kits.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
Dalton Transactions 2013 vol. 42(Issue 28) pp:10097-10101
Publication Date(Web):16 May 2013
DOI:10.1039/C3DT51238J
The de-diaminomaleonitrile reaction in a simple carbazole diaminomaleonitrile hybrid (CDH) was promoted by OCl− which disrupted the ICT mechanism by breaking the donor and acceptor linkage. This system utilized an irreversible OCl− promoted oxidation reaction and it responded instantaneously at room temperature. The chemosensor also showed excellent performance in tap water and the “dip-stick” method.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Krishnendu Aich, Avijit K. Das and Shampa Chakraborty
Dalton Transactions 2013 vol. 42(Issue 22) pp:8078-8085
Publication Date(Web):12 Mar 2013
DOI:10.1039/C3DT50621E
In this study, we have synthesized a simple Schiff base type isophthaloyl salicylaldehyde hydrazone (ISH) moiety which selectively detects Al(III) and PPi with a fluorescence enhancement at two different wavelengths in aqueous solution. The sensing phenomenon is also reversible and thus the sensor beautifully mimics logic gates (INHIBIT and EXOR gates).
Co-reporter:Shyamaprosad Goswami, Krishnendu Aich, Avijit Kumar Das, Abhishek Manna and Sangita Das
RSC Advances 2013 vol. 3(Issue 7) pp:2412-2416
Publication Date(Web):17 Dec 2012
DOI:10.1039/C2RA22624C
A new naphthalimide–quinoline based probe (NAQ) is designed and synthesized and its structure is confirmed through single crystal analysis. It detects the trivalent ions (Fe3+ or Al3+ or Cr3+) selectively among other alkali and transition metal ions studied. NAQ shows a distinct ratiometric fluorescence behavior upon addition of trivalent metal ions in CH3CN–HEPES buffer solution (40/60, v/v, pH = 7.4). This fluorogenic sensing of NAQ to M3+ (M3+ = Fe3+ or Al3+ or Cr3+) can be observed by the naked eye, when illuminated under the UV light.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
RSC Advances 2013 vol. 3(Issue 47) pp:25079-25085
Publication Date(Web):01 Oct 2013
DOI:10.1039/C3RA44539A
A multifunctional fluorescent chemosensor (PMN) for Al3+ and Zn2+ has been developed, which displays a dual-mode and “off–on” fluorescence response upon addition of Al3+ or Zn2+ at two different wavelengths. This was possibly due to the inhibition of PET and CN isomerism, and the activation of chelation-enhanced fluorescence (CHEF). Moreover, PMN exhibited a preferential second mode of selectivity for Al3+ as it ratiometrically displaces Zn2+ from the [PMN + Zn2+] complex. Such fluorescence modulation behavior mimics the performance of an “OR” logic gate. It also shows an excellent performance in the “dipstick” method.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
RSC Advances 2013 vol. 3(Issue 41) pp:18872-18877
Publication Date(Web):08 Aug 2013
DOI:10.1039/C3RA42771D
Hydrazine is an important industrial chemical but also very toxic. Thus rapid detection of hydrazine is very important. We have judiciously designed and constructed a novel ICT-based ratiometric “naked eye” and fluorescence smart probe, carbazole based malononitrile (CBM), that rapidly (<1 min) and selectively detects hydrazine in the presence of different metal ions, anions and other amines in aqueous medium. As a possible application of the probe, hydrazine sensing in tap water was tested. The probe also shows an excellent performance in the “dip stick” method.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
RSC Advances 2013 vol. 3(Issue 27) pp:10639-10643
Publication Date(Web):10 May 2013
DOI:10.1039/C3RA40984H
A highly selective fluorescence probe, RIH (rhodamine–isatin hybrid) for Al3+ has been designed and synthesized. This new dual signal (colorimetric and fluorogenic “off–on” type) chemosensing ensemble based on the complex between RIH and Al3+ has also been effective to selectively discriminate PPi from other anions in aqueous solution at physiological pH.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich
Tetrahedron Letters 2013 Volume 54(Issue 35) pp:4620-4623
Publication Date(Web):28 August 2013
DOI:10.1016/j.tetlet.2013.06.035
A new internal charge transfer (ICT) based colorimetric as well as fluorogenic sulfur-free probe for highly selective and sensitive monitoring of Hg2+ has been developed and reported in this Letter. It gives a colorimetric and fluorometric response upon addition of Hg2+ in acetonitrile:water (1:1) solution at a physiological pH, with no significant interference of other competitive metal ions. Receptor (TPM) shows a distinct color change from light yellow to orange upon progressive addition of Hg2+, so that it can serve as a naked-eye sensor for Hg2+ ion. It exhibits excellent reproducibility, reversibility, and selectivity with the detection limit at micro-molar level.
Co-reporter:Saikat Kumar Seth, Nirmal Kumar Das, Krishnendu Aich, Debabrata Sen, Hoong-Kun Fun, Shyamaprasad Goswami
Journal of Molecular Structure 2013 Volume 1048() pp:157-165
Publication Date(Web):24 September 2013
DOI:10.1016/j.molstruc.2013.05.048
•Cocrystals having 2D layer architecture.•Cooperativity of strong hydrogen bonding and weak π–π stacking interactions.•Quantification of intermolecular interactions.•Hirshfeld surface and fingerprint plots.Co-crystals of 1a and 1b have been prepared by slow evaporation of the solutions of mixtures of 2,7-dimethyl-1,8-naphthyridine (1), urea (a) and thiourea (b). The structures of the complexes are determined by the single crystal X-ray diffraction and a detailed investigation of the crystal packing and classification of intermolecular interactions is presented by means of Hirshfeld surface analysis which is of considerable current interest in crystal engineering. The X-ray study reveals that the co-crystal formers are envisioned to produce N–H⋯N hydrogen bond as well as N–H⋯O/N–H⋯S pair-wise hydrogen bonds and also the weaker aromatic π⋯π interactions which cooperatively take part in the crystal packing. The recurring feature of the self-assembly in the compounds is the appearance of the molecular ribbon through multiple hydrogen bonding which are further stacked into molecular layers by π⋯π stacking interactions. Hirshfeld surface analysis for visually analyzing intermolecular interactions in crystal structures employing molecular surface contours and 2D Fingerprint plots have been used to examine molecular shapes. Crystal structure analysis supported with the Hirshfeld surface and fingerprint plots enabled the identification of the significant intermolecular interactions.Graphical abstractThe cooperative weak π–π interactions play crucial role in determining the supramolecular layer architecture of naphthyridine co-crystals and the analysis of Hirshfeld surfaces and fingerprint plots facilitate a comparison of intermolecular interactions.
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Deblina Sarkar, Tapan Kumar Mondal
Tetrahedron Letters 2013 Volume 54(Issue 50) pp:6892-6896
Publication Date(Web):11 December 2013
DOI:10.1016/j.tetlet.2013.10.033
In this Letter, we have designed and synthesized two salicylaldehyde based probes (DPSH and ANSH) which selectively detect Zn2+ and HSO4- over other physiologically and environmentally important ions with a fluorescence enhancement at two different wavelengths in aqueous acetonitrile solution. The binding mode and change of electronic properties of DPSH and ANSH with Zn2+ and HSO4- were modeled by DFT (density functional theory) and TDDFT (time dependent density functional theory) computational calculations, respectively. The minimum limits of detection (LOD) of the sensors with both cases were in the order of 10−8 M each.
Co-reporter:Shyamaprosad Goswami, Sibaprasad Maity, Avijit Kumar Das, Annada C. Maity
Tetrahedron Letters 2013 Volume 54(Issue 48) pp:6631-6634
Publication Date(Web):27 November 2013
DOI:10.1016/j.tetlet.2013.09.126
A novel fluorescent probe for the copper(II) ion in mixed aqueous media, based on fluorescence quenching mechanism with noticeable color change from light to dark yellow, was designed and synthesized. It also exhibited high selectivity for acetate in acetonitrile over other common anions in the near infrared region (NIR) accompanied with exciting color changes from light yellow to pink. Hence sensor 1 ascertains its dual chemosensing ability toward Cu(II) and acetate ions as evidenced by competitive experiments.
Co-reporter:Shyamaprosad Goswami, Shampa Chakraborty, Sima Paul, Sandipan Halder, Annada C. Maity
Tetrahedron Letters 2013 Volume 54(Issue 37) pp:5075-5077
Publication Date(Web):11 September 2013
DOI:10.1016/j.tetlet.2013.07.051
A new quinoxaline based receptor (HQNM) has been designed and synthesized which shows a remarkable color change from colorless to yellow on specific binding with nickel. The cation recognition property of the receptor is monitored by the UV–vis and 1H NMR titrations. It is observed that the receptor shows a specific selectivity toward nickel over other interfering cations. Thus, a significant bathochromic shift in UV–vis spectrum with a sharp yellow color in ‘naked-eye’ makes the receptor suitable for the easy detection of nickel ion.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Krishnendu Aich, Avijit Kumar Das, Shampa Chakraborty
Tetrahedron Letters 2013 Volume 54(Issue 14) pp:1785-1789
Publication Date(Web):3 April 2013
DOI:10.1016/j.tetlet.2012.12.092
We have designed and synthesized a triphenyl aminebenzothiazole coupled receptor (TBH) that exhibits a selective, sensitive, colorimetric, and ratiometric rapid response toward cyanide anion in aqueous media. The sensing event is explained by spectroscopy along with DFT calculation and CV diagram. Sensor displays a very fast response (<1 min) toward cyanide at room temperature with a ‘naked-eye’ change over F− and AcO− in aqueous media.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Krishnendu Aich, Abhishek Manna
Tetrahedron Letters 2013 Volume 54(Issue 32) pp:4215-4220
Publication Date(Web):7 August 2013
DOI:10.1016/j.tetlet.2013.05.119
The receptor, naphthalene based benzothiazole (NHBT) shows acetate selectivity in its absorbance and emission behavior among the various interfering anions. Substantially red shifted absorption band and fluorescence emission of NHBT in pure acetonitrile media were developed which drastically got enhanced upon addition of tetrabutylammonium acetate. Excited-state intermolecular proton transfer in the sensor–anion hydrogen-bonding complex was suggested to be the signaling mechanism. NHBT, a good hydrogen-bonding donor, the ESIPT process is inhibited by the formation of a strong acetate-NHBT intermolecular hydrogen bond complex, and the inhibition mechanism consequently results in ratiometric response in absorption and emission spectroscopy, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slide
Co-reporter:Shyamaprosad Goswami, Annada C. Maity, Shampa Chakraborty, Manas Kumar Das, Bhaswati Goswami
Tetrahedron Letters 2013 Volume 54(Issue 19) pp:2373-2376
Publication Date(Web):8 May 2013
DOI:10.1016/j.tetlet.2013.02.090
A new convenient total synthesis of (±) dephospho Form B of molybdenum cofactor has been described. The development of direct thiophene annulation onto pterin from a simple direct thiophene annulation at the alkyne moiety at 6-position of pterin is successfully achieved by using excess of sodium sulfide. This novel method conveniently led to the synthesis of a series of pterin fused α-substituted thiophenes (9–11, respectively).
Co-reporter:Shyamaprosad Goswami, Sibaprasad Maity, Avijit Kumar Das, Annada C. Maity, Tarun Kanti Mandal, Siddhartha Samanta
Tetrahedron Letters 2013 Volume 54(Issue 38) pp:5232-5235
Publication Date(Web):18 September 2013
DOI:10.1016/j.tetlet.2013.07.078
A new dibenzimidazolo diimine sensor (DDS) has been designed and synthesized for selective detection of acetate ion. Significant naked eye recognized color change of DDS solution from light yellow to pink upon addition of only acetate ion is accompanied with near infra red (NIR) emission exploiting excited state intramolecular proton transfer (ESIPT).
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Avijit Kumar Das, Nirmal Kumar Das, Krishnendu Aich, Hoong-Kun Fun, Ching Kheng Quah, Anup Kumar Maity, Partha Saha
Sensors and Actuators B: Chemical 2013 Volume 183() pp:518-525
Publication Date(Web):5 July 2013
DOI:10.1016/j.snb.2013.04.005
A new coumarin containing rhodamine architecture has been synthesized for selective and chromogenic detection of Cu2+ in aqueous media. Cu2+ induced spirocyclic ring opening of the rhodamine dye has been demonstrated by single crystal X-ray structures of the fluorescence probe as well as its bound Cu2+-complex. It is also promising as a Cu2+-selective sensor in the fluorescence imaging of living cells.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Debabrata Sen, Krishnendu Aich, Hoong-Kun Fun, Ching Kheng Quah
Tetrahedron Letters 2012 Volume 53(Issue 36) pp:4819-4823
Publication Date(Web):5 September 2012
DOI:10.1016/j.tetlet.2012.06.104
A new naphthalene based receptor (L) has been designed and synthesized which shows a remarkable color change from colorless to pink on selective binding with acetate. The anion recognition property of the receptor via hydrogen bonding interactions is monitored by UV–vis, fluorescence, and 1H NMR titrations. It is observed that in each case, the receptor shows a specific selectivity toward the acetate ion over other interfering anions. Thus, a significant bathochromic shift in UV–vis spectrum with a sharp pink color in ‘naked-eye’ makes the receptor suitable for the detection of the acetate ion.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Nirmal Kumar Das, Hoong-Kun Fun and Ching Kheng Quah
Chemical Communications 2011 vol. 47(Issue 32) pp:9101-9103
Publication Date(Web):05 Jul 2011
DOI:10.1039/C1CC12845K
A new fluorescence rhodamine derivative bearing an 8-aminoquinoline moiety has been designed and synthesized for selective sensing of Pd2+ in the presence of other competing metal ions in aqueous media. Pd2+ induced spirolactam ring opening of rhodamine is confirmed for the first time by the X-ray crystal structure of the bound Pd2+-complex.
Co-reporter:Shyamaprosad Goswami, Nirmal Kumar Das, Krishnendu Aich, Debabrata Sen
Journal of Luminescence 2011 Volume 131(Issue 10) pp:2185-2188
Publication Date(Web):October 2011
DOI:10.1016/j.jlumin.2011.04.050
A new macrocyclic receptor 1 having [1,8]-naphthyridine fluorophore is designed and synthesized for selective fluorescence sensing of Cd2+. Receptor 1 selectively responds to Cd2+ over other tested metal ions via a large enhancement of emission intensity due to the cation-induced CHEF (chelation enhanced fluorescence) effect. Receptor 1 although exhibits some affinity towards Zn2+, it selectively binds Cd2+ over Zn2+. Binding and selectivity were examined by 1H-NMR, fluorescence, UV–vis, mass and IR-spectroscopic techniques.Graphical AbstractHighlights► Macrocyclic receptor 1 is designed and synthesized. ► [1,8]-naphthyridine is used as fluorophore in 1. ► Results show 1 selectively responds to Cd2+ over other tested metal ions.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen and Nirmal Kumar Das
Organic Letters 2010 Volume 12(Issue 4) pp:856-859
Publication Date(Web):January 27, 2010
DOI:10.1021/ol9029066
A new 1,8-diaminonaphthalene based ratiometric and highly selective colorimetric “off-on” type of fluorescent probe, receptor 2 has been designed and synthesized that senses only Cu2+ among the other heavy and transition metal ions examined on the basis of internal charge transfer (ICT). The visual sensitivity of the receptor 2 is remarkable, showing dual color changes from colorless (receptor) to purple followed by blue and a large red shift in emission upon Cu2+ complexation.
Co-reporter:Kumar Biradha, Suman Samai, Annada C. Maity and Shyamaprosad Goswami
Crystal Growth & Design 2010 Volume 10(Issue 2) pp:937
Publication Date(Web):December 10, 2009
DOI:10.1021/cg9012685
Single crystal X-ray structures of new perchlorate salts of a series of four xanthine alkaloids, for example, xanthine (xt), caffeine (cf), theophylline (tp), and theobromine (tb) are reported. The treatment of xanthine derivatives with 70% of HClO4 afforded their salts Hxt·ClO4·2(H2O), 1; Htp·ClO4, 2; Htb·ClO4, 3; and Hcf·ClO4·H2O, 4. Xanthine form dimers via N(9)−H···O−C(6) hydrogen bond in the crystal structure. Of the two possible resonance structures of the protonated imidazoles, one of the structures was found to be major in xanthine, theobromine, and caffeine salts, while both structures are of equal contribution in theophylline salts. These observations also have been verified by using the structural information available in the Cambridge Structural Database. Interestingly, xanthine 1 is present as a dihydrate and 4 as a monohydrate, whereas 2 and 3 are crystallized without any water. Thus, proton transfer from the strong acid HClO4 to the weakly basic imidazole ring of xanthines occurs which leads to the build up of H-bonded supramolecular networks.
Co-reporter:Shyamaprosad Goswami ;Rinku Chakrabarty
European Journal of Organic Chemistry 2010 Volume 2010( Issue 20) pp:3791-3795
Publication Date(Web):
DOI:10.1002/ejoc.201000142
Abstract
Phenanthroline-based colorimetric sensors 1 and 2 have been designed, synthesized, and compared with phenanthrene-based receptor 3 for sensing of Pb2+ by color change. Receptor 1 imparts color change (from yellow to red) selectively with Pb2+ in acetonitrile/water (9:1) as well as in methanol/water (9:1) when in the presence of other metal ions studied (Li+, Na+, K+, Ca2+, Mg2+, Ba2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Mn2+ as their perchlorate salts). Receptor 1 also shows fluorescence enhancement upon addition of lead perchlorate in acetonitrile/water (9:1) solvent possibly due to the chelation enhanced fluorescence (CHEF) effect. However, the binding behavior of 2 with Pb2+ is found to be less effective compared to that of receptor 1.
Co-reporter:Shyamaprosad Goswami ;Rinku Chakrabarty
European Journal of Organic Chemistry 2010 Volume 2010( Issue 26) pp:
Publication Date(Web):
DOI:10.1002/ejoc.201001053
No abstract is available for this article.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Nirmal Kumar Das, Giridhari Hazra
Tetrahedron Letters 2010 Volume 51(Issue 42) pp:5563-5566
Publication Date(Web):20 October 2010
DOI:10.1016/j.tetlet.2010.08.048
A 1,8-naphthalimide-based colorimetric fluorescence perinone dye, receptor 1 is reported herein for the selective detection of Cu2+ over the other heavy and transition metal ions. Receptor 1 shows a strong colorimetric change from orange to purple and a dramatic enhancement of fluorescence intensity due to cation-induced excited state internal charge transfer during the sensing event, that is, a dual optical response that would facilitate naked-eye detection of Cu2+.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Nirmal Kumar Das
Tetrahedron Letters 2010 Volume 51(Issue 51) pp:6707-6710
Publication Date(Web):22 December 2010
DOI:10.1016/j.tetlet.2010.10.034
A Cu(II) based conformationally restricted chiral fluorescence sensor (receptor 2) has been designed and synthesized for selective sensing of anions. The anion recognition property of the Cu2+-complex has been studied in acetonitrile by fluorescence methods which show remarkable sensitivity toward dihydrogen phosphate via fluorescence modulation of the Cu2+-complex over the other anions examined.
Co-reporter:Shyamaprosad Goswami, Anita Hazra, Manas Kumar Das
Tetrahedron Letters 2010 Volume 51(Issue 25) pp:3320-3323
Publication Date(Web):23 June 2010
DOI:10.1016/j.tetlet.2010.04.085
A designed sensor, selenodiazole-fused pyrimidine ring having two acetylamino groups at 2,4-positions has been synthesized for selective recognition of aliphatic monocarboxylate anions over a wide range of other anions. The recognition study has been carried out by UV–vis and fluorescence methods. A significant bathochromic shift of the fluorescence intensity of the receptor in the presence of carboxylate makes the receptor a discriminating sensor for aliphatic monocarboxylates.
Co-reporter:Shyamaprosad Goswami, Anita Hazra, Rinku Chakrabarty and Hoong-Kun Fun
Organic Letters 2009 Volume 11(Issue 19) pp:4350-4353
Publication Date(Web):September 3, 2009
DOI:10.1021/ol901737s
A selenium metal-based new fluorescence sensor 5-pivaloylamino-1,2,5-selenodiazolo[3,4-d]pyrimidin-7-(6H)-one (receptor 1) has been reported for the recognition of monocarboxylic acids and carboxylate anions both by UV−vis and fluorescence methods. Receptor 1 recognizes carboxylate anions more than monocarboxylic acids and it is a selective sensor for carboxylates with specially hindered carboxylate anions. The changes of fluorescence intensity are remarkably enhanced with red shift in presence of bulky carboxylate anions. The X-ray crystal structure of receptor 1 with pivalic acid has been reported.
Co-reporter:Shyamaprosad Goswami;Annada C. Maity;Hoong-Kun Fun;Suchada Chantrapromma
European Journal of Organic Chemistry 2009 Volume 2009( Issue 9) pp:1417-1426
Publication Date(Web):
DOI:10.1002/ejoc.200801050
Abstract
An effective synthesis of 2-oxo-1,3-propanedial monohydrate or mesoxaldehyde (6a) and the first synthesis of 2,3-dioxo-1,4-butanedial (18) as a thiane derivative are reported. These first members of the smallest vicinal tri- and tetracarbonyl compounds are stabilized by conversion to thiane derivatives 8, 9, 10, 11, 12, 15 and 19, which can be isolated as long-lived compounds at room temperature. The structures of these novel thianes 8, 10, 12 and 15 were confirmed by their X-ray crystal structures. The synthesis of a series of protected as well as free heterocyclic aldehydes (pterins and quinoxalines) by the use of the appropriate tricarbonyl compounds is also reported. Additionally, a one-step synthetic strategy to prepare a series of different biheterocycles with the smallest vicinal tetracarbonyl compound is demonstrated.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Co-reporter:Shyamaprosad Goswami;Nirmal Kumar Das
Journal of Heterocyclic Chemistry 2009 Volume 46( Issue 2) pp:324-326
Publication Date(Web):
DOI:10.1002/jhet.71
Co-reporter:Shyamaprosad Goswami;Anita Hazra ;Subrata Jana
Journal of Heterocyclic Chemistry 2009 Volume 46( Issue 5) pp:861-865
Publication Date(Web):
DOI:10.1002/jhet.148
Co-reporter:Shyamaprosad Goswami, Rinku Chakrabarty
Tetrahedron Letters 2009 50(43) pp: 5910-5913
Publication Date(Web):
DOI:10.1016/j.tetlet.2009.08.011
Co-reporter:Shyamaprosad Goswami, Rinku Chakrabarty
Tetrahedron Letters 2009 50(44) pp: 5994-5997
Publication Date(Web):
DOI:10.1016/j.tetlet.2009.08.021
Co-reporter:Ajit Kumar Mahapatra, Prithidipa Sahoo, Shyamaprosad Goswami, Suchada Chantrapromma, Hoong- Kun Fun
Tetrahedron Letters 2009 50(1) pp: 89-92
Publication Date(Web):
DOI:10.1016/j.tetlet.2008.10.095
Co-reporter:Shyamaprosad Goswami, Subrata Jana, Nirmal K. Das, Hoong-Kun Fun, Suchada Chantrapromma
Journal of Molecular Structure 2008 Volume 876(1–3) pp:313-321
Publication Date(Web):30 March 2008
DOI:10.1016/j.molstruc.2007.07.005
A series of co-crystals containing substituted 2-aminopyrimidines (2AP) with different dicarboxylic acids have been synthesized and their interactive modes have been characterized by single crystal X-ray studies. For this purpose three complexes containing 2-amino-4,6-dimethylpyrimidine and terephthalic acid (complex 1), 2-amino-4-methyl-6-phenylpyrimidine and isophthalic acid (complex 2), 2-amino-4,6-diphenylpyrimidine and terephthalic acid (complex 3) have been synthesized. Substituents of the 2AP ring have been changed carefully from dimethyl, methyl–phenyl to diphenyl in increasing order of their size to study the change in their crystal engineering and overall supramolecular architecture.
Co-reporter:Annada C. Maity;Hoong-Kun Fun
European Journal of Organic Chemistry 2007 Volume 2007(Issue 24) pp:4056-4064
Publication Date(Web):3 JUL 2007
DOI:10.1002/ejoc.200700271
A perchloric acid mediated one-step synthesis of lumazine derivatives from pterins and xanthine from guanine is reported. However, 2-pivaloylamino derivatives of pterins underwent simple hydrolysis of the pivaloylamino group generating free pterin compounds, but the 2-oxo derivatives, that is, the lumazine compounds, were not obtained. A novel supramolecular assembly is constructed by the unique hydrogen bonding of H5O2+ bridging two hydrogen-bonded dimers of lumazine to form the co-crystal 21 with aqueous perchloric acid. In contrast, N2-pivaloyl-6-bromo-5-deazapterin was simply hydrolysed to form the protonated deazapterin 22, which forms a unique six-membered cyclic hydrogen-bonded structure leading to the generation of a polymeric supramolecular assembly. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Co-reporter:Anita Hazra;Subrata Jana;Avijit Kumar Adak
Journal of Heterocyclic Chemistry 2007 Volume 44(Issue 5) pp:1191-1194
Publication Date(Web):13 MAR 2009
DOI:10.1002/jhet.5570440536
A series of functionalized, aryl substituted naphthyridines and quinolines has been synthesized by microwave-assisted one-pot two-component synthesis under solvent-free conditions in good yields by the reaction of a variety of aryl or heteroaryl amines and aryl vinyl ketones. A combinatorial type approach for a one-step microwave reaction has been developed where a ring-closing condensation is followed by a spontaneous aromatization to afford the functionalized aryl substituted 1,8-naphthyridines and quinolines.
Co-reporter:Ibon Alkorta, José Elguero, Shyamaprosad Goswami and Reshmi Mukherjee
Organic & Biomolecular Chemistry 2002 (Issue 5) pp:894-898
Publication Date(Web):10 Apr 2002
DOI:10.1039/B200915N
The interaction of adenine with synthetic macrocyclic receptors has been modelled using, as simplified molecular systems, the monoamide derivatives of pyridine and 1,8-naphthyridine. DFT methods (B3LYP/6-31+G**) have been used to characterise the complexes stabilised by multiple hydrogen bonds. The theoretical results indicate that while the synthetic receptors with pyridines can interact simultaneously forming pseudo-Watson–Crick and pseudo-Hoogsten complexes with adenine, in the case of the 1,8-naphthyridines only one of the complexes is possible. The energetic results that favour the pyridine receptors are in agreement with the experimental binding constants.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Avijit Kumar Das, Nirmal Kumar Das, Krishnendu Aich, Hoong-Kun Fun, Ching Kheng Quah, Anup Kumar Maity, Partha Saha
Sensors and Actuators B: Chemical (5 July 2013) Volume 183() pp:518-525
Publication Date(Web):5 July 2013
DOI:10.1016/j.snb.2013.04.005
A new coumarin containing rhodamine architecture has been synthesized for selective and chromogenic detection of Cu2+ in aqueous media. Cu2+ induced spirocyclic ring opening of the rhodamine dye has been demonstrated by single crystal X-ray structures of the fluorescence probe as well as its bound Cu2+-complex. It is also promising as a Cu2+-selective sensor in the fluorescence imaging of living cells.
Co-reporter:Shyamaprosad Goswami, Shampa Chakraborty, Sima Paul, Sandipan Halder, Sukanya Panja and Subhra Kanti Mukhopadhyay
Organic & Biomolecular Chemistry 2014 - vol. 12(Issue 19) pp:NaN3044-3044
Publication Date(Web):2014/02/21
DOI:10.1039/C4OB00067F
A new pyrene based fluorescence probe has been synthesized for fluorogenic detection of Cu2+ in acetonitrile–aqueous media (7:3 CH3CN–HEPES buffer, v/v, at pH 7.5) with bioimaging in both prokaryotic (Candida albicans cells) and eukaryotic (Tecoma stans pollen cells) living cells. The anion recognition properties of the sensor have also been studied in acetonitrile by fluorescence methods which show remarkable sensitivity toward fluoride over other anions examined.
Co-reporter:Avijit Kumar Das, Shyamaprosad Goswami, Gorachand Dutta, Sibaprasad Maity, Tarun kanti Mandal, Kalyani Khanra and Nandan Bhattacharyya
Organic & Biomolecular Chemistry 2016 - vol. 14(Issue 2) pp:NaN576-576
Publication Date(Web):2015/10/15
DOI:10.1039/C5OB02008E
H2S is shown, for the first time, to play an extraordinary dual role due to its nucleophilicity and reducing property with our single chemosensor, PND [4-(piperidin-1-yl) naphthalene-1,2-dione]. The initial nucleophilic attack via Michael addition (a lower concentration of H2S, blue fluorescence) is followed by the reduction of the 1,2-diketo functionality (a higher concentration of H2S, green fluorescence). This chemosensor, which also shows biological response, is remarkably effective in sensing the same analyte (H2S) at its different concentrations in a relay pathway via a fluorescence “off–on–on” mechanism, and this is also supported by DFT calculation and Cyclic voltammograms.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das and Sibaprasad Maity
Dalton Transactions 2013 - vol. 42(Issue 46) pp:NaN16263-16263
Publication Date(Web):2013/09/13
DOI:10.1039/C3DT52252K
A novel colorimetric and fluorescent chemosensor based on 7-(diethylamino)-3-(pyrimidin-4-yl)-2H-chromen-2-one (PYC) has been designed and synthesized for the detection of Hg2+ in the presence of other competing metals in mixed aqueous media. The PYC exhibits naked eye color change from green to red, and the fluorescence color changes from yellowish green to light orange with Hg2+. It also shows a red shift in wavelength of about 80 nm in absorption spectra. Test strips based on PYC were fabricated, which could act as convenient and efficient Hg2+ test kits.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Anup Kumar Maity, Sima Paul, Avijit Kumar Das, Manas Kumar Das, Partha Saha, Ching Kheng Quah and Hoong-Kun Fun
Dalton Transactions 2013 - vol. 42(Issue 36) pp:NaN12848-12848
Publication Date(Web):2013/07/12
DOI:10.1039/C3DT51591E
A new rhodamine based chemosensor, cyano-rhodamine, has been designed and synthesized with a green approach which shows a specific ‘C–CN’ bond breaking with the action of the Pd2+ ion to produce the specific color and fluorescence of rhodamine 6G itself in solution and in HeLa cells.
Co-reporter:Shymaprosad Goswami, Abhishek Manna, Sima Paul, Avijit K. Das, Krishnendu Aich and Prasanta K. Nandi
Chemical Communications 2013 - vol. 49(Issue 28) pp:NaN2914-2914
Publication Date(Web):2013/02/21
DOI:10.1039/C3CC39256B
For ratiometric “naked eye” detection of CN−, an ESIPT exhibiting benzothiazole receptor (BHI) is designed having one aldehyde group ortho and the other aldehyde para to the OH group respectively. Due to RAHBs, the ortho aldehyde group is highly reactive undergoing nucleophilic cyanide addition selectively, which hampered ESIPT. This is also supported by DFT and TD-DFT calculations.
Co-reporter:Shymaprosad Goswami, Krishnendu Aich, Sangita Das, Avijit Kumar Das, Deblina Sarkar, Sukanya Panja, Tapan Kumar Mondal and Subhrakanti Mukhopadhyay
Chemical Communications 2013 - vol. 49(Issue 91) pp:NaN10741-10741
Publication Date(Web):2013/09/27
DOI:10.1039/C3CC46860G
A spirobenzopyran-quinoline (SBPQ) based sensor was synthesized which selectively detects trivalent ions viz. Al3+, Fe3+ and Cr3+ through a fluorescence turn on signal in the red region (∼675 nm) with the detection limit in the order of 10−8 M. The potentiality of the probe was confirmed by employing it for fluorescence bio-imaging with Al3+ in three different types of live-cells.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Ching Kheng Quah and Hoong-Kun Fun
Chemical Communications 2013 - vol. 49(Issue 99) pp:NaN11658-11658
Publication Date(Web):2013/10/18
DOI:10.1039/C3CC47121G
We have designed a chemodosimeter DPNO (weak fluorescence) which can be oxidized to HPNO (strong blue fluorescence) by OCl− with high selectivity and sensitivity in a ratiometric approach with a noticeably lower detection limit. The sensor could be useful for the detection of hypochlorites in tap water.
Co-reporter:Shyamaprosad Goswami, Debabrata Sen, Nirmal Kumar Das, Hoong-Kun Fun and Ching Kheng Quah
Chemical Communications 2011 - vol. 47(Issue 32) pp:NaN9103-9103
Publication Date(Web):2011/07/05
DOI:10.1039/C1CC12845K
A new fluorescence rhodamine derivative bearing an 8-aminoquinoline moiety has been designed and synthesized for selective sensing of Pd2+ in the presence of other competing metal ions in aqueous media. Pd2+ induced spirolactam ring opening of rhodamine is confirmed for the first time by the X-ray crystal structure of the bound Pd2+-complex.
Co-reporter:Shyamaprosad Goswami, Krishnendu Aich, Sangita Das, Chitrangada Das Mukhopadhyay, Deblina Sarkar and Tapan Kumar Mondal
Dalton Transactions 2015 - vol. 44(Issue 12) pp:NaN5770-5770
Publication Date(Web):2015/02/10
DOI:10.1039/C4DT02463J
A new quinoline based sensor was developed and applied for the selective detection of Cd2+ both in vitro and in vivo. The designed probe displays a straightforward approach for the selective detection of Cd2+ with a prominent fluorescence enhancement along with a large red shift (∼38 nm), which may be because of the CHEF (chelation-enhanced fluorescence) and ICT (internal charge transfer) processes after interaction with Cd2+. The interference from other biologically important competing metal ions, particularly Zn2+, has not been observed. The visible-light excitability of the probe merits in the viewpoint of its biological application. The probe enables the detection of intracellular Cd2+ with non-cytotoxic effects, which was demonstrated with the live RAW cells. The experimentally observed change in the structure and electronic properties of the sensor after the addition of Cd2+ were modelled by the density functional theory (DFT) and time-dependent density functional theory (TDDFT) computational calculations, respectively. Moreover, the test strip experiment with this sensor exhibits both absorption and fluorescence color changes when exposed to Cd2+ in a mixed aqueous solution, which also makes the probe more useful. The minimum limit of detection of Cd2+ by the probe was in the range of 9.9 × 10−8 M level.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Anup Kumar Maity, Abhishek Manna, Krishnendu Aich, Sibaprasad Maity, Partha Saha and Tarun Kanti Mandal
Dalton Transactions 2014 - vol. 43(Issue 1) pp:NaN239-239
Publication Date(Web):2013/09/16
DOI:10.1039/C3DT51851E
A new spirobenzopyran derivative (SPNH) was designed and synthesized which was applied in simultaneous colorimetric and NIR fluorescence detections for Cr3+. This spirobenzopyran receptor is normally colorless in aqueous organic media but the formation of merocyanine occurs by Cr3+ showing a yellow color. Here the formation of yellow color in UV-vis spectra and strong NIR fluorescence emission at 675 nm makes SPNH a good sensor for Cr3+ ion. It is also found to be useful in cell imaging and in construction of logic gate. It shows INHIBIT gate in fluorescence and OR gate in absorption. To the best of our knowledge, this is the first report of NIR fluorescence emission of a spirobenzopyran derivative by Cr3+ and its application to cell-biology and also in the logic gate.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
Dalton Transactions 2013 - vol. 42(Issue 30) pp:NaN10686-10686
Publication Date(Web):2013/06/10
DOI:10.1039/C3DT51262B
A hybrid carbazole hemicyanine dye (receptor CHD) was developed as a new visible and near infrared chemodosimeter type sensor with high ratiometric selectivity towards cyanide in the presence of other anions in aqueous solution. The chemosensor also showed excellent performance when used in the “dip stick” method, i.e. in solid phase (TLC plates).
Co-reporter:Shyamaprosad Goswami, Sangita Das, Krishnendu Aich, Deblina Sarkar, Tapan Kumar Mondal, Ching Kheng Quah and Hoong-Kun Fun
Dalton Transactions 2013 - vol. 42(Issue 42) pp:NaN15119-15119
Publication Date(Web):2013/08/13
DOI:10.1039/C3DT51974K
A new fluorescent probe was synthesized from rhodamine-6G and 6-(hydroxymethyl) picolinohydrazide for the sensing of Fe3+ in an aqueous environment. The structure of the sensor was confirmed through its single crystal X-ray study. It exhibits a high specificity and sensitivity towards Fe3+ over other interfering heavy and transition metal ions (HTM). The turn-on greenish-yellow fluorescence and a colorimetric change from colourless to pink were observed upon addition of Fe3+ which evokes almost 116- and 23-fold enhancement in absorbance and emission intensity respectively in an acetonitrile–water (1:1, v/v, 25 °C) solution at a neutral pH (pH = 7.2). The Fe3+ promoted ring opening of the spirolactam framework to the open chain amide platform of the sensor is responsible for its visible colour change and turn-on fluorescence activity. It also exhibits an excellent performance in the “dip stick” method. Moreover the limit of detection of the probe is in the 10−8 M range.
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Urmila Saha, Sibaprasad Maity, Kalyani Khanra and Nandan Bhattacharyya
Organic & Biomolecular Chemistry 2015 - vol. 13(Issue 7) pp:NaN2139-2139
Publication Date(Web):2014/12/05
DOI:10.1039/C4OB01842G
Our designed and synthesized chemosensor naphthalene based chromenyl derivative (NAC) [1-(3-hydroxy-3 methyl-3H-benzo[f]chromen-2-yl) ethanone] has been used for fast (<30 s, DL = 0.22 ppb) and selective detection of N2H4 by a new way via the chromenyl ring opening followed by the pyrazole ring formation giving a strong blue fluorescence. The DFT study and the real application in different water samples along with the dipstick method in low cost devices have also been performed here. Human lung cancer cells (NCI-H460) have been used for hydrazinolysis of the NAC in vivo system for detection by the appearance of blue fluorescence and also for the MTT assay showing its remarkable cancer sensitivity.
Co-reporter:Shyamaprosad Goswami, Sima Paul and Abhishek Manna
Dalton Transactions 2013 - vol. 42(Issue 28) pp:NaN10101-10101
Publication Date(Web):2013/05/16
DOI:10.1039/C3DT51238J
The de-diaminomaleonitrile reaction in a simple carbazole diaminomaleonitrile hybrid (CDH) was promoted by OCl− which disrupted the ICT mechanism by breaking the donor and acceptor linkage. This system utilized an irreversible OCl− promoted oxidation reaction and it responded instantaneously at room temperature. The chemosensor also showed excellent performance in tap water and the “dip-stick” method.
Co-reporter:Shyamaprosad Goswami, Abhishek Manna, Sima Paul, Krishnendu Aich, Avijit K. Das and Shampa Chakraborty
Dalton Transactions 2013 - vol. 42(Issue 22) pp:NaN8085-8085
Publication Date(Web):2013/03/12
DOI:10.1039/C3DT50621E
In this study, we have synthesized a simple Schiff base type isophthaloyl salicylaldehyde hydrazone (ISH) moiety which selectively detects Al(III) and PPi with a fluorescence enhancement at two different wavelengths in aqueous solution. The sensing phenomenon is also reversible and thus the sensor beautifully mimics logic gates (INHIBIT and EXOR gates).
Co-reporter:Shyamaprosad Goswami, Avijit Kumar Das, Bholanath Pakhira, Sohini Basu Roy, Anup Kumar Maity, Partha Saha and Sabyasachi Sarkar
Dalton Transactions 2014 - vol. 43(Issue 33) pp:NaN12697-12697
Publication Date(Web):2014/06/23
DOI:10.1039/C4DT01262C
A new zinc(II) complex with a condensed hydroxynaphthyl pyridine (SPHN) as the coordinated ligand has been synthesized for the selective recognition of pyrophosphate (PPi) over other anions including phosphate in a mixed aqueous solution. The fluorescence enhancement of SPHN in association with Zn2+ ions is quenched in the presence of intracellular pyrophosphate. This phenomenon is utilized in the construction of a logic gate. The binding of SPHN with Zn2+ and its displacement by PPi have been established by photophysical investigation and supported by the DFT level of studies. The development of blue fluorescence in the {SPNH–Zn} complex upon binding of zinc with SPHN is shown to be useful as a nucleus marker in a cell similar to the commercially available staining compound, DAPI (diamino-2-phenylindole).
Co-reporter:Sima Paul, Abhishek Manna and Shyamaprosad Goswami
Dalton Transactions 2015 - vol. 44(Issue 26) pp:NaN11810-11810
Publication Date(Web):2015/05/19
DOI:10.1039/C5DT01314C
A chemosensor was developed which could selectively detect and differentiate trivalent metal ions (Al3+, Cr3+ and Fe3+) upon single excitation at two different wavelengths in aqueous medium. This probe selectively detects trivalent ions in the presence of different metal ions in aqueous medium. It shows an excellent performance in the “dipstick” method.
