RESUMO
Four new compounds (1-4) were isolated from the stem bark of Entandrophragma angolense along with eleven known structures (5-15). The chemical structures were elucidated on the basis of spectroscopic and HRMS data, and the absolute configuration was established with the aid of electronic circular dichroism. Compound 5 displayed moderate cytotoxicity against MDA-MB-231, OVCAR3, MDA-MB-435, and HT29 cell lines, with IC50 values ranging from 2.0-5.9 µM.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Limoninas/isolamento & purificação , Estrutura Molecular , Nigéria , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Casca de Planta/química , Plantas Medicinais/química , Triterpenos/isolamento & purificaçãoRESUMO
Phytochemical investigation of the leaves and bark of Psydrax subcordata has led to the isolation of six new iridoids, subcordatanols I-V (1-4 and 6) and 1-O-methylcrescentin I (5), along with two known analogues (7 and 8). Among them, subcordatanol I (1) is the first example of a 3,8-monoepoxy-iridoid featuring a caged 2-oxa-bicyclo[3.2.1]octane core. The absolute stereochemistry at C-4 of 3, 4, and 6 was established through their acid-catalyzed reaction products subcordatalactones A (3a), B (4a), and C (6a), respectively. Subcordatanols I (1) and II (2), as well as subcordatalactones A (3a) and B (4a), displayed inhibitory activity against protein tyrosine phosphatase 1B (PTP1B). Enzyme kinetic studies indicated that 3a and 4a are competitive inhibitors. A molecular docking study is also reported.
