Methyl n-butyryl acetate is an organic intermediate. It has been reported that it can be used to prepare 4 (3H) - quinazolone derivatives. 4 (3H) - quinazoline ketone derivatives are a class of nitrogenous heterocyclic compounds with good biological and pharmacological activities in anticancer, antihypertensive, anti diabetic, anti-inflammatory, bactericidal, analgesic and so on.