Chemical and Spectral Studies on Nimbin Group of Neem (Azadirachta indica A. Juss) Constituents*
Abstract
Nimbin (1), 4-epinimbin (2) and 6-desacetylnimbin (3) were converted into nimbolide (6) and two novel pentanortriterpenoidal congeners viz. desacctylnitnbinene, (8) and nimbinene (9). The two dimensional 1H HOMCOR spectrum of 1, mass spectra of 2 and 4-epinimbic acid (5), 1H and 13C nmr spectral data of 6 and pyronimbic acid (7) are also presented.
