Patent ID: 8772283

Claim:
An imidazooxazine compound represented by Formula (I) or a salt thereof, wherein A, B, C, and D represent an N atom or C—R 1a , an N atom or C—R 1b , an N atom or C—R 1c , and an N atom or C—R 1d , respectively; R 1a , R 1b , R 1c , and R 1d are the same or different, and each represents hydrogen, halogen, cyano, optionally substituted C 1-6 alkyl, optionally substituted C 1-6 alkoxy, substituted carbonyl, or an optionally substituted unsaturated heterocyclic group; R 2 represents optionally substituted aryl or an optionally substituted unsaturated heterocyclic group; and R 3 and R 4 are the same or different, and each represents hydrogen, hydroxy, optionally substituted C 1-6 alkyl, or optionally substituted C 3-7 cycloalkyl, and wherein a substituent of the substituted carbonyl is selected from the group consisting of: hydroxyl, amino, optionally substituted mono- or di-(C 1-6 alkyl)amino, and mono- or di-(C 1-6 alkoxy)amino; and wherein a substituent of the optionally substituted groups is selected from the group consisting of: halogen, hydroxyl, cyano, amino, nitro, oxo, carboxy, carbamoyl, alkyl, cycloalkyl, alkenyl, alkynyl, alkoxy, acyl, acyloxy, alkoxycarbonyl, saturated heterocyclic group, an unsaturated heterocyclic group, aryl, halogenoalkyl, aralkyl, saturated heterocyclic alkyl, alkylamino, acylamino, and aralkyloxy.