RESUMO
A new sesquiterpene lactone, drypemolundein A and a new friedelane derivative, drypemolundein B, along with seven known compounds have been isolated from the whole stems of Drypetes molunduana Pax and Hoffm. Their structures were established on the basis of one- and two-dimensional NMR, homo- and hetero-nuclear spectroscopic evidence.
Assuntos
Lactonas/isolamento & purificação , Rosales/química , Sesquiterpenos/isolamento & purificação , Lactonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesquiterpenos/químicaRESUMO
Phytochemical studies on the stem bark of Guibourtia tessmanii yielded a dihydrochalcone glucoside, 2',4-dihydroxy-4'-methoxy-6'-O-beta-glucopyranoside dihydrochalcone and a new stilbene glycoside, 3,5-dimethoxy-4'-O-(beta-rhamnopyranosyl-(1-->6)-beta- glucopyranoside) stilbene besides the known pterostilbene. Their structures were established on the basis of one and two dimensional NMR spectroscopic techniques, FABMS and chemical evidence.
Assuntos
Chalcona/isolamento & purificação , Fabaceae/química , Fenóis/isolamento & purificação , Estilbenos/isolamento & purificação , Chalcona/análogos & derivados , Chalcona/química , Chalconas , Estrutura Molecular , Fenóis/química , Análise Espectral , Estilbenos/químicaRESUMO
Two new isoflavones, named conrauinones A (1) and B (2), have been isolated from the stem bark of Millettia conraui, in addition to known 5-methoxydurmillone. The structures of the new compounds were determined by spectroscopic analysis including 2D NMR techniques as 5,6,2'-trimethoxy-4',5'-(methylenedioxy)-2",2"-dimethylpyrano[5",6":7,8]isoflavone (1) and 6-methoxy-3',4'-(methylenedioxy)-7-O-[(E)-3",7"-dimethyl-7"-ol-2",5"-octadienyl]isoflavone (2).
RESUMO
Asebotin (1), a dihydrochalcone glucoside, was isolated from the stem bark of Guibourtia tessmanni and characterised by means of spectroscopic analysis including 1H-, 13C, MS and 1D Noe difference experiment.