Monoterpenoid indole alkaloids from Gardneria multiflora.

Six new monoterpenoid indole alkaloids, 19(E)-9-demethoxy-16-dehydroxylchitosenine-17-O- ß-d-glucopyranoside (1), 19(E)-9,10-didemethoxy-16-dehydroxylchitosenine-17-O-ß-d-gluco-pyranoside (2), 19(E)-9,10-didemethoxy-16-dehydroxyl-11-methoxychitosenine (3), 19(E)-9,10-didemethoxy-16-dehydroxyl-11-methoxychitosenine-17-O-ß-d-glucopyranoside (4), 19(Z)-18-carboxylgardneramine (5), and 19(E)-18-demethoxygardneramine-N (4)-oxide (6), along with four known alkaloids, were isolated from Gardneria multiflora, and their structures were elucidated by spectroscopic analysis. Compounds 1, 2 and 4 are the first example of Gardneria alkaloids whose glucose units were attached to C-17. None of the compounds were cytotoxic to any of five human cancer cell lines.

Chromanopyrones and a flavone from Hypericum monogynum.

Six new compounds, including three pyrone derivatives (2-4), one new flavone (5), and two new naturally-occurring compounds (1 and 6), together with 16 known compounds were isolated from the leaves and twigs of Hypericum monogynum. In addition, compounds 2-4 are racemates. Their structures and absolute configurations were determined on the basis of extensive analysis of spectroscopic data and ECD calculation. All compounds were evaluated for the inhibitory effects on α-glucosidase, compounds 1, 5, and 7 showed moderate inhibitory activities with IC50 values of 161.46, 257.78, and 11.54µg/ml, respectively. Compound 8 exhibited weak anti-oxidant activity with IC50 value of 12.55µg/ml.