Toshie Fujishima, Tsutomu Suenaga and Takato Nozaki Pages 2446 - 2453 ( 8 )
The hormonally active form of vitamin D3, 1α,25-dihydroxyvitamin D3 (1a), has a wide variety of biological activities and its major molecular target is considered to be the vitamin D receptor (VDR). The A-ring stereoisomers of 1a as well as its C2-modified analogues, which have different stereochemistry at the C1 and/or C3 hydroxy groups, are of interest since recent metabolic studies have shown that catabolism could occur through A-ring modification. In this review, a practical and versatile synthesis of the A-ring enyne precursors by the convergent method of Trost and coworkers, which is needed to construct all possible A-ring stereoisomers of 1,25-dihydroxyvitamin D3 (1a-d), and the C2-modified analogues (4a-d, 5a-d, 6a-d and 7a-d) is described. A strategy for the synthesis and evaluation of all possible A-ring stereoisomers of 1a and their A-ring modified analogues is important, and this will stimulate synthesis and biological studies into vitamin D.
Analogue, Chemical synthesis, Hormone, Nuclear receptor, Steroid, Vitamin.
Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, Shido, Sanuki, Kagawa 769-2193, Japan.