Crystal Structure and Synthesis of 3iβ/i-(ip/i-Iodobenzoyloxy)-16iα/i,17iα/i-Epoxypregn-4-En-6,20-Dione

摘要

3β-(p-iodobenzoyloxy)-16α,17α-epoxypregn-4-en-6,20-dione (7), C28H31O5I, was synthesized from the commercially available 16-dehydropregnenolone acetate. X-ray diffraction analysis of (1) demonstrated that it consisted of four rings, three six-membered rings (A, B and C) and one five-membered ring (D). A, B, C and D rings occur in an envelope, deformed chair, deformed chair, and the half chair conformations, respectively. The absolute configurations of 7 for the chiral centers are 3S, 8S, 9S, 10R, 13S and 14S. The crystal of 3β-(p-iodobenzoyloxy)-16α,17α-epoxypregn-4-en-6,20-dione is in monoclinic crystal system with space group P21, lattice constants: a = 10.8567 (11), b = 7.5479 (7), c = 16.0391 (16) Å, β = 109.473 (1)°, V = 1239.1 (2) Å3, Dx = 1.518 g/cm3 and Z = 2. The molecules in the crystal are stabilized by C-H···O interactions and van der Waals forces.