Swietenialides, novel ring D opened phragmalin limonoid orthoesters from Swietenia mahogani JACQ

Three novel ring D opened limonoids corresponding to the phragmalin 8,9,14-orthoacetate with the addition of methyl 2,30-orthoacetate or a propionate, swietenialides A, B, and C and two ring-D opened phragmalin-type 1,8,9-orthoacetates, swietenialides D and E, were isolated together with one known mexicanolide, 2-hydroxyswietenin, from the ether extract of the stem bark of Swietenia mahogani JACQ. (Meliaceae). The structure of these unique compounds was elucidated by spectroscopic means.