Catalyst-free and oxidant-free cyclocondensation of 2-aminobenzamides with glycosides under visible light

A convenient and practical method for the mild synthesis of quinazolinones has been developed under visible light at room temperature in the absence of catalysts or additional oxidants. Under very mild reaction conditions, the quinazolinone moiety can be successfully introduced into deoxyuridine and helicid. This method afforded various 5-substituted deoxyuridine analogs and 4-substituted helicid derivatives in moderate to good yields (without column chromatography) across diverse aromatic and aliphatic aldehydes, proving effective for late-stage drug functionalization.