EPR Study of Hydrated Testosterone Monoclinic and Orthorhombic Single Crystals γ-irradiated at 295 K

Summary

The molecular structure of free radicals formed in γ-irradiated monoclinic and orthorhombic single crystals of hydrated testosterone were investigated by EPR spectroscopy. Two different types of radical were observed. In the monoclinic form, the radical arises by the loss of a hydrogen atom from the carbon atom C(2), whereas, in the orthorhombic form, it arises by addition of a hydrogen atom to the oxygen atom O(3). The hyperfine spectrum of the radical formed in the monoclinic single crystal originates from the interaction of the unpaired electron with one α-proton in position 2 and two non equivalent β-protons in position 1. In the orthorhombic single crystal, we observed interaction of the unpaired electron, which is delocalized on the carbons C(3), C(4) and C(5) with one α-proton in position 4 and with four nonequivalent β-protons connected with the carbon atoms C(2) and C(6). The hyperfine tensors of the coupling and the g-tensor of the radicals are given.

• steroids
• hormones
• single crystals
• testosterone
• EPR
• radicals