THE THERMAL-STABILITY OF S-NITROSOTHIOLS - EXPERIMENTAL STUDIES AND AB-INITIO CALCULATIONS ON MODEL COMPOUNDS

One factor responsible for the enhanced thermal stability of S-nitroso -N-acetylpenicillamine (SNAP), compared with S-nitroso-N-acetylcystein e (SNAC), has been shown, by ab initio calculations on model compounds , to be steric interactions in the dimerisation reaction leading to di sulfide formation, Studies using DSC and TGA indicate that the two gem methyl groups in SNAP do not have a substantial effect on the strengt h of the -S-NO bond.