A comparative structural study of the steroid epimers: 17β-amino-1,3,5(10)- estratrien-3-ol, 17α-amino-1,3,5(10)-estratrien-3-ol, and some derivatives by 1H NMR, and x-ray diffraction analysis

The epimers 17β-amino-1,3,5(10)-estratrien-3-ol and 17α-amino-1,3,5(10)-estratrien-3-ol were synthesized. 17β-Amino-1,3,5(10)-estratrien-3-ol was prepared by catalytic hydrogenation of the estrone–oxime. The 17α-amino epimer was obtained from estradiol, via tosylate, followed by nucleophilic displacement by sodium azide and subsequent reduction with LiAlH 4. They were characterized by spectroscopic methods. Determination of the crystal structures of 3-(toluene-4-sulfonyloxy)-17α-azido-1,3,5(10)-estratriene, 3-(toluene-4-sulfonyloxy)-17-α-amino-1,3,5(10)-estratriene hydrochloride, 17β-acetylamino-1,3,5(10)-estratriene-3-ol, and 3-acetoxy-17β-acetylamino-1,3,5(10)-estratriene enabled us to characterize the structure of the 17α and 17β amino epimers for the first time.