Crystal structures of 8β-methyltestosterone 17β-monobromoacetate and testosterone 17β-p-bromobenzoate

Abstract

The crystal structures of 8β-methyltestosterone 17β-monobromoacetate and testosterone 17β-p-bromobenzoate have been determined by three-dimensional X-ray diffraction methods from diffractometer data recorded with Mo-K_α radiation. The crystals of 8β-substituted testosterone C₂₂H₃₁O₃Br, are orthorhombic, a= 18·51, b= 10·36, c= 10·63 Å, Z= 4, space group, P2₁2₁2₁. The crystals of ‘normal’ testosterone C₂₆H₃₁O₃Br, are monoclinic, a= 17·79, b= 7·08, c= 18·05 Å, β= 95·02°, Z= 4, space group, C2. The structures were solved by the heavy-atom and three-dimensional Fourier methods, and refined by least-squares calculations. The molecular conformation, which contains the 8β-methyl, was clearly bent, in contrast with the planar overall shape of the ring system of ‘normal’ testosterone.