Phthalazine derivatives as inhibitors of protein kinase

A compound of formula III:

• wherein
• X is hydrogen, halogen, alkyl, aryl, heteroaryl, cyano or alkoxy;
• R′ is hydrogen, alkyl, —C(O)Rx, —SO2Rx or —P(O)(ORx)2, where Rx is hydrogen or alkyl;
• R11 and R12 are each independently hydrogen, halogen, hydroxy, cyano, amino, alkyl, alkenyl, alkynyl, heterocyclyl, alkoxy, alkythio, arylthio, -alkylene-NRaRb, C(O)Ra, —C(O)NRaRb, -alkylene-C(O)NRaRb, —C(O)ORa, —C(S)NRaRb, —C(S)Ra, —C(O)SRa, NO2, NH2, —NRaC(O)Rb, —NRaRb, —NRaORb, —NRaC(S)Rb, —NRaC(O)NRbRc, —NRaC(S)NRbRc, —NRa(COORb), —NRaS(O)2NRbRc, —NRaS(O)Rb, —NRaS(O)2Rb, —ORa, —OC(O)Ra, —ONRaRb, —OC(O)NRaRb, —SRa, —S(O)2Ra, or —S(O)2NRaRb, wherein Ra, Rb and Rc are each independently hydrogen, hydroxy, cyano, nitro, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, alkylaryl, haloaryl, heteroaryl, alkylheteroaryl, alkylheterocyclyl, alkoxy, alkythio, arylthio, or alkoxycarbonyl, wherein, if present, an aryl, alkylaryl, heteroaryl, alkylheteroaryl, heterocyclyl, or alkylheterocycyl may be substituted, in one or more positions with a substituent or a combination of substituents selected from halogen, hydroxy, cyano, nitro, amino, carboxyl, alkyl, alkenyl, alkynyl, alkoxy, alkylamino, alkylthio, —C(O)NRd-alkylheterocyclyl (in which Rd is H or alkyl), O-alkylheterocyclyl, alkylheterocyclyl, aryl, heteroaryl, heterocyclyl, aryloxy, alkylamino, dialkylamino, aminoalkyl, -alkylene-O-alkyl, —NReC(O)Rf, —NRe(alkylene-NReRf), —NRe(alkylheterocyclyl), and —O-alkylene-NReRf (in which Re and Rf are independently hydrogen or alkyl;
• wherein at least one of R11 or R12 is -alkylene-C(O)NRaRb, -alkylene-NRaRb, —C(O)NRaRb, —NRaC(O)Rb or —NRaRb;
• and pharmaceutically acceptable salts thereof,
• provided that said compound is not:
• N-(3,4-dihydro-4-oxo-6-phthalazinyl)-2-methyl-2-propenamide,
• N-(1,2-dihydro-1-oxo-6-phthalazinyl)-2-methyl-2-propenamide,
• 7-(cyclohexylamino)-6-(phenylamino)-1(2H)-phthalazinone,
• 6,7-bis(phenylamino)-1(2H)-phthalazinone,
• 6-amino-7-chloro-1(2H)-phthalazinone,
• or a pharmaceutically acceptable salt thereof.