Chemical studies of the Proteaceae. IV. The structures of the major phenols of Grevillea striata; a group of novel cyclophanes

Abstract

Attempts to separate the major constituents of the phenolic fraction of the ether extract of the wood of Grevillea striata R.Br. were unsuccessful, but by chemical degradation and spectroscopic methods the structures of four of the components were deduced. They were mono- and di-methyl ethers of 17,19,22,24- tetrahydroxy(l4-p-0-o)cyclophane with a double bond at either of two positions in the aliphatic chain. The new ring system was given the trivial name "turriane". Evidence that a fifth and a sixth component were derivatives with a saturated chain, and a seventh was a derivative of a double homologue of turriane, was obtained. Synthetic experiments connected with the structure determination, and on the synthesis of tetrahydroxyturriane are described. Possible biogenetic routes to striatol and the cyclophanes are discussed.