A comparative crystallographic analysis of the X-ray structure of three cholest-based steroidal molecules

The molecular and crystal structures of (+)-4-cholesten-3-one 1 cholesteryl chloroformate 2 and cholesteryl-caprylate 3 have been determined by using X-ray crystallographic and computational techniques. All the three compounds crystallize in the monoclinic space group P2 1 with unit cell parameters: a=10.683(5)A, b=7.861(2), c=14.616(2), P=105.8(2)° for |1], a=12.294(2)A, b=9.399(8), c=12.787(2), β=113.3(1)° for [2] and a = 12.778(9), b = 9.201(4), c = 14.063(6) A, β = 93.85(4)° for [3]. The number of molecules per unit cell in case of each structure is 2. The final R-factor for [1] is 0.054, [2] 0.077 and [3] 0.068. Besides some interesting geometrical and structural features, all the three molecules exhibit C-H...O hydrogen bonding. A comparative crystallographic analysis of all the three molecules has been reported in this paper.