[Chemical constituents of stems and branches of Adina polycephala]

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.