The spectroscopic features of free radicals produced in gamma irradiation of the N-methyl-dlalanine, N,N -dimethyl glycine hydrochloride and d -( + ) -galactosamine hydrochloride were investigated at room temperature at the dose 15 kGy using EPR technique. The paramagnetic species observed in these compounds were identified as CH 3Ċ HCOOH,ĊHOH(CHOH) 3 NH 2 (CH) 2 O, and (CH 3 ) 2 NĊHCOOH.HCl, respectively. A comparison with a new paramagnetic species recently observed and characterized in irradiated amino acids indicates that the new radical presented here has a similar structure. In this paper, we have also studied the stability of these compounds at room temperature after irradiation.