7 beta-Oxygenated limonoids from Trichilia elegans ssp elegans

Five 7 beta- and 7 alpha -oxygenated obacunone-type limonoids were obtained on reinvestigation of the seeds of Trichilia elegans ssp. elegans: 7-deoxo -7 beta -acetoxykihadanins A and B, 7-deoxo-7 beta -hydroxykihadanins A and B and 7-deoxo-7 alpha -hydroxykihadanin A, the last three being isolated a fter acetylation procedures as their mono- and/or diacetate derivatives. Th is is the first report of the natural occurrence of C-7 beta -substituted l imonoids without any oxygenated function at C-6. The structures of these co mpounds have been established on the basis of 1D- and 2D-NMR spectral techn iques, ESI-mass spectrum and X-ray crystallographic data. (C) 2000 Elsevier Science Ltd. All rights reserved.