Cyclooxygenase-2 Inhibitory Compounds from the Leaves of Glycosmis pentaphylla (Retz.) A. DC.: Chemical and in silico Studies

Abstract

Glycosmis pentaphylla is traditionally used for treating many diseases in Bangladesh. Anti-inflammatory and analgesic effects of Glycosmis pentaphylla have been reported prominently but no bioactive element has been identified so far. In order to explore its analgesic and antiinflammatory compound(s), phytochemical analysis was conducted. Nine compounds were isolated from the methanol extract of leaves of Glycosmis pentaphylla whose structures were solved as arborinine (1), vanillic acid (2), 3-hydroxy-4-methoxybenzoic acid (3), benzoic acid (4), p-hydroxybenzoic acid (5), stigmasterol (6), β-amyrin (7), phytol (8) and 3α,16α-dihydroxyolean-12-ene (9) by spectroscopic studies, including high field 1H NMR analyses as well as co-TLC with authentic samples whenever possible. Among these, compounds 3 and 9 are the first report of their occurrence from G. pentaphylla. in silico docking studies of these metabolites with cyclooxygenase (COX)-2, an enzyme responsible for producing prostaglandins, were conducted. It was found that only arborinine and phytol can bind in the active site of COX-2, which might be considered as the major responsible moieties to cause analgesic and anti-inflammatory activities.