(+)-14β-Hydroxylabda-8(17),12-dieno-16,15-lactone [(+)-Isocoronarin-D]: a New Diterpene From Hedychium coronarium (Zingiberaceae)

An investigation of the rhizome of Hedychium coronarium ( Zingiberaceae ), collected in the Kathmandu Valley, Nepal, has yielded coronarin -D, coronarin -D ethyl ether, coronarin -E, and a new diterpene identified as (+)-14ß-hydroxylabda-8(17),12-dieno-16,15-lactone, assigned the trivial name of isocoronarin-D. The structure of isocoronarin-D (3) was determined by spectroscopic and X-ray crystallographic studies.