Two new norlignans from the aerial parts of Pouzolzia sanguinea (Blume) Merr.

Two new norlignans, pouzolignan N (1) and pouzolignan O (2), together with five known norlignans, pouzolignan F (3), pouzolignan G (4), pouzolignan H (5), pouzolignan L (6), and gnetifolin F (7) were isolated from the aerial parts of Pouzolzia sanguinea (Blume) Merr. Their chemical structures were elucidated via HR-ESI-MS and NMR spectroscopic methods. Absolute configurations at stereocenters were confirmed by comparisons of CD spectra with those of TD-DFT calculations. Compounds 1-6 exhibited chemical structures unique to Pouzolzia species. At a concentration of 30 µM, compounds 1-7 exhibited weak cytotoxic activity toward CAL27 and MDA-MB-231 cell lines (cell viability from 65.3 ± 0.86 to 98.8 ± 1.23%). They also inhibited anoctamin-1 activity with inhibitory rates from 8.1 ± 0.87 to 24.3 ± 1.41%.

Triterpenoid glycosides from the rhizomes of Allium ascalonicum and their anoctamin-1 inhibitory activity.

Ten triterpenoid glycosides including two undescribed compounds (1 and 2) were isolated from the methanol extract of Allium ascalonicum rhizomes. These compounds were structurally elucidated to be 3ß-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-19α-hydroxyolean-12-ene-28-oic acid 28-O-[α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranosyl] ester (1), 3-O-ß-D-glucopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-α-L-arabinopyranosyl-3ß,19α-dihydroxyoleanane-12-en-28-oic acid (2), lactifoloside C (3), lactifoloside H (4), randiasaponin IV (5), kudinoside G (6), ilexkudinoside W (7), lactifoloside G (8), kudinoside D (9), and ilexkudinoside T (10) by analyzing their HR-ESI-MS, NMR spectral data and by comparison with those reported in the literature. Compounds 1-10 were evaluated for anoctamin-1 (ANO1) inhibitory activity using yellow fluorescent protein reduction assays. At the concentration of 30 µM, compounds 2 and 9 displayed moderate ANO1 inhibitory percentages of 28.9 ± 0.85% and 26.2 ± 0.65%, respectively.

Four new pregnane glycosides from Gymnema latifolium and their α-glucosidase and α-amylase inhibitory activities.

Four new pregnane glycosides, gymlatifosides A - D (1 - 4) and one known pregnane glycoside, verticilloside J (5) were isolated from the leaves of Gymnema latifolium Wall. ex Wight. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR, HR-ESI-MS, and in comparison with the reported data. All these compounds were tested for α-glucosidase and α-amylase inhibitory activities. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 37.8 ± 1.5% at the concentration of 200 µM. Compounds 1-4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 7.0 to 30.1%. In addition, all compounds 1-5 showed moderate/weak anti α-amylase activity in the investigated test.

New lupane-type and ursane-type triterpene saponins from the leaves of Trevesia palmata.

Three new triterpene saponins including two lupane-types and an ursane-type were isolated from the leaves of Trevesia palmata. Their structures were determined as 2α,3ß,23-trihydroxylup-20(29)-en-28-oic acid 3-O-α-L-arabinopyranoside (1), 2α,3ß,23-trihydroxylup-20(29)-en-28-oic acid 3-O-[α-L-arabinopyranoside]-28-O-[ß-D-glucopyranosyl] ester (2), and 2α,3ß,23-trihydroxyurs-12-en-28-oic acid 3-O-[α-L-arabinopyranoside]-28-O-[ß-D-glucopyranosyl(1→2)-ß-D-glucopyranosyl] ester (3) by analysis of their HR-ESI-MS, 1D and 2D NMR spectra. The 2α,3ß,23-trioxygenated pentacyclic triterpenes were uncommonly found in the nature. At concentration of 100 µM, compounds 1-3 inhibited NO production in LPS activated BV2 cells with inhibitory rates of 17.4 ± 1.8%, 33.1 ± 1.2%, and 11.7 ± 2.2%, respectively. But, they did not significantly inhibit yeast α-glucosidase activity.

Chemical constituents from Schisandra sphenanthera and their cytotoxic activity.

Extensive phytochemical investigation of Schisandra sphenanthera leaves resulted in the isolation of six highly oxygenated nortriterpenoids (1-6) and five lignans (7-11) including a new pre-schisanartane-type, schisandrathera A (1), a new dibenzocyclooctadiene glycoside, schisandrathera B (7) and two new lignans, schisandrathera C (8) and schisandrathera D (9). Their chemical structures including absolute configurations were determined extensively by means of HR-ESI-MS, NMR, and ECD spectra. In addition, all isolated compounds were tested for cytotoxic activity against PC3 (prostate cancer) and MCF7 (breast cancer) cell lines. Among these compounds, schirubrisin B (3) showed strong cytotoxic effect on both PC3 and MCF7 cell lines with IC50 values of 3.21 ± 0.68, 13.30 ± 0.68 µM, respectively, whereas ten remaining compounds were found to be less effective in the investigated models.

Pregnane glycosides from Gymnema inodorum and their α-glucosidase inhibitory activity.

Two new pregnane glycosides, gyminosides A and B (1 and 2) and three known, tinctoroside B (3), tinctoroside C (4), and gymnepregoside F (5) were isolated from the leaves of Gymnema inodorum (Lour.) Decne. Their structures were elucidated by physical and chemical methods and comparing with those reported in the literature. All these compounds were evaluated for α-glucosidase assay. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 63.7 ± 3.9% at the concentration of 200 µM. Compounds 1-4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 40.0 to 52.1%.

Four new sucrose diesters of substituted truxinic acids from Trigonostemon honbaensis with their anoctamin-1 inhibitory activity.

Truxinic acid sucrose diesters analogs possess interesting chemical structure by the presence of cyclobutane-ring and macrocyclic sucrose diesters moieties which are rarely found from natural sources. This paper describes the isolation and structural elucidation of four new sucrose diesters of substituted truxinic acids, trigohonbanosides A-D (1-4), from the leaves of Trigonostemon honbaensis. Their chemical structures were elucidated by HR-ESI-MS, NMR, and CD spectroscopic methods. At a concentration of 30 µM, compounds 1-4 moderately inhibited ANO-1 activity with inhibitory percentages of 27.7 ± 1.10%, 35.6 ± 0.92%, 43.7 ± 1.61%, and 40.8 ± 1.25%, respectively.