Pyrido-imidazo rifamycins

A compound of Formula (I) or pharmaceutically acceptable salts thereof

• wherein
• R and R1 may be H,
• with the proviso that:
• when
• then R1═H and R2═CH3CO— or H;
• when
• then R═H and R2═CH3CO— or H;
• when
• then R1═H and R2═CH3CO— or H;
• and
• when
• then R═H and R2═CH3CO— or H;
• wherein R3 and R4 are the same or different and selected from the group comprising hydrogen, linear or branched C1-C10 alkyl, optionally substituted with one or more substituents selected from aminoalkyl, alkoxy, phenoxy, or sulfo, and aryl, optionally mono- or disubstituted with C1-C4 alkyl or alkoxy groups, halogen, amino, nitro;
• or
• R3 and R4 taken together with two consecutive carbon atoms of the pyridine core may form a phenyl ring, optionally substituted with C1-C4 alkyl, or a 5- or 6-membered heterocyclic ring, optionally substituted with C1-C4 alkyl,
• R5 is selected from the group comprising hydrogen, hydroxy, linear or branched C1-C10 alkyl, optionally substituted with one or more substituents selected from aminoalkyl, alkoxy, phenoxy, or sulfo, and aryl optionally mono- or disubstituted with C1-C4 alkyl or alkoxy groups, halogen, amino, nitro.