2,6-CYCLOLYCOPENE-1,5-DIOL - TOTAL SYNTHESIS OF A NATURALLY-OCCURRINGOXIDATION-PRODUCT OF LYCOPENE

2,6-Cyclolycopene-1,5-diol (3) was synthesized in 9 steps starting fro m alpha-terpinyl acetate (11). This represents the first total synthes is of an oxidative metabolite of lycopene (2). The synthesis was perfo rmed according to a C-15 + C-10 + C-15 = C-40 strategy using the Witti g olefination to couple the end groups to the central building block. An intramolecular aldol addition was used to introduce two new stereoc enters with a defined relative stereochemistry. (C) 1998 Elsevier Scie nce Ltd. All rights reserved.