Sulfamates and methanesulfonates of l-arginine and l-histidine

Reactions of l-arginine (L-Arg) and l-histidine (L-His) with sulfamic (NH2SO3H) and methanesulfonic (CH3SO3H) acids in aqueous media were investigated. The following salts (L-ArgH)(NH2SO3) (I), (L-ArgH)(CH3SO3) (II), (L-ArgH2)(CH3SO3)2 (III), (L-HisH)(NH2SO3) (IV), (L-HisH2)(NH2SO3)2 (V), (L-HisH)(CH3SO3).2H2O (VI), (L-HisH2)(CH3SO3)2 (VII) were obtained and characterized structurally and by vibrational spectroscopy. Large crystals of (II), (VI), (VII) were grown from aqueous solution by evaporation method. The crystal (IV) was known previously and characterized spectroscopically, however, the published infrared spectrum significantly differs from our spectrum.