Heterocylic antiviral compounds

A compound according to formula I wherein:

• one of R1 and R2 is phenyl optionally substituted with one to four substitutents selected independently in each incidence from the group consisting of halogen, C1-6 alkyl and C1-6 alkoxy;
• and, the other of R1 and R2 is hydrogen;
• R3 is selected from the group consisting of:
• (a) C3-7 cycloalkyl optionally substituted with 1 to 4 fluorines, cyano, hydroxyl, C1-3 alkyl or phenyl, 4-oxo-cyclohexyl or 3-oxo-cyclobutyl;
• (b) heterocycle selected from the group consisting of IIa-c, oxetanyl and tetrahydrofuranyl,
• wherein:
• R8 is hydrogen, COR9, COCHR14NHR15 or SO2R10;
• and,
• R9 is C1-6 alkyl or C3-7 cycloalkyl;
• R10 is C1-6 alkyl;
• R14 is the side chain of naturally occurring amino acid;
• R15 is hydrogen, tert-butoxycarbonyl or benzyloxycarbonyl;
• (c) C1-6 alkyl;
• and
• (d) C1-6 alkoxy;
• R6 is hydrogen, C1-3 alkyl, C1-3 haloalkyl, C1-6 hydroxyalkyl or oxo-C1-6 alkyl;
• R6a, R6b, R6c and R6d are independently hydrogen or C1-3 alkyl with the proviso that at least one of R6c is hydrogen;
• X1 is selected from the group consisting of (i)-(ix) and (x):
• wherein
• X2 is N or CH;
• X2a is N, CH or CCl;
• A1 is phenylene or C1-6 straight or branched alkylene optionally substituted by a phenyl ring;
• R5 is hydroxy, C1-6 alkoxy, benzyloxy or NR6aR6b;
• wherein:
• R7 is C3-7 cycloalkyl, (CH2)nCOR5, heteroaryl selected from the group consisting of pyridine, pyrimidine, pyrazine and pyridazine said heteroaryl optionally substituted with C1-3 alkyl or C1-3 haloalkyl;
• n is 1 to 3;
• wherein
• R11 and R12 are (A) together a group (CH2)2X4(CH2)2, (CH2)2CH(R16)CH2, or (CH2)2SO2;
• or, (B) independently R12 is hydrogen or C1-3 alkyl and R11 is —SO2C1-6 alkyl, C1-6 hydroxyalkyl, xA, xB or xC;
• X4 is O, S(O)m, NR13 or CH(NHSO2C1-6 alkyl);
• R13 is R6d, —C(O)C1-6 alkyl, S(O)2C1-6 alkyl;
• R16 is hydrogen, hydroxyl or C1-10 acyloxy;
• m is zero to two;
• and,
• or pharmaceutically acceptable salts, hydrates or solvates thereof.