title: Urinary metabolites of N-nitrosodibutylamine and N-nitrodibutylamine in the rat: identification of N-acetyl-S-alkyl-L-cysteines.
abstract: N-Acetyl-S-butyl-L-cysteine, N-acetyl-S-3-oxobutyl-L-cysteine and N-acetyl-S-3-hydroxybutyl-L-cysteine have been isolated and identified (as their methyl esters) from the urine of rats given N-nitrosodibutylamine (NDBA), N-nitrodibutylamine (NO2DBA) and their 1-acetoxy derivatives. Greater amounts of these N-acetyl-S-alkyl-L-cysteines were detected in the urine after administration of NDBA than of NO2DBA, and greater urinary excretion of the three N-acetyl-S-alkyl-L-cysteines was observed with 1-acetoxy NDBA than with 1-acetoxy NO2DBA. This suggests that the markedly different biological activities of NDBA and NO2DBA might be due, in part, to a difference in their alkylating abilities in vivo.
mesh_terms: D000478:Alkylation; D000818:Animals; D002082:Butylamines / Q000378:metabolism* / Q000652:urine; D003545:Cysteine / Q000031:analogs & derivatives* / Q000652:urine; D005978:Glutathione / Q000378:metabolism; D009153:Mutagens / Q000378:metabolism; D009602:Nitrosamines / Q000378:metabolism* / Q000652:urine; D051381:Rats
chemical_list: D002082:Butylamines; D009153:Mutagens; D009602:Nitrosamines; C045280:N-nitrodibutylamine; C012279:dibutylnitrosamine; D005978:Glutathione; D003545:Cysteine