Electron paramagnetic resonance study of gamma induced free radicals in single crystal of 1-[2-(1-ethoxy-carbonyl-3-phenylpropylamino)propionyl]octahydrocylo-penta[b]pyrrole-2-carboxylic acid

The aim of this study was to investigate the structure of the radicals produced by gamma irradiation on single crystals of 1-[2-(1-ethoxy-carbonyl-3-phenyl propyl amino) propionyl]octahydrocylo-penta[b]pyrrole-2-carboxylic acid (C23H32N2O5) by using electron paramagnetic resonance spectroscopy technique. The radiation-induced free radical of single crystals was studied at the temperatures between 120 and 300 K and it has been found that gamma-irradiation produced the CγH2CβH2ĊNH(COOC2H5) radicals. The hyperfine coupling constants and the g value of the free radical was reported as ACβH2CγH2 = 1.37 mT, aN = 1.10 mT and g = 2.0061. The free radical formed in compound was observed to be stable at 300 K during two months of gamma-irradiation. The results were observed as being in good conformity with the existing literature. •The radiation induced free radical in single crystals of ramipril has been investigated by EPR technique.•The spin Hamiltonian parameters of the CγH2CβH2ĊNH(COOC2H5)radical were calculated through EPR spectra.•The EPR spectra of radical found to be remained unchanged for two months.