title: Selective inhibition of xanthine oxidase by substituted pyridopyrimidines.
abstract: Six 2-methyl-3-substituted-pyrido-(2,3-d)-pyrimidine 4 (3H)-ones were synthesized and evaluated for their ability to inhibit xanthine oxidase and other purine catabolizing enzymes of rat liver. All compounds inhibited xanthine oxidase selectively when tested at a final concentration of 0.5 mM in vitro. Adenosine deaminase, guanosine deaminase and guanine deaminase were unaffected. The inhibition of xanthine oxidase was found to be competitive in nature.
mesh_terms: D000619:Aminohydrolases / Q000037:antagonists & inhibitors; D000818:Animals; D066298:In Vitro Techniques; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D011725:Pyridines / Q000138:chemical synthesis / Q000494:pharmacology; D011744:Pyrimidinones / Q000138:chemical synthesis / Q000494:pharmacology*; D051381:Rats; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors*
chemical_list: D011725:Pyridines; D011744:Pyrimidinones; D014969:Xanthine Oxidase; D000619:Aminohydrolases