

THREE-COMPONENT CONDENSATION OF 4-IMINO-1-PHENYLIMIDAZOLIDIN-2-ONE WITH ALDEHYDES AND MELDRUM'S ACID: SYNTHESIS OF IMIDAZO[4,5-b]PYRIDINE-2,5(4H,6H)-DIONES AND 5-SUBSTITUTED 1-PHENYLHYDANTOINS

Abstract
A convenient method for the synthesis of previously unknown imidazo[4,5-b]pyridine-2,5(4H,6H)-diones has been developed, based on a three-component condensation of 4-imino-1-phenylimidazolidin-2-one with aldehydes and Meldrum's acid. The possibility of accessing 5-substituted 1-phenylhydantoins based on the acid hydrolysis of imidazo[4,5-b]pyridine-2,5(4H,6H)-diones was shown.
Keywords
aldehydes; imidazo[4,5-b]pyridine-2,5(4H,6H)-diones; 4-imino-1-phenylimidazolidin-2-one; Meldrum's acid; 5-substituted 1-phenylhydantoins; three-component condensation.
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv