Protoxylocarpins F−H, Protolimonoids from Seed Kernels of <i>Xylocarpus granatum</i>

Three new protolimonoids, protoxylocarpins F−H (<b>1</b>−<b>3</b>), along with 11 known limonoids, were isolated from seed kernels of <i>Xylocarpus granatum</i>. Their structures were elucidated on the basis of extensive spectroscopic data analyses. All compounds isolated were evaluated for cytotoxic activity against five human tumor cell lines.