Synthesis of (-)-astrogorgiadiol.
Reaction of Rh2(S)-PTPA4 with the (R)-citronellol-derived alpha-diazo-beta-ketoester 1 led to the formation of cyclic beta-ketoester 2 in 95% yield and 48% diastereomeric excess. The purity of 2 was increased to > 99% de after one crystallization. To demonstrate its utility in steroid total synthesis, the beta-ketoester 2 was carried on to secosteroid (-)-astrogorgiadiol (3), a naturally occurring vitamin D analogue with antiproliferative properties.
Taber
D F
DF
Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA. taberdf@udel.edu
Malcolm
S C
SC
D002384:Catalysis; D013057:Spectrum Analysis; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000138:chemical synthesis*
C431680:astrogorgiadiol; D014807:Vitamin D