Phenothiazine-pyridine compounds and uses thereof

A phenothiazine-pyridine compound of formula (I):

• wherein:
• R1 and R3 are each
• R2 is H or halogen;
• R4 is H, halogen, —NH2, —OH, —CN, —NO2, —COCH3, —CF3, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 haloalkyl, C3-C6 cycloalkyl,
• R5 is H, halogen, —CN, —NO2, —COCH3, —CF3, C1-C12 alkyl, C1-C12 alkoxy, C1-C6 alkoxycarbonyl, C3-C6 cycloalkyl or C2-C10 N-alkyl amine;
• R6 and R7 are each independently H, C1-C12 alkyl, C3-C6 cycloalkyl, C3-C12 alkenyl, C3-C12 alkynyl, C2-C10 amine or C2-C10 substituted amine, aryl, CnH2nY, YCnH2nY, or when taken together, R6 and R7 with a nitrogen to which they are both attached form a 5 to 7 membered heterocyclic ring wherein any one carbon atom of said heterocyclic ring can optionally be replaced with —O—, —S—, —SO2— or —NR9—;
• each R8 is independently H, halogen, —NO2, —CN, —COCH3, —CF3, C1-C6alkyl, C1-C6 alkoxy, C3-C6cycloalkyl or aryl;
• each R9 is independently H, C1-C10 alkyl, C2-C9 carbonyl or C2-C9 sulfonyl;
• each n is independently an integer from 2 to 6;
• each X is independently selected from C1-C5 alkyl, O, S, NH2, NH or NR10);
• each Y is independently F, Cl, Br, I, OH, OMe, OC2H5, OC3H7, CN or OCOCH3;
• each R10 is independently C1-C6 alkyl, C1-C6 alkoxy, —NO2, —CN, —COCH3 or aryl;
• Z− is an organic or inorganic counter anion;
• or salts thereof.