title: Presence of N-nitroso-L-thioproline and N-nitroso-L-methylthioprolines in human urine as major N-nitroso compounds.
abstract: Unknown N-nitroso compounds were found in human urine of healthy volunteers by gas chromatography-thermal energy analysis. These compounds were identified as N-nitroso-L-thioproline and cis- and trans-N-nitroso-L-methylthioprolines by gas chromatography-mass spectrometry. The precursors of these new N-nitroso compounds may be formed by the reactions of L-cysteine with formaldehyde and acetaldehyde in the human body.
mesh_terms: D002849:Chromatography, Gas; D006801:Humans; D009603:Nitroso Compounds / Q000652:urine*; D013844:Thiazoles / Q000652:urine*; D053778:Thiazolidines
chemical_list: C039002:N-nitroso-2-methylthioproline; D009603:Nitroso Compounds; D013844:Thiazoles; D053778:Thiazolidines; C039001:N-nitrosothioproline