Pyrazolo-quinazoline derivatives, process for their preparation and their use as kinase inhibitors

1) A pyrazolo-quinazoline derivative represented by formula (Ia) or (Ib)

• wherein
• R is hydrogen or an optionally substituted group selected from amino, straight or branched C1-C6 alkyl, C3-C10 cycloalkyl, aryl, arylalkyl, heterocyclyl or heterocyclylalkyl;
• X is a single bond or a divalent radical selected from —NR′—, —CONR′—, —NH—CO—NH—, —O—, —S— or —SO2—, wherein R′ is hydrogen or an optionally substituted group selected from straight or branched C1-C6 alkyl C3-C6 cycloalkyl, aryl, arylalkyl, heterocyclyl, heterocyclylalkyl or, together with the nitrogen atom to which they are bonded, R and R′ may form a 5 to 6 membered heteroaryl or heterocyclyl group optionally containing one additional heteroatom selected among N, O or S;
• R1, bonded to any one of the nitrogen atoms of the pyrazole ring as per formulae (Ia) or (Ib), represents a hydrogen atom or an optionally substituted group selected from straight or branched C1-C6 alkyl, C3-C6 cycloalkyl, aryl, arylalkyl, heterocyclyl or heterocyclylalkyl or, in formula (Ib), R1 is a divalent —(CH2)n—NH— group being linked to R2, wherein n is 2 or 3;
• R2 is a group selected from —NR″R′″, —N(OH)R″, —OR″ or —R″, wherein R″ and R′″ are, each independently, hydrogen or an optionally substituted group selected from straight or branched C1-C6 alkyl, C3-C6 cycloalkyl or cycloalkyl-alkyl, aryl, arylalkyl, heterocyclyl or heterocyclylalkyl or, together with the nitrogen atom to which they are bonded, R″ and R′″ may form a 5 to 6 membered heteroaryl or heterocyclyl group, optionally containing one additional heteroatom selected among N, O or S;
• A is a divalent group selected from —CH2—, —(CH2)2—, —CH2—C(CH3)2—, —C(CH3)2—CH2— or —CH═CH;
• or a pharmaceutically acceptable salt thereof.