Granatumins A−G, Limonoids from the Seeds of a Krishna Mangrove, <i>Xylocarpus granatum</i>

Seven new limonoids (<b>1</b>−<b>7</b>), named granatumins A−G, were isolated from seeds of an Indian mangrove (<i>Xylocarpus granatum</i>) collected from the wetlands of Krishna estuary, Andhra Pradesh. The known compounds khayasin T, tigloylseneganolide A, 6-deoxyswietenine, swietemahonolide, febrifugin A, gedunin, xylogranatinin, phaseic acid, (2<i>R</i>,3<i>R</i>)-3,4′,5,7-tetrahydroxyflavanone, and (<i>E</i>)-4-hydroxycinnamic acid were also isolated. The structures were established on the basis of spectroscopic data. Granatumins A and B are mexicanolides with <i>endo</i>-conjugated Δ<sup>8,30</sup> and Δ<sup>14,15</sup> double bonds, and granatumins F and G are polyhydroxylated phragmalins found previously in plants of the Meliaceae. Khayasin T exhibited moderate insecticidal activity against fifth instar larvae of <i>Brontispa longissima</i> (Gestro) at a concentration of 20 mg/L.