A convenient enzymatic preparation of specifically‐labelled geraniol

Abstract

Geraniol was formed in high (up to 36%) yield when equimolar quantities of isopentenyl and 3,3-dimethylallyl pyrophosphates (1 mmole) together with inhibitors of the isomerase that interconverts them were incubated with a strictly defined cell-free extract from flowerheads of Rosa diZecta cv. Lady Seaton. essentially (>98%) complete position specificity. A simple route is thus available, given the appropriately labelled C5 precursors, for the preparation of geraniol and thence by standard chemical routes of its isomers nerol and linalool and their pyrophosphates with any chosen carbon atom specifically labelled at isotope abundances suitable for biosynthetic studies. Similarly, any desired 2H or 3H labelled geraniol or its relatives could in principle be prepared with both regio-and stereo-specificity.The C5 units were incorporated in toto with

Monoterpenoids

“…"~ The diols (158) and (159) have been synthesized and resolved and their absolute configurations have been established. 265 The isopulegols (160) have been converted266 into the a-methylene lactones (161), and the hydroxyacid (162) has served as starting material in a of the a-methylene lactam (I 63).…”