A novel styrylcyanine-based fluorescent probe 1 was designed and synthesized via facile methods. Ferric ions quenched the fluorescence of probe 1, whereas the addition of ferrous ions led to only small changes in the fluorescence signal. When hydrogen peroxide was introduced into the solution containing probe 1 and Fe²⁺, Fe²⁺ was oxidized to Fe³⁺, resulting in the quenching of the fluorescence. The probe 1/Fe²⁺ solution fluorescence could also be quenched by H₂O₂ released from glucose oxidation by glucose oxidase (GOD), which means that probe 1/Fe²⁺ platform could be used to detect glucose. Probe 1 is fluorescent in basic and neutral media but almost non-fluorescent in strong acidic environments. Such behaviour enables it to work as a fluorescent pH sensor in both the solution and solid states and as a chemosensor for detecting volatile organic compounds with high acidity and basicity. Subsequently, the fluorescence microscopic images of probe 1 in live cells and in zebrafish were achieved successfully, suggesting that the probe has good cell membrane permeability and a potential application for imaging in living cells and living organisms. Copyright © 2014 John Wiley & Sons, Ltd.

Novel chiral methylpropargyl esters bearing azobenzene groups, namely, 4-[4′-(benzyloxy)phenylazophenyl]- carbonyl-(S)-1-methylpropargyl ester (e), 4-[4′-(n-butyloxy)phenylazophenyl]carbonyl-(S)-1-methylpropargyl ester (f), 4-[4′-(n-hexyloxy)phenylazophenyl]carbonyl-(S)-1-methylpropargyl ester (g), and 4-[4′-(n-octyloxy)phenylazo- phenyl]carbonyl-(S)-1-methylpropargyl ester (h) were synthesized and polymerized with Rh⁺(nbd)[η⁶-C₆H₅B⁻- (C₆H₅)₃] (nbd=norbornadiene) catalyst to give the corresponding polymers with moderate molecular weights (M_n=8.4×10³–15.7×10³) in good yields (76%? –?91%). The structures of polymers were illustrated by IR and NMR spectroscopies. Polymers were soluble in comment organic solvents including toluene, CHCl₃ CH₂Cl₂, THF, and DMSO, while insoluble in diethyl ether, n-hexane and methanol. Large optical rotations of polymer solutions demonstrated that all the polymers take a helical structure with a predominantly one-handed screw sense in organic solvents.

Optically active 1-methylpropargyl esters bearing azobenzene groups, namely, (S)-(−)-3-methyl-3-{4-[4-(n-butyloxy)phenylazophenyl]carbonyl}oxy-1-propyne (1), (S)-(−)-3-methyl-3-{4-[4-(n-hexyloxy)phenylazophenyl]carbonyl}oxy-1-propyne (2), and (S)-(−)-3-methyl-3-{4-[4-(n-octyloxy)phenylazophenyl]carbonyl}oxy-1-propyne (3) were synthesized and polymerized with Rh⁺(nbd)[η⁶-C₆H₅B⁻(C₆H₅)₃] (nbd, norbornadiene) as a catalyst to afford the corresponding poly(1-methyloropargyl ester)s with moderate molecular weights (M_n = 24,000–31,300) in good yields (79–84%). Polymers were soluble in common organic solvents including toluene, CHCl₃, CH₂Cl₂, THF, and DMSO, whereas insoluble in diethyl ether, n-hexane, and methanol. Large optical rotations and strong CD signals demonstrated that all the polymers take a helical structure with a predominantly one-handed screw sense. The helical structure of the polymers changed with the addition of MeOH and heat. The trans-azobenzene of the polymer side chains isomerized into cis on UV irradiation, which was accompanied with drastic helical conformational changes of the polymer backbone. The cis-azobenzene moiety reisomerized into trans on visible-light irradiation, which induced the recovery of chiral geometry of azobenzene moieties in the side chain. Conformational analysis revealed that the polymers form a tightly twisted right-handed helical structure with a dihedral angle of 70° at the single bond of the main chain. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4749–4761, 2009