A compound of the formula: wherein: Z is -CH=CH-, -(CH 2) p, wherein p is 0, 1, 2 or 3, NH, O, S, >S=O, >SO 2 or > C=O; R is an optionally substituted linear or branched C 1 -C 7 alkyl, C 2 -C 7 alkenyl or C 2 -C 7 alkynyl, C 3 -C 7 cycloalkyl, C 4 -C 7 cycloalkenyl, phenyl, naphthyl, 5- or 6- membered heteroaryl, saturated or partially saturated heterocyclic ring comprising one or more oxygen, sulfur or nitrogen atom, or is a group CONHR 2, CH 2 NHR 2, NHCOR 2, NHCONHR 2 wherein R 2 is an optionally substituted linear or branched C 1 -C 7 alkyl, C 2 -C 7 alkenyl or C 2 -C 7 alkynyl, C 3 -C 7 cycloalkyl, C 4 -C 7 cycloalkenyl group, phenyl, naphthyl, 5- or 6- membered heteroaryl, saturated or partially saturated heterocyclic ring comprising one or more oxygen, sulfur or nitrogen atom; X is N, NH or O; W is CH and Y is N, NH or O; R 1 is NH 2, NHCONHR 2, NHCOR 2, NHSO 2 R 2, or CONHR 2 group, wherein R 2 is as defined above; the ring containing X, Y and W as defined above being a heteroaryl group, wherein the optional substituents herein are independently selected from: halogen, nitro, oxo groups (=O),cyano, C 1 -C 6 alkyl, polyfluorinated alkyl, polyfluorinated alkoxy, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, hydroxyalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, heterocyclyl, heterocyclylalkyl, C 3 -C 7 cycloalkyl, hydroxy, alkoxy, aryloxy, heterocyclyloxy, methylenedioxy, alkylcarbonyloxy, arylcarbonyloxy, cycloalkenyloxy, heterocyclylcarbonyloxy, alkylideneaminooxy, carboxy, alkoxycarbonyl, aryloxycarbonyl, cycloalkyloxycarbonyl, heterocyclylalkyloxycarbonylamino, ureido, alkylamino, dialkylamino, arylamino, diarylamino, heterocyclylamino, formylamino, alkylcarbonylamino, arylcarbonylamino, heterocyclylcarbonylamino, aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl, arylaminocarbonyl, heterocyclylaminocarbonyl, alkoxycarbonylamino, hydroxyaminocarbonyl alkoxyimino, alkylsulfonylamino, arylsulfonylamino, heterocyclylsulfonylamino, formyl, alkylcarbonyl, arylcarbonyl, cycloalkylcarbonyl, heterocyclylcarbonyl, alkylsulfonyl, arylsulfonyl, aminosulfonyl, alkylaminosulfonyl, dialkylaminosulfonyl, arylaminosulfonyl, heterocyclylaminosulfonyl, arylthio, alkylthio, phosphonate and alkylphosphonate, in their turn, whenever appropriate, each of the above substituent may be further substituted by one or more of the aforementioned groups; or a pharmaceutically acceptable salt thereof. Z is -CH=CH-, -(CH 2) p, wherein p is 0, 1, 2 or 3, NH, O, S, >S=O, >SO 2 or > C=O; R is an optionally substituted linear or branched C 1 -C 7 alkyl, C 2 -C 7 alkenyl or C 2 -C 7 alkynyl, C 3 -C 7 cycloalkyl, C 4 -C 7 cycloalkenyl, phenyl, naphthyl, 5- or 6- membered heteroaryl, saturated or partially saturated heterocyclic ring comprising one or more oxygen, sulfur or nitrogen atom, or is a group CONHR 2, CH 2 NHR 2, NHCOR 2, NHCONHR 2 wherein R 2 is an optionally substituted linear or branched C 1 -C 7 alkyl, C 2 -C 7 alkenyl or C 2 -C 7 alkynyl, C 3 -C 7 cycloalkyl, C 4 -C 7 cycloalkenyl group, phenyl, naphthyl, 5- or 6- membered heteroaryl, saturated or partially saturated heterocyclic ring comprising one or more oxygen, sulfur or nitrogen atom; X is N, NH or O; W is CH and Y is N, NH or O; R 1 is NH 2, NHCONHR 2, NHCOR 2, NHSO 2 R 2, or CONHR 2 group, wherein R 2 is as defined above; the ring containing X, Y and W as defined above being a heteroaryl group, wherein the optional substituents herein are independently selected from: halogen, nitro, oxo groups (=O),cyano, C 1 -C 6 alkyl, polyfluorinated alkyl, polyfluorinated alkoxy, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, hydroxyalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, heterocyclyl, heterocyclylalkyl, C 3 -C 7 cycloalkyl, hydroxy, alkoxy, aryloxy, heterocyclyloxy, methylenedioxy, alkylcarbonyloxy, arylcarbonyloxy, cycloalkenyloxy, heterocyclylcarbonyloxy, alkylideneaminooxy, carboxy, alkoxycarbonyl, aryloxycarbonyl, cycloalkyloxycarbonyl, heterocyclylalkyloxycarbonylamino, ureido, alkylamino, dialkylamino, arylamino, diarylamino, heterocyclylamino, formylamino, alkylcarbonylamino, arylcarbonylamino, heterocyclylcarbonylamino, aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl, arylaminocarbonyl, heterocyclylaminocarbonyl, alkoxycarbonylamino, hydroxyaminocarbonyl alkoxyimino, alkylsulfonylamino, arylsulfonylamino, heterocyclylsulfonylamino, formyl, alkylcarbonyl, arylcarbonyl, cycloalkylcarbonyl, heterocyclylcarbonyl, alkylsulfonyl, arylsulfonyl, aminosulfonyl, alkylaminosulfonyl, dialkylaminosulfonyl, arylaminosulfonyl, heterocyclylaminosulfonyl, arylthio, alkylthio, phosphonate and alkylphosphonate, in their turn, whenever appropriate, each of the above substituent may be further substituted by one or more of the aforementioned groups; or a pharmaceutically acceptable salt thereof.