Naphthyridinone derivatives and their use in the treatment, amelioration or prevention of a viral disease

A compound having the formula (V), optionally in the form of a pharmaceutically acceptable salt, solvate, polymorph, prodrug, codrug, cocrystal, tautomer, racemate, enantiomer, or diastereomer or mixture thereof,

• wherein
• X51 is N;
• X52—X54 is C—R57;
• X53 is NR55, N(R55)C(O), C(O)NR55, O, C(O), C(O)O, OC(O);
• N(R55)SC2, SO2N(R55), S, SO, or SO2;
• R50 is —H, -(optionally substituted C1-6 alkyl), -(optionally substituted C3-7 cycloalkyl), -(optionally substituted aryl), —C1-4 alkyl -(optionally substituted C3-7 cycloalkyl), or —C1-4 alkyl -(optionally substituted aryl);
• R51 is —H, a —C1-6 alkyl group, or a —C1-6 alkyl group which is substituted by one or more halogen atoms;
• R52 is —H, a —C1-6 alkyl group, or a —C1-6 alkyl group which is substituted by one or more halogen atoms;
• or wherein R51 and R52 can be joined together to form a 3- to 7-membered carbo- or heterocyclic ring;
• R53 is —R56, or —X53—R56;
• R55 is —H, -(optionally substituted C1-6 alkyl), -(optionally substituted C3-7 cycloalkyl), -(optionally substituted aryl), —C1-4alkyl -(optionally substituted C3-7 cycloalkyl), or —C1 4alkyl -(optionally substituted aryl);
• R56 is -(optionally substituted hydrocarbon group which contains from 5 to 20 carbon atoms and optionally 1 to 4 heteroatoms selected from O, N and S and which contains at least one ring);
• R57 is —H, -Hal or —C1-6 alkyl;
• R58 is —H, —C1-6 alkyl, or —(CH2CH2O)rH;
• R59 is —H, or —C1-6 alkyl;
• R is independently selected from —C1 alkyl, —C(O)—C1-6 alkyl, -Hal, —CF3, —CN, —COOR58, —OR58, —(CH2)qNR58R59, —C(O)—NR58R59, and —NR58—C(O)—C1-6 alkyl;
• q is 0 to 4;
• and
• r is 1 to 3;
• wherein the alkyl group, aryl group, hydrocarbon group and/or cycloalkyl group can be optionally substituted with one or more substituents R.
• with the proviso that the following compounds are disclaimed:
• and
• ethyl 4-oxo-1-{[4-(1H-pyrazolo-1-yl)phenyl]methyl}-1,4-dihydro-1,5-naphthyridine-3-carboxylate.