Comtrifosides A and B, two new triterpenoid saponins from the leaves of Combretum trifoliatum.

The phytochemical composition of the Combretum trifoliatum leaves was studied for the first time. Two new triterpenoid saponins, named comtrifoside A (1) and comtrifoside B (2), together with two other saponins (3-4) were purified by variously chromatographic techniques. For the first time, compound 3 was informed from the Combretum genus, as well as all of the isolated compounds (1-4) were reported from C. trifoliatum. The chemical structures of them were clearly characterised using extensive UV-VIS, IR, HRMS-ESI, and NMR experimental data. The in vitro anti-inflammatory activities of 1 & 2 were examined against NO overproduction in LPS activation of RAW264.7.

Macrotricolorin A, a new diarylpropanoid from the Vietnamese plant Macrosolen tricolor (Lecomte) Danser.

From the Vietnamese plant Macrosolen tricolor (Lecomte) Danser, one new diarylpropanoid, named macrotricolorin A (1) together with three diarylheptanoids including bisdemethoxycurcumin (2), demethoxycurcumin (3) and curcumin (4), were isolated. Their structures were elucidated by intensive analyses of their IR, UV, HR-ESI-MS and NMR (1 D & 2 D) spectra. It is the first time that diarylalkanoids have been reported from the genus Macrosolen. Compound 1 exhibited anti-inflammatory activity against the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 with an IC50 value of 27.54 ± 1.75 µM.

Cycloartane-type triterpenoids from the whole plants of Macrosolen bidoupensis.

One new cycloartane-type triterpenoid, named macrobidoupoic acid A (as an C-24 epimeric mixture, 4a, 4 b), together with three known ones (1-3), were clarified by different chromatography from the M. bidoupensis whole plants. Triterpenoids (1, 3 & 4) were detected for the first time from the Macrosolen genus. Chemical structures of them were illuminated using HR-ESI-MS, and NMR (1 D & 2 D) assessments. The cytotoxic properties of triterpenoids (3 & 4) were examined against two human cancer cell lines (A549, and RD) by MTT assay. As results shown, triterpenoids (3 & 4) possessed moderate cytotoxic activity against A549 and RD cancer cells (IC50 ranged from 5.44 to 39.52 µM).

Markhasphingolipid A, new phytosphingolipid from the leaves of Markhamia stipulata var. canaense V.S. Dang.

From the leaves of Markhamia stipulata var. canaense V.S. Dang, one new phytosphingolipid, named markhasphingolipid A (6) together with five known compounds, 4',7-O-dimethylapigenin (1), narigenin (2), tectoquinone (3), mollic acid (4), 1-hexadecanoyl-sn-glycerol (5) were classified by various chromatographic methods. Their structures were designated by IR, UV, HR-ESI-MS, HR-ESI-MS/MS and NMR experiments. All compounds were recognized for the first time from this species. The cytotoxicity of all n-hexane fractions and isolated compounds (5 & 6) against three human cancer cell lines (HeLa, HepG2, and MCF-7) were evaluated by SRB assay. All n-hexane fractions expressed cytotoxic effect on three tested cancer cell lines (at the concentration of 100 µg/mL, percent of cytotoxicity ranged from 55.81% to 95.83%) as well as compound 5 (IC50 ranged from 48.51 to 63.30 µM) whereas fraction H.I and compound 6 did not show activity.[Formula: see text].

Markhacanasin C, cycloartane triterpenoid from the leaves of Markhamia stipulata var. canaense V.S. Dang.

One new cycloartane triterpenoid, named markhacanasin C (1), together with three known triterpenoids, oleanolic acid (2), ursolic acid (3) and 6ß,19α-dihydroxyursolic acid (4) were isolated by various chromatographic methods from the most cytotoxic fraction of the ethyl acetate extract of Markhamia stipulata var. canaense V.S. Dang leaves. Among them, 4 was reported for the first time from the genus Markhamia, while 2 and 3 were found for the first time from this species. Their structures were elucidated by IR, UV, HR-ESI-MS and NMR experiments. The cytotoxicity of isolated compounds (3 and 4) against three human cancer cell lines (HeLa, HepG2, and MCF-7) were evaluated. At the concentration of 100 µg/mL, 3 exhibited significant cytotoxic activity (86.36 ± 3.69%).

Triterpene saponins with α-glucosidase inhibition and cytotoxic activity from the leaves of Schefflera sessiliflora.

From the leaves of Schefflera sessiliflora De P. V., two new triterpene saponins including one oleanane-type saponin, named scheffleraside C (1) and one lupane-type saponin scheffleraside D (2), together with six known triterpene saponins (3-8), were isolated by various chromatography methods. Among them, 3 was found for the first time from natural sources, while 6-8 were isolated for the first time from the genus Schefflera. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments, and comparison of their NMR data with previously reported data. Their α-glucosidase inhibition and cytotoxic activity against MCF-7 human breast cancer cell lines were evaluated. The isolates (1, 3-5, 8) showed stronger α-glucosidase inhibitory activity (IC50 = 5.99-76.58 µM) than the standard drug acarbose (IC50 = 214.50 µM). At the concentration of 100 µg/ml, the isolates (1, 2) showed appreciable cytotoxic activity (67.92, 63.83%, respectively).

New C20-gibberellin diterpene from the leaves of Schefflera sessiliflora De P. V.

From the leaves of Schefflera sessiliflora De P. V., one new C20-gibberellin diterpene 2ß,12ß-dihydroxygibberellin (12ß-hydroxy-GA110 or 2ß-hydroxy-GA112) (1), together with three known compounds, trans-tiliroside (2), kaempferol 3-O-ß-D-glucuronopyranoside (3), 5-p-trans-coumaroylquinic acid (4), was isolated for the first time from the genus Schefflera by various chromatography methods. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolates (2, 3) showed better α-glucosidase inhibitory activity (IC50 = 134.60, 147.10 µM, respectively) than the standard drug acarbose (IC50 = 214.50 µM).