Glucuronides formed from drugs

To prepare glucuronide conjugates of products formed from initial oxidation (to yield a hydroxyl or carboxylic acid group), the oxidative metabolite should be prepared first and used as a substrate in the incubation. Alternatively, an incubation with parent drug, NADPH and UDPGA may produce the desired glucuronide. 

Third in importance are the S-glucuro-nides formed from aliphatic and aromatic thiols (reaction 12 in Fig. 13.21) and from di-thiocarboxylic acids (reaction 13) such as di-ethyldithiocarbamic acid, a metabolite of dis-ulfiram. As for C-glucuronidation (reaction 14), this reaction has been seen in humans for 1,3-dicarbonyl drugs such as phenylbutazone and sulfinpyrazone (28) (Fig. 13.23). 

Some S-glucuronides are formed from aliphatic thiols, aromatic thiols and dithiocarboxylic acids. As for C-glucuronidation, this reaction is seen in humans for 1,3-dicarbonyl drugs, such as sulfinpyrazone. 

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