Crystal and Molecular Structure of Synthetic Cholesterol Compounds — Vitamin D3-Analogues (I) 24(S)-Hydroxy Coprastan-3-one & (II) 24(R)-Hydroxy Coprastan-3-one

Abstract The title compound I (24-(S)-Hydroxy Coprastan-3-one) crystallises in orthorhombic space group P212121 with Z=4. The unit cell dimensions are a=6.701(2)Å, b=11.506(8)Å, c=32.183(4)Å, V=2481(2)Å3, Dcal=1.077 Mg/m3. The title compound II (24-(R)-Hydroxy Coprastan-3-one) crystallises in orthorhombic space group P212121 with two molecules per assymetric unit and with Z=8. The Unit cell dimensions are a=10.954(2)Å, b=21.757(6)Å, c=21.130(7)Å, V=5035.0(2)Å3, Dcal=1.062 Mg/m3. In compound I and in both the molecules of compound II, the rings A, B & C are in chair conformation and the five membered ring D is in envelope conformation. The priority sequence attached to the chiral carbon C24 has “S” designation in compound I and “R” designation in compound II. The structures are stabilized by C-H…O and O-H—O hydrogen bonds.