Seven new azacyclo-indoles and phenolics and four known alkaloids were isolated from the flowers of Juglans regia. Spectroscopic and chromatographic data revealed that the structures of the new compounds are 5,6,11,12-tetrahydropyrrolo[1′,2′:1,2]azepino[4,5-b]indole-3-carbaldehyde (1), (±)-5,6,7,11c-tetrahydro-1H-indolizino[7,8-b]indol-3(2H)-one (2), (±)-9-hydroxy-5-oxo-2,3,4,5-tetrahydro-1H-benzo[b]azepine-2-carboxamide (3), 5-(ethoxymethyl)-1-(4-hydroxyphenethyl)-1H-pyrrole-2-carbaldehyde (4), (±)-5,8-dihydroxy-4-(1H-indol-3-yl)-3,4-dihydronaphthalen-1(2H)-one (5), (±)-4-(6-amino-9H-purin-9-yl)-5,8-dihydroxy-3,4-dihydronaphthalen-1(2H)-one (6), and (±)-4-(6-amino-9H-purin-9-yl)-5-hydroxy-3,4-dihydronaphthalen-1(2H)-one (7). The five pairs of enantiomers were resolved, and the absolute configurations of the enantiomers were assigned via electronic circular dichroism data. Compound 1 exhibited significant in vitro growth inhibition against the HCT-116, HepG2, BGC-823, NCI-H1650, and A2780 cancer cell lines, with IC50 values of 2.87, 1.87, 2.28, 2.86, and 0.96 μM, respectively, and low cytotoxicity toward normal IEC-6 cells, with a 79.6% survival rate at a 10 μM concentration.

•Six pairs of enantiomeric alkaloids were isolated from Chelidonium majus.•Scalemic mixtures were characterized via chiral HPLC analysis and ECD data.•Absolute configurations were assigned via resolution and ECD data.•Active compound inhibited the growth of human MDA-MB-231 cell line.•Relevant biochemical reactions in C. majus are very nonselective.Six pairs of previously undescribed 6-monosubstituted dihydrobenzophenanthridine alkaloids were separated as corresponding six scalemic mixtures from the aerial part of Chelidonium majus. The elucidation for the 2D structures of these alkaloids was achieved using regular spectroscopic and chemical methods. The assignment of scalemic-mixture nature was achieved using combined examinations of their NMR data, CD spectra, calculation of specific rotations, and chiral HPLC profiles. The identification for the relative configurations of alkaloids possessing two asymmetric carbons directly connected up by a rotatable sp3-sp3 carbon-carbon single bond was significantly facilitated by discussing the erythro and threo relative configurations defined by the mutuality of the orders of decreasing steric hindrances between the two sets of ligands linked to the two chiral centers. Two scalemic mixtures were assigned as (1′R,6R/1′S,6S)- and (1′S,6R/1′R,6S)-1-(dihydrochelerythrine-6-yl)ethanols, two as (1′R,6R)/(1′S,6S)- and (1′S,6R)/(1′R,6S)-1-(dihydrosanguinarine-6-yl)ethanols, one as (±)-ethyl 2-(dihydrosanguinarine-6-yl)acetate, and one as (±)-ethyl dihydrosanguinarine-6-carboxylate, respectively. The resolution of three scalemic mixtures was achieved and the absolute configurations of the three pairs of enantiomers were assigned via time-dependent Density Functional Theory calculations of electronic circular dichroism (ECD) data. The assignment for the absolute configurations of the other three scalemic mixtures was achieved via a chiral HPLC-UV/CD method plus analyzing their ECD data. The findings of this paper demonstrated that the relevant biochemical reactions concerning the construction of these 6-monosubstituted dihydrobenzophenanthridine alkaloids in the test plant are very nonselective. Scalemic mixture of (1′R,6R)/(1′S,6S)-1-(dihydrosanguinarine-6-yl)ethanol exhibited biological activity. It inhibited the growth of human MDA-MB-231 cell line at a moderate level with IC50 value of 5.12 μM.Six previously undescribed 6-monosubstituted dihydrobenzophenanthridine alkaloids were identified from C. majus, all characterizec as scalemic mixtures of enantiomers. Resolution and identification of absolute configurations were achieved.Download high-res image (209KB)Download full-size image

•Nine 14,15-secopregnane-type C21-steriosides were isolated from Cynanchum stauntonii.•An unusual 14,15-secopregnane with 5:9-peroxy bridge moiety was characterized.•Two sugar moieties composed of deoxysugars were characterized.•Active compounds selectively inhibited production of nitric oxide.•Bioactive C21-steriosides underlie the traditional application of C. stauntonii.Nine 14,15-secopregnane-type C21-steriosides, stauntosides U, V, V1-V3, W and C1-C3, as well as two known C21-steriosides, were isolated from the roots of Cynanchum stauntonii. Stauntosides U, V and V1-V3 share the same basic structural features of 8α:14α,14:16,15:20,18:20-tetraepoxy-14,15-secopregn-6-ene-3β,5α,9α-triol, with the numbering system following that of C21-pregnanes. The aglycones of stauntosides U, V and V1-V3 are classified into two subcategories, the 5,9-dihydroxy groups and 5α:9α-peroxy bridge, according to the oxidative states of the two hydroxy groups at the C-5 and C-9 positions. The anti-inflammatory activity of the major compounds was assessed in an in vitro inflammatory model of mouse peritoneal macrophages using IC50 values of the inhibition of nitric oxide (NO) production as an indicator. Stauntosides V1 and V3 exhibited target activity with IC50 values of 9.3 μM and 12.4 μM, respectively, compared with dexamethasone, which was used as a positive control.IC50 of anti-inflammatory activies: stauntoside V1 12.4 μM; stauntoside V3 9.3 μM.Download high-res image (141KB)Download full-size image

There is a severe lack of effective treatments for ulcerative colitis (UC), a recurrent and intractable inflammatory bowel disease. The identification of valid targets and new drugs is an urgent need. In this study, we identified the XBP-1 agonist HLJ2 as a promising treatment candidate. In an in vivo mouse model of DSS-induced colitis, HLJ2 decreased weight loss, colon contracture, disease activity index (DAI), colon mucosa damage index (CMDI) and histopathological index (HI). HLJ2 also decreased myeloperoxidase (MPO) activity and reduced production of the inflammatory cytokines TNF-α, IL-1β, and IL-6. HLJ2 improved intestinal mucosa damage induced by dextran sodium sulfate (DSS) and increased the expression of ZO-1 and claudin-1. Fecal 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2, including increased abundance of probiotics such as Lachnospiraceae, Prevotellaceae, and Lactobacillaceae. At the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae, Porphyromonadaceae, Deferribacteraceae, and Pseudomonadaceae in HLJ2-treated mice compared with untreated mice. Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation, regulates the intestinal flora, and protects the intestinal mucosa. It is thus a potential therapeutic agent for ulcerative colitis.Download high-res image (81KB)Download full-size image

There is a severe lack of effective treatments for ulcerative colitis (UC), a recurrent and intractable inflammatory bowel disease. The identification of valid targets and new drugs is an urgent need. In this study, we identified the XBP-1 agonist HLJ2 as a promising treatment candidate. In an in vivo mouse model of DSS-induced colitis, HLJ2 decreased weight loss, colon contracture, disease activity index (DAI), colon mucosa damage index (CMDI) and histopathological index (HI). HLJ2 also decreased myeloperoxidase (MPO) activity and reduced production of the inflammatory cytokines TNF-α, IL-1β, and IL-6. HLJ2 improved intestinal mucosa damage induced by dextran sodium sulfate (DSS) and increased the expression of ZO-1 and claudin-1. Fecal 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2, including increased abundance of probiotics such as Lachnospiraceae, Prevotellaceae, and Lactobacillaceae. At the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae, Porphyromonadaceae, Deferribacteraceae, and Pseudomonadaceae in HLJ2-treated mice compared with untreated mice. Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation, regulates the intestinal flora, and protects the intestinal mucosa. It is thus a potential therapeutic agent for ulcerative colitis.Download high-res image (81KB)Download full-size image

There is a severe lack of effective treatments for ulcerative colitis (UC), a recurrent and intractable inflammatory bowel disease. The identification of valid targets and new drugs is an urgent need. In this study, we identified the XBP-1 agonist HLJ2 as a promising treatment candidate. In an in vivo mouse model of DSS-induced colitis, HLJ2 decreased weight loss, colon contracture, disease activity index (DAI), colon mucosa damage index (CMDI) and histopathological index (HI). HLJ2 also decreased myeloperoxidase (MPO) activity and reduced production of the inflammatory cytokines TNF-α, IL-1β, and IL-6. HLJ2 improved intestinal mucosa damage induced by dextran sodium sulfate (DSS) and increased the expression of ZO-1 and claudin-1. Fecal 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2, including increased abundance of probiotics such as Lachnospiraceae, Prevotellaceae, and Lactobacillaceae. At the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae, Porphyromonadaceae, Deferribacteraceae, and Pseudomonadaceae in HLJ2-treated mice compared with untreated mice. Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation, regulates the intestinal flora, and protects the intestinal mucosa. It is thus a potential therapeutic agent for ulcerative colitis.Download high-res image (81KB)Download full-size image

There is a severe lack of effective treatments for ulcerative colitis (UC), a recurrent and intractable inflammatory bowel disease. The identification of valid targets and new drugs is an urgent need. In this study, we identified the XBP-1 agonist HLJ2 as a promising treatment candidate. In an in vivo mouse model of DSS-induced colitis, HLJ2 decreased weight loss, colon contracture, disease activity index (DAI), colon mucosa damage index (CMDI) and histopathological index (HI). HLJ2 also decreased myeloperoxidase (MPO) activity and reduced production of the inflammatory cytokines TNF-α, IL-1β, and IL-6. HLJ2 improved intestinal mucosa damage induced by dextran sodium sulfate (DSS) and increased the expression of ZO-1 and claudin-1. Fecal 16s rRNA high-throughput sequencing demonstrated a significant improvement in UC intestinal dysbacteriosis in mice treated with HLJ2, including increased abundance of probiotics such as Lachnospiraceae, Prevotellaceae, and Lactobacillaceae. At the same time there was a reduction in the abundance of pathogenic or conditional pathogenic microorganisms such as Bacteroidaceae, Porphyromonadaceae, Deferribacteraceae, and Pseudomonadaceae in HLJ2-treated mice compared with untreated mice. Our results demonstrated that the XBP1 agonist HLJ2 inhibits inflammation, regulates the intestinal flora, and protects the intestinal mucosa. It is thus a potential therapeutic agent for ulcerative colitis.Download high-res image (81KB)Download full-size image

In this study, natural quaternary coptisine was used as a lead compound to design and synthesize structurally stable and actively potent coptisine analogues. Of the synthesized library, 13 N-dihydrocoptisine-8-ylidene amines/amides were found not only to be noncytotoxic toward intestinal epithelial cells (IECs), but they were also able to activate the transcription of X-box-binding protein 1 (XBP1) targets to varying extents in vitro. Antiulcerative colitis (UC) activity levels were assessed at the in vitro molecular level as well as in vivo in animals using multiple biomarkers as indices. In an in vitro XBP1 transcriptional activity assay, four compounds demonstrated good dose–effect relationships with EC50 values of 0.0708–0.0132 μM. Moreover, two compounds were confirmed to be more potent in vivo than a positive control, demonstrating a curative effect for UC in experimental animals. Thus, the findings of this study suggest that these coptisine analogues are promising candidates for the development of anti-UC drugs.

⿢More information on the chemical constituents of Chelidonium majus are described.⿢Two new hopane-type triterpenes were characterized.⿢Hopane-type triterpenes were isolated from C. majus for the first time.⿢The isopropyl in hopane core was manifested by an acrylic acid-2-yl as a shared feature.Two new hopane-type triterpenes, 1-oxo-3α-hydroxy-22(30)-hopen-29-oic acid (1) and 3α-hydroxy-22(30)-hopen-29-oic acid (2), and the known compounds dihydrosanguinarine (3), dl-stylopine (4), dihydrochelirubine (5), dihydromacarpine (6), dihydrochelerythrine (7), dihydrochelilutine (8), and norsanguinarine (9) were isolated from the aerial part of Chelidonium majus. The structures of the new compounds were elucidated based on extensive spectroscopic evidence, especially from 1D and 2D NMR and HRESIMS experiments. The shared structure features of the hopane-type triterpenes are the presence of a mono-hydroxyl substitution at the 3-position and an acrylic acid-2-yl moiety, as a manifestation of the isopropyl group connected to C-21 of the hopane skeleton. Phytotaxonomically, the hopane-type triterpenes might be another important chemical marker in addition to the benzophenanthridine alkaloids of C. majus.

Thirty quaternary coptisine derivatives from a synthesized library were found to activate the in vitro transcription of x-box-binding protein 1 (XBP1). Among these, the dihydrocoptisines were demonstrated by in vitro XBP1 transcriptional activity assays and animal experiments to be much more active anti-ulcerative colitis (UC) agents than quaternary coptisines, tetrahydrocoptisines, and the positive control. Unsubstituted dihydrocoptisine exhibited more significant anti-UC efficacy than dihydrocoptisines substituted at the C-8 or C-13 position. The EC50 value of dihydrocoptisine for XBP1 transcriptional activation was 2.25 nM. Dihydrocoptisine exhibited a significant dose–effect relationship, as indicated by biomarkers in in vitro and in vivo experiments. According to this study, the starting material’s reductive states and the substitution patterns of the dihydrocoptisines were determined to be the critical parameters for modulating their anti-UC efficacy, and the dihydrocoptisine skeleton was designated as the key pharmacophore. The synthesized dihydrocoptisine is a promising lead for developing anti-UC drugs.

Eight new cembranoids, boscartins A–H (1, 2, and 4–9), and the known incensole oxide were isolated from the gum resin of Boswellia carterii. The absolute configurations of 1, 2, 4, and incensole oxide were unequivocally resolved using single-crystal X-ray diffraction analysis with Cu Kα radiation, and the absolute configuration of 5 was resolved via electronic circular dichroism data. The antiulcerative colitis activities of the compounds were evaluated in an in vitro x-box-binding protein 1 (XBP 1) transcriptional activity assay using dual luciferase reporter detection. At 10 μM, compounds 1, 5, 6, and 7 significantly activated XBP 1 transcription with EC50 values of 0.34, 1.14, 0.88, and 0.42 μM, respectively, compared with the pGL3-basic vector control.

•More information on the chemical constituents of Ephedra sinica are described.•Five new acetamide glycosides were characterized.•The N,N-bissubstituted acetamides showed obvious rotamerism in solution.Five new N-mono-/bis-substituted acetamide glycosides, N-{4-O-[3-O-(4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (1), N-methyl-N-{4-O-[3-O-(4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (2), N-methyl-N-{4-O-[3-O-(6-O-benzoyl-4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (3), N-methyl-N-{4-O-[3-O-(6-O-benzoyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (4), and N-methyl-N-{4-O-[3-O-(6-O-trans-cinnamoyl-4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (5), along with one known acetamide derivative, N-methyl-N-(4-hydroxyphenethyl)-acetamide, the shared aglycone of 2–5, were isolated from the ethanol extract of the stems of Ephedra sinica. The structures of these new compounds were elucidated on the basis of extensive spectroscopic examination, mainly including multiple 1D and 2D NMR and HRESIMS examinations, and qualitative chemical tests. All N,N-bissubstituted acetamide glycosides were found to show the obvious rotamerism, as in the case of the isolated known N-methyl-N-(4-hydroxyphenethyl)-acetamide, under the experimental NMR conditions, with the ratios of integrated intensities between anti- and syn-rotamers always being found to be about 4 to 3.Five new N-mono-/N,N-bis-substituted acetamide glycosides were isolated from the stems of Ephedra sinica. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses.

•Twenty five 13-substituted quaternary coptisine derivatives were synthesized.•Introduction of alkyls into 13-position led to significant increases of cytotoxicity.•Extending the alkyl side chain increased the cytotoxic activity.•Aromaric methyl and analogs of arylmethyls causes cytotoxicity on IEC-6.•Introducing other arylmethyls into 13-position showed no effect on tested activity.Twenty five 13-substituted quaternary coptisine derivatives were synthesized to test their cytotoxicities against several cancer cell-lines and on intestinal epithelial cell-6 (IEC-6) in vitro to evaluate structure–activity relationship (SAR). Introduction of the alkyl groups into the C-13 position of quaternary coptisine (1) led to significant increase of the cytotoxic activity, while the substitution of arylmethyl groups and others at the same position showed no effect on improving cytotoxicities against the same cancer cell-lines. The cytotoxicities of quaternary 13-alkylcoptisines was significantly reinforced as the length of the aliphatic chain increased, with quaternary 13-n-undecylcoptisine (4l) showing 7, 23, 12, and 9 times, respectively, more active than quaternary coptisine (1) against HCT, A549, Bel7402, and C33A, and being 4, 11, 2, and 3 times, respectively, more active than the positive control, fluorouracil (5-FU), against the same cell-lines, by IC50 values. In comparison to quaternary 13-n-undecylcoptisine (4l) and the above references, quaternary 13-n-dodecylcoptisine (4m) almost showed the same cytotoxicities. In contrast with the n-alkyl chains, the arylmethyl substituents at C-13 displayed low cytotoxicity, except for naphthyl rings or phenyl rings with CF3 or methyl substituents. However, their low cytotoxicity could make them useful as drug candidates for other diseases (bowel, etc).Twenty five 13-substituted quaternary coptisine derivatives were synthesized and tested for their cytotoxicity to evaluate the structure–activity relationships, with explicit influencing factor on improving activity being obtained.

The original determination of plant-derived subjects in traditional herbal medicines is often complicated by the lack of morphological features in visual or microscopic inspection. Improved methods are urgently needed. In this paper, the proton nuclear magnetic resonance (1H NMR) and high performance liquid chromatography (HPLC) profiles of fractionated polar extracts from samples of Bupleurum chinense were recorded and analyzed by comparing them to each other and to those of the isolated compounds. The 1H NMR spectra revealed distinct common features among collected samples of B. chinense, with the characteristic signals of their major constituents, saikosaponins, being exhibited explicitly and reproducibly. These features were further confirmed by HPLC and online HPLC/MS (mass spectrometry) analysis. Also, thirty-five compounds, including twenty-seven saikosaponins and eight others, were isolated from the extracts of the roots of B. chinense. On the basis of chemical investigation, the signals and peaks in the fingerprints were unambiguously assigned to their corresponding compounds. The general features of 1H NMR spectra coupled with HPLC profiles established for authentic samples of B. chinense gave specific data for those particular compounds and can be used for original authentication.

Five dihydrobenzophenanthridine alkaloids, named as maclekarpine A–E, were isolated from the roots of Macleaya microcarpa, together with 10 known benzophenanthridine/dihydrobenzophenanthridine derivatives and a known amide. Their structures were determined on the basis of spectroscopic methods. The relative configuration of maclekarpine A was solved by X-ray single-crystal diffraction, which also contributed to the establishment of the relative configuration of maclekarpine B and C, as well as the assignment of the absolute configuration of maclekarpine A–C with aid of their CD curves. Cytotoxicity of the isolated compounds against five human tumor cell-lines was evaluated, with some having activity with IC50 values ranging from 0.1 to 3.5 μM.Dihydrobenzophenanthridine alkaloids (1–5), together with 11 related compounds, were isolated from Macleaya microcarpa. Cytotoxicity of these compounds against five human tumor cell-lines was evaluated.

Chemical investigation of the roots of Nannoglottis ravida resulted in the characterization of two 5α,10α-cis-clerodane-type diterpenoides, ravidin A and B. Their structures and stereochemistry were established by spectroscopic methods, including X-ray crystallographic diffraction analysis of ravidin A. Their significance in terms of the chemotaxonomy of Nannoglottis is discussed.Clerodane-type diterpenoides, ravidin A and B, were isolated from the roots of Nannoglottis ravida, and their chemotaxonomical significance is discussed.

Nine new steroidal glycosides, named as stauntosides C–K (2, 5, 7–10, 13, 14, and 16), along with seven known compounds (1, 3, 4, 6, 11, 12, and 15) were isolated from the 95% ethanol extract of the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses, mainly 1D and 2D NMR, and HRESI-MS, and qualitative chemical methods. Their significance in terms of the chemotaxonomy of C. stauntonii is discussed.Graphical abstractNine new steroidal glycosides were isolated from the roots of Cynanchum stauntonii. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses and chemical methods.Download full-size imageHighlights► More information about the chemical constituents of Cynanchum stauntonii were given. ►·Sixteen compounds were identified, including nine new steroidal glycosides. ►·Two new 14,15-secopregnane-type skeleton aglycones were reported for the first time. ► Several new oligosaccharide chains were found for the first time.

•More information about the chemical constituents of Celastrus angulatus were given.•Four new sesquiterpene polyol esters were discovered from Celastrus angulatus.•The new sesquiterpene polyol esters were identified as β-dihydroagarofuran sesquiterpene.Celastrus species, such as Celastrus angulatus, has been demonstrated to be very rich in natural sesquiterpene polyol esters sharing the β-dihydroagarofuran skeleton, some of which showed various biological activities. In this paper, four new sesquiterpene polyol esters, named as angulatins K-N (1–4), along with three known ones, 1β-acetoxy-9β-benzoxy-4α, 6α-dihydroxy-8α, 15-diisobutanoyloxy-2β-(α-methyl)-butanoyloxy-β-dihydroagarofuran, angulatin A, and celangulin III, were isolated from the root bark of C. angulatus. The structures of the new compounds were elucidated by extensive spectroscopic methods, mainly including HR-MS and 1D and 2D NMR techniques.Four new sesquiterpene polyol esters with β-dihydroagarofuran skeleton were isolated from the root bark of Celastrus angulatus. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses.Download full-size image

The original determination of plant-derived subjects in traditional herbal medicines is often complicated by the lack of morphological features in visual or microscopic inspection. Improved methods are urgently needed. In this paper, the proton nuclear magnetic resonance (1H NMR) and high performance liquid chromatography (HPLC) profiles of fractionated polar extracts from samples of Bupleurum chinense were recorded and analyzed by comparing them to each other and to those of the isolated compounds. The 1H NMR spectra revealed distinct common features among collected samples of B. chinense, with the characteristic signals of their major constituents, saikosaponins, being exhibited explicitly and reproducibly. These features were further confirmed by HPLC and online HPLC/MS (mass spectrometry) analysis. Also, thirty-five compounds, including twenty-seven saikosaponins and eight others, were isolated from the extracts of the roots of B. chinense. On the basis of chemical investigation, the signals and peaks in the fingerprints were unambiguously assigned to their corresponding compounds. The general features of 1H NMR spectra coupled with HPLC profiles established for authentic samples of B. chinense gave specific data for those particular compounds and can be used for original authentication.