Imidazo[2,1-G][1,7]naphthyridines for treating respiratory syncytial virus infections

A compound of formula (I), racemates, stereoisomers and/or salts thereof:

• wherein
• X1 is N and X2 is CH;
• R1 is selected from a carbocyclic ring, a heterocyclic ring, an aromatic ring, a substituted carbocyclic ring, a substituted heterocyclic ring, and a substituted aromatic ring, wherein the substituent is one or more groups selected from C1-6alkyl, C2-6alkenyl, C2-6alkynyl, aryl, halogen, halo C1-6alkyl, haloC2-6alkenyl, haloC2-6alkynyl, haloaryl, hydroxyl, C1-6alkylhydroxy, C1-6alkoxy, —OC1-6alkylhydroxy, —OC1-6alkylC1-6alkoxy, C2-6alkenyloxy, aryloxy, benzyloxy, haloC1-6alkoxy, haloC2-6alkenyloxy, haloaryloxy, nitro, nitroC1-6alkyl, nitroC2-6alkenyl, nitroC2-6alkynyl, nitroaryl, nitroheterocyclyl, amino, C1-6alkylamino, C1-6dialkylamino, C2-6alkenylamino, C2-6alkynylamino, arylamino, diarylamino, benzylamino, dibenzylamino, acyl, C2-6alkenylacyl, C2-6alkynylacyl, arylacyl, acylamino, diacylamino, acyloxy, alkylsulphonyloxy, arylsulphonyloxy, heterocyclyl, heterocyclyloxy, heterocyclylamino, haloheterocyclyl, alkylsulphonyl, arylsulphonyl, mercapto, C1-6alkylthio, benzylthio, and acylthio;
• R2 is selected from C1-6alkyl, haloC1-3alkyl and C1-3alkoxy;
• and
• R3 is H, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, aryl, halogen, haloC1-6alkyl, haloC2-6alkenyl, haloC2-6alkynyl, haloaryl, hydroxy, C1-6alkylhydroxy, C1-6alkoxy, —OC1-6alkylhydroxy, —OC1-6alkylC1-6alkoxy, C2-6alkenyloxy, aryloxy, benzyloxy, haloC1-6alkoxy, haloC2-6alkenyloxy, haloaryloxy, nitro, nitroC1-6alkyl, nitroC1-6alkenyl, nitroC1-6alkynyl, nitroC2-6alkenyl, nitroC2-6alkynyl, nitroaryl, nitroheterocyclyl, amino, C1-6alkylamino, C1-6dialkylamino, C2-6alkenylamino, C2-6alkynylamino, arylamino, diarylamino, benzylamino, dibenzylamino, acyl, C2-6alkenylacyl, C2-6alkynylacyl, arylacyl, acylamino, diacylamino, acyloxy, alkylsulphonyloxy, arylsulphonyloxy, heterocyclyl, heterocyclyloxy, heterocyclylamino, haloheterocyclyl, alkylsulphonyl, arylsulphonyl, mercapto, C1-6alkylthio, benzylthio, or acylthio.