Facile and Practical Total Syntheses of (±)-Mukulol and (±)-Cembrene by Low-valent Titanium-induced Keto Ester Cyclization
作者:Weidong Li、Ying Li、Yulin Li
DOI:10.1246/cl.1994.741
日期:1994.4
A direct approach of low-valent titanium-induced intramolecular keto ester cyclization was first applied to the total syntheses of macrocyclic diterpenoids, by which (±)-mukulol and (±)-cembrene were synthesized from geranylacetone by a short and efficient route.
Structures of two new diterpenoids, cembrene-A and mukulol are reported. Cembrene-A is one of the two most elementary tetraenes derivable from geranyl-geranyl pyrophosphate by C1 → C14 cyclization. Mukulol is also a cembrane derivative and is biogenetically closely related to cembrene-A.