Musa A.M Department of Pharmaceutical and Medicinal Chemistry, Ahmadu Bello University, Zaria-Nigeria
Abstract:
A mixture of two new dihydrostilbenes, 3-methoxy-4,5-methylenedioxy-4'-O-(2,3-dihydroxy-3-methylbutyl)-dihydrostilbene (1) and 3,5-dimethoxy-4'-O-(2,3-dihydroxy-3-methylbutyl)-dihydrostilbene (2), was isolated from Indigofera pulchra as an inseparable mixture. Several isolation strategies, including multiple preparative TLC, SPE and finally HPLC were undertaken in an attempt to separate these metabolites to no avail. Structure elucidation on the mixture was conducted and we were able to establish the structures of these compounds unambiguously by MS and a series of 1D and 2D-NMR analyses. The mixture of these dihydrostilbenes was analysed by NMR and 1 and 2 were in a ratio of 52:48 respectively and this was evaluated against a panel of methicillin-resistant Staphylococcusaureus(MRSA) and multidrug-resistant variants of this organism, including a strain over-expressing the NorA efflux pump and weak activity was observed.
