Undescribed Triterpenes from the Leaves of Syzygium myrsinifolium with Their α-Glucosidase and α-Amylase Inhibition Activity.

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.

Three Undescribed Iridoid Derivatives Isolated from the Fruits of Vitex trifolia with Their Cytotoxic and Antimicrobial Activities.

Vitex trifolia L. is a medicinal plant and widely distributed in the northern mountainous areas of Vietnam. Phytochemical study on the fruits of this plant led to the isolation of nine iridoid derivatives (1-9) including three undescribed compounds (1-3). Their structures were elucidated to be 3''-hydroxyscrophuloside A1 (1), 3''-hydroxycallicoside D (2), 2'-p-hydroxybenzoylaucubin (3), 6'-p-hydroxybenzoylmussaenosidic acid (4), nishindaside (5), agnuside (6), 10-O-vanilloylaucubin (7), 6'-O-p-hydroxybenzoyl-gardoside (8), and buddlejoside B (9) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1, 2, 4, and 8 significantly posessed anti-barterial activity against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa strains with MIC values in range of 16-64 µg/mL. At concentration of 20 µM, compounds 1-9 did not show cytotoxic effects against human lung cancer cells (PC9).

One new furostane saponin from Allium ramosum and lipid accumulation inhibitory activity.

A new furostane saponin, ramosaponin (1), and four known furostane saponins, protodioscin (2), dehydrotomatoside (3), (25 R)-26-O-(ß-D-glucopyranosyl)-furost-5-ene-3ß,22α,26-triol 3-O-ß-D-glucopyranosyl-(1→4)-ß-D-galactopyranoside (4), and anguivioside A (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell line. As a result, compound 1 showed significant lipid accumulation inhibitory activity with an IC50 value of 64.32 ± 3.87 µM.

Furostane Saponins from the Seeds of Allium ramosum and Their Lipid Accumulation Inhibitory Activity.

Three new furostane saponins, ramofurosides A-C (1-3), and two known saponins, fistulosaponin B (4) and (25R)-26-O-ß-D-glucopyranosyl-1ß,3ß,26-trihydroxyfurosta-5,20(22)-diene-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell lines. As a result, compounds 1 and 3 showed a significant reduction in total lipid content by 27.93±3.05 and 27.54±1.68 %, respectively, at a concentration of 100 µM.

Dihydrostilbene glycosides from Camellia sinensis var. assamica and their cytotoxic activity.

Three undescribed dihydrostilbene glycosides, 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(4'''-hydroxylbenzoyl)]-ß-D-glucopyranoside (1), 3,5-dihydroxyldihydrostilbene 4'-O-(6''-O-galloyl)-ß-D-glucopyranoside (2), and 3,5-dihydroxyldihydrostilbene 4'-O-[6''-O-(3''',4'''-dimethoxyl)galloyl]-ß-D-glucopyranoside (3), and seven known compounds, kaempferol 3-O-ß-D-glucopyranoside (4), isoquercitrin (5), kaempferol 3-O-α-L-rhamnoside (6), quercitrin (7), (6S,9R)-roseoside (8), (-)-epicatechin 3-O-gallate (9), and (-)-epigallocatechin 3-O-gallate (10) have been isolated from the methanol extract of the leaves of Camellia sinensis var. assamica (J.W.Mast.) Kitam. (synnonym of Camellia assamica (Mast.) H.T.Chang) (Theaceae). Their structures were elucidated by spectroscopic methods (1 D-, 2 D-NMR) and mass spectra. All compounds were evaluated for cytotoxic activity against human oral cancer (CAL27) and human breast cancer (MDAMB231) cell lines. Compound 10 showed significant cytotoxic activity against CAL27 and MDAMB231 cell lines with IC50 values of 9.78 ± 0.25 and 3.27 ± 0.18 µM, respectively, compared to those of positive control, capecitabine (IC50 values of 8.20 ± 0.75 and 5.20 ± 0.89 µM).

Novel ANO1 Inhibitor from Mallotus apelta Extract Exerts Anticancer Activity through Downregulation of ANO1.

Anoctamin1 (ANO1), a calcium-activated chloride channel, is frequently overexpressed in several cancers, including human prostate cancer and oral squamous cell carcinomas. ANO1 plays a critical role in tumor growth and maintenance of these cancers. In this study, we have isolated two new compounds (1 and 2) and four known compounds (3-6) from Mallotus apelta. These compounds were evaluated for their inhibitory effects on ANO1 channel activity and their cytotoxic effects on PC-3 prostate cancer cells. Interestingly, compounds 1 and 2 significantly reduced both ANO1 channel activity and cell viability. Electrophysiological study revealed that compound 2 (Ani-D2) is a potent and selective ANO1 inhibitor, with an IC50 value of 2.64 µM. Ani-D2 had minimal effect on cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel activity and intracellular calcium signaling. Notably, Ani-D2 significantly reduced ANO1 protein expression levels and cell viability in an ANO1-dependent manner in PC-3 and oral squamous cell carcinoma CAL-27 cells. In addition, Ani-D2 strongly reduced cell migration and induced activation of caspase-3 and cleavage of PARP in PC-3 and CAL-27 cells. This study revealed that a novel ANO1 inhibitor, Ani-D2, has therapeutic potential for the treatment of several cancers that overexpress ANO1, such as prostate cancer and oral squamous cell carcinoma.

Enantiomeric chromene derivatives with anticancer effects from Mallotus apelta.

Mallotusapelta(Lour.) Müll.Arg has been used in traditional medicine for the treatment of chronic hepatitis. Six new chromene derivatives, malloapeltas C-H (1-6) and one known compound, malloapelta B (7) were isolated and structured from the leaves of M.apelta. Two pairs of enantiomers (1a/1b and 2a/2b) were successfully separated by chiral high-pressure liquid chromatography (HPLC). The structures and absolute configurations of compounds were determined using spectroscopic methods, including 1D, 2D NMR, and MS and quantum chemical calculation methods. All compounds were evaluated for cytotoxic activity using cell counting kit-8 (CCK-8) assay against ovariancancer cell line (TOV-21G). Compounds 1-5 and 7 exhibited significant growth and viability inhibitory effects with GI50 values ranging from 0.06 to 10.39 µM and IC50 values ranging from 1.62 to 10.42 µM on ovarian cancer cell line, TOV-21G. The most cytotoxic compounds 2, 3, and 7 were chosen for studying in apoptosis mechanism. Compounds 2, 3, and 7-induced apoptosis as evidenced by activated caspase 8, caspase 9, and PARP, increased Bak and Bax, and decreased Bcl-xL and survivin. Moreover, compounds 2, 3, and 7 significantly inhibited the NF-κB signaling pathway. Taken together, our findings propose the potential application of compounds 2, 3, and 7 for treating cancer via modulating NF-κB activity.

Five New Pregnane Glycosides from Gymnema sylvestre and Their α-Glucosidase and α-Amylase Inhibitory Activities.

Gymnema sylvestre, a medicinal plant, has been used in Indian ayurvedic traditional medicine for the treatment of diabetes. Phytochemical investigation of Gymnema sylvestre led to the isolation of five new pregnane glycosides, gymsylosides A-E (1-5) and four known oleanane saponins, 3ß-O-ß-D-glucopyranosyl (1→6)-ß-D-glucopyranosyl oleanolic acid 28-O-ß-D-glucopyranosyl ester (6), gymnemoside-W1 (7), 3ß-O-ß-D-xylopyranosyl-(1→6)-ß-D- glucopyranosyl-(1→6)-ß-D-glucopyranosyl oleanolic acid 28-O-ß-D-glucopyranosyl ester (8), and alternoside XIX (9). Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for their α-glucosidase and α-amylase inhibitory activities. Compounds 2-4 showed significant α-amylase inhibitory activity, with IC50 values ranging from 113.0 to 176.2 µM.

Chemical constituents of the Annona glabra fruit and their cytotoxic activity.

CONTEXT: Traditional Chinese medicines have attracted increasing interest as potential sources of novel drugs with a wide range of biological and pharmacological activities. Annona glabra Linn (Annonaceae) is used in traditional medicine as an anticancer drug. Phytochemical investigation of this plant led to the isolation of acetogenins, ent-kauranes, peptides, and alkaloids. In addition, compounds exhibited anticancer, anti-HIV-reserve, and antimalaria. OBJECTIVE: Isolation, structure determination, and cytotoxic activity evaluation of compounds from the methanol extract from A. glabra fruits. MATERIALS AND METHODS: Using chromatographic methods to isolate compounds from the A. glabra methanol extract. The cytotoxic activity of compounds was evaluated by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, compounds which showed significant cytotoxic activity were chosen for further study apoptosis characteristics. RESULTS: One new, (2E,4E,1'R,3'S,5'R,6'S)-dihydrophaseic acid 1,3'-di-O-ß-d-glucopyranoside, and eight known compounds, (2E,4E,1'R,3'S,5'R,6'S)-dihydrophaseic acid 3'-O-ß-d-glucopyranoside (2), icariside D2 (3), icariside D2 6'-O-ß-d-xylopyranoside (4), 3,4-dimethoxyphenyl O-ß-d-glucopyranoside (5), 3,4-dihydroxybenzoic acid (6), blumenol A (7), cucumegastigmane I (8), and icariside B1 (9), were isolated from the fruits of A. glabra. Icariside D2 (3) was found to show significant cytotoxic activity on the HL-60 cell line with the IC50 value of 9.0 ± 1.0 µM and did not show cytotoxic activity on the Hel-299 normal cell line. The further test indicated that compound 3 induced apoptosis via alteration of expression of apoptosis-related proteins and decreased phosphorylation of AKT in HL-60 cells. DISCUSSION AND CONCLUSION: The results suggested that the constituents from A. glabra may contain effective compounds which can be used as anticancer agents.

New isoflavone glycosides from the stems of Dalbergia vietnamensis.

Two new isoflavone glycosides, dalspinosin 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (1) and caviunin 7-O-(5-O-trans-p-coumaroyl)-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (2), and two known compounds, caviunin 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (3) and caviunin (4) were isolated from the stems of Dalbergia vietnamensis. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D- and 2D-NMR spectroscopy, as well as by comparing with the NMR data reported in the literature.

Cucurbitane-type triterpene glycosides from the fruits of Momordica charantia.

Four new cucurbitane-type triterpene glycosides, charantosides D-G (1-4) were isolated from a methanol extract of Momordica charantia fruits. The structures of these compounds were determined by chemical and spectroscopic methods to be (19R)-5 beta,19-epoxy-25-methoxycucurbita-6,23-diene-3 beta,19-diol 3-O-beta-D-glucopyranoside, (19R)-5 beta, 19-epoxy-25-methoxycucurbita-6,23-diene-3 beta,19-diol 3-O-beta-D-allopyranoside, 7 beta-methoxycucurbita-5,23E,25-triene-3 beta-ol 3-O-beta-D-allopyranoside, and 3 beta,7 beta-dihydroxycucurbita-5,23E,25-triene- 19-al 3-O-beta-D-allopyranoside.