Synthesis and radioprotective activity of new N-(amino acid)-S-acetylcysteamine and cystamine derivatives

In order to evaluate the influence of an amino acid conjugation (Sar, Ser, Phe, Pro, Thz) on S-acetylcysteamine, cystamine, N-(amino acid)-S-acetylcysteamine (14-18) and N,N'-bis (amino acid) cystamine (24-28) derivatives have been synthesized and evaluated as potential radioprotectors. Their toxicity and radioprotective activity, as the dose reduction factor (DRF) have been determined (in vivo; ip) and compared with cysteamine and cystamine parent compounds: N-glycyl-S-acetylcysteamine trifluoroacetate 1 and N,N'-bis (glycyl)cystamine bis (trifluoroacetate) 2. Among these compounds, 14 (Sar), 15 (Ser), 15a [Ser (Ac)], 16 [Phe], 24 (Sar) had significant radioprotective activity.