Natural and synthetic inhibitors of UDP-glucuronosyltransferase.

Glucuronidation is a major detoxification pathway in vertebrates. The reaction is catalyzed by a family of UDP-glucuronosyltransferases (UGTs) and involves conjugation of many endobiotic and xenobiotic substances with glucuronic acid, forming inactive water-soluble glucuronides. UGT prevents the accumulation of potentially toxic compounds and/or their subsequent bioactivation to more toxic intermediates, although biologically active glucuronides are also known.

Synthesis and antitumour activity of several new 4-aroyl-1-nitrosohydrazinecarboxamides.

Six new analogues of nitrosoureas containing aroylhydrazine residue have been synthesized: (I) 4-(2-fluorobenzoyl)-1-(2-chloroethyl)-1-nitrosohydrazinecarboxamide++ +; (II) 4-(4-bromobenzoyl)-1-(2-chloroethyl)-1-nitrosohydrazinecarboxam ide; (III) 4-(4-hydroxybenzoyl)-1-(2-chloroethyl)-1-nitrosohydrazinecarboxamide+ ++; (IV) 4-(3-methoxybenzoyl)-1-(2-chloroethyl)-1-nitrosohydrazinecarbox amide; (V) 4-(4-methoxybenzoyl)-1-(2-chloroethyl)-1-nitrosohydrazinecarbox amide; (VI) 4-(4-fluorophenylacetyl)-1-(2-chloroethyl)-1-nitrosohydrazineca rboxamide. All six compounds showed a dose-dependent in vivo activity against leukaemias L1210 and P388. Compounds I and III were soluble in water.