REASSIGNMENT OF CONFIGURATION TO 22-HYDROXYCHOLESTEROLS . SYNTHESIS OF (22S)- AND (22R)-3H-CHOLESTEROLS

Stereospecifically labeled (22S)- and (22R)-3H-cholesterols were synthesized via (22S)-hydroxy-22-3H- and (22R)-hydroxy-22-3H-cholesteryl 3-benzoates, respectively. The (22S)- and (22R)-hydroxycholesterols, the (22S)- and (22R)-hydroxycholesteryl 3-benzoates and the (22S)- and (22R)-hydroxycholesteryl 3-methyl ethers were interrelated. Assignments of configuration at C-22 were made on the basis of the Horeau and Prelog procedures; the two methods lead to identical assignments. Our results demonstrate that the configurations assigned previously to the 22-hydroxycholesterols and their derivatives are incorrect and should be reversed. © 1969, American Chemical Society. All rights reserved.