The first total synthesis of the (5R,8S,13R,16S)-isomer 3 of pyrenopho
rol is described using a retrosynthetic scheme based on two consecutiv
e double bond cleavages. The title compound 3 was prepared in 14 steps
with an overall yield of 4.5% starting from the key synthon 6, readil
y prepared from (S)-(-)-ethyl lactate. (C) 1997 Elsevier Science Ltd.