Chemical constituents of stems and branches of Adina polycephala

Abstract

To investigate chemical constituents of the stems and branches of Adina polycephala and their pharmacological activities. The constituents were isolated by a combination of various chromatographic techniques including column chromatography on silica gel, Sephadex LH-20, and C-18, as well as reversed-phase HPLC. Structures of the isolates were identified by spectroscopic data analysis. In vitro cytotoxic, anti-inflammatory, anti-oxidant, anti-HIV, neuroprotective and anti-diabetic activities were screened by using cell-based models. Twenty-eight constituents were isolated. Their structures were identified as clemochinenoside B (1), kelampayoside A (2), osmanthuside H (3), 4-hydroxy-3-methoxyphenol-beta-D-[6-O-(4-hydroxy-3,5-dimethoxylbenzoate)]-glucopyranoside (4), and syringic acid beta-D-glucopyranosyl ester (5). Ten iridoidal glycosides: geniposidic acid (6), geniposide (7), 6beta-hydroxygeniposide (8), 6beta-hydroxygeniposide (9), ixoside (10), ixoside 11-methyl ester (11), 11-methyl forsythide (12), 7beta-hydroxysplendoside (13), gardoside (14) and mussaenosidic acid (15), (+) -pinoresinol (16), (+) -medioresinol (17), (+) -syringaresinol (18), (-)-lariciresinol (19), evofolin-B (20), alpha-hydroxyacetovaillone (21), syringic acid (22), vanillin (23), 3, 4, 5-trimethoxyphenol (24), and 2,6-dimethoxy-1, 4-benzoquinone (25), beta-sitosterol (26), mannitol (27), and daucosterol (28). At a concentration of 1.0 x 10(-5) mol x L(-1), these compounds were inactive in the assays, including cytotoxicity against human tumor cell lines (HCT-8, Bel-7402, BGC-823, A549 and A2780), anti-inflammatory activity against the release of beta-glucuronidase in rat polymorphonuclear leukocytes (PMNs) induced by platelet-activating factor (PAF), antioxidant activity in Fe(2+)-cystine-induced rat liver microsomal lipid peroxidation, anti-HIV activity against HIV-1 replication, neuroprotective activity against serum deprivation or glutamate induced neurotoxicity in cultures of PC12 cells, and the inhibitory activity against protein tyrosine phosphatase 1B (PTP1B). Compounds 1-20 were obtained from the genus Adina for the first time. The 13C-NMR data of compounds 10 and 11 were reassigned. A further evaluation of pharmacological activity of these compounds is expected.