P (OMe) ZOHC w OB z I 5 lseqment A) 6 (segment B) reaction, because the asymmetric center at C13 was expected to control the approach of the dienophile from a single diastereomeric face by steric and stereoelectronic interactions.'(3) Wadsworth-Emmons coupling of the optically active segments A (5) and B (6) was envisioned for the expeditious preparation of the requisite (E, E, E)-trienone 4.(4) Development of an asymmetric ...
