Diterpenes Derived from Clerodane Skeleton from Some Compo sitae Plants

Department of Chemistry, University of Rajasthan Jaipur-302 004

Manuscript received 18 June 1998

The structures of the clerodane derivatives solidagonal acid, a diterpene with new carbon skeleton, a hydroperoxyclerodane (3β hydroperoxy-4,18-dehydro-3,4-dihydrokolavenic acid), 2-oxo-kolavenic acid lactone, 2 α-acetoxyhardwickiic acid, 10-epi-nidoresedic acid, 16-oxo-15,16H-hardwickiic acid, 15-methoxy-16-oxo-15,16H-hardwickiic acid, 15-methoxy-16-oxo-nidoresedic acid, nor-hardwickiic acid, 15-methoxy-16-oxo-15,16H-strictic acid, nor-strictic acid, 15-desmethoxy-16-oxo-15,16H-strictic acid, 15-oxo-14,16H-strictic acid, 16-oxo-14,15-epoxystrictic acid alongwith several known diterpenes, isolated from the Indian Compositae plants Solidago altissima, Grangea maderaspatana and Pulicaria angustifolia, have been deduced mainly from high field ¹H nmr, high resolution mass spectrom­etry and noe difference spectroscopy.