Mappianines A-E, structurally diverse monoterpenoid indole alkaloids from Mappianthus iodoides.

Five previously undescribed monoterpenoid indole alkaloids, mappianines A-E, along with twelve known analogues, were isolated from the stems of Mappianthus iodoides Hand.-Mazz. Their structures and absolute configurations were determined by spectroscopic analysis, single-crystal X-ray diffraction, and ECD calculations. The plausible biogenetic pathway of mappianine A was proposed. All the isolated compounds were evaluated for their cytotoxic effects on MGC-803, Bel-7404, A549, NCI-H460, and HepG2 cancer cell lines. Mappianine B, tetrahydroalstonine, ß-carbolin-1-one, and 1,2,3,4-tetrahydronorharman-1-one displayed moderate cytotoxicity against all cell lines tested, with IC50 values ranging from 5.19 to 42.86 µM.

Cytotoxic triterpenoid saponins from Lysimachia foenum-graecum.

Eleven oleanane-type triterpenoid saponins, foegraecumosides A-K, and eight known ones, were isolated from the aerial parts of Lysimachia foenum-graecum. Their structures were elucidated by spectroscopic data analyses and chemical methods. All isolated saponins were evaluated for their cytotoxicity against four human cancer cell lines (NCI-H460, MGC-803, HepG2, and T24). Seven saponins containing the aglycone cyclamiretin A exhibited moderate cytotoxicity against all tested human cancer cell lines, with IC50 values of 9.3-24.5 µM. Simultaneously, the cytotoxic activities of foegraecumosides A and B, lysichriside A, ardisiacrispins A and B, cyclaminorin, and 3-O-α-L-rhamnopyranosyl-(1 â†’ 2)-ß-d-glucopyranosyl-(1 â†’ 4)-α-l-arabinopyranosyl-cyclamiretin A were tested on drug-resistant lung cancer cell lines (A549 and A549/CDDP, respectively). Ardisiacrispin B displayed moderate cytotoxicity against A549/CDDP, with an IC50 value of 8.7 µM and a resistant factor (RF) of 0.9.

[Studies on chemical constituents of Clerodendrum bungei].

Ten compounds were isolated from the 95% aqueous EtOH extract of Clerodendrum bungei by a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, MCI, ODS, and semi-preparative HPLC. Their structures were elucidated as 11,12,16S-trihydroxy-7-oxo-17(15→16),18(4→3)-diabeo-abieta-3,8,11,13-tetraen-18-oic acid (1), 12S*,13R*-dihydroxy-9-oxo-octadeca-10(E)-enoic acid (2), clerodenoside A (3), trichotomoside (4), glycosmisic acid (5), 4'-O-methylscutellarein (6), neroplomacrol (7), butylitaconic acid (8), hexylitaconic acid (9), p-hydroxybenzonic acid (10) by their physicochemical properties and spectroscopic data. Compounds 1 and 2 are new natural products, while compounds 7-10 were obtained from the genus Clerodendrum for the first time, and compounds 3, 5, 6 were isolated from this plant for the first time.