Total Synthesis of (±)-Deoxypenostatin A. Approaches to the Syntheses of Penostatins A and B
作者:Barry B. Snider、Tao Liu
DOI:10.1021/jo000850x
日期:2000.12.1
A short synthesis of (+/-)-deoxypenostatin A (28) has been carried out using the convergent coupling of dienal 11, epoxide 13, and methylenetriphenylphosphorane (17) to prepare trienol 19 in only two steps. The key step is the Yb(OTf)(3)-catalyzed intramolecular Diels-Alder reaction of hydrated trienyl glyoxylate 23, which gives lactone 24 stereoselectively. Elaboration of lactone 24 to enone 27 by