New inhibitors of histone deacetylases having antitumor activity, and theprocess of preparation thereof are herein described. These compounds belong tothe structural formula (I) where R1 is a linear or branched chain containingat least two conjugated double bonds, A is an optionally substituted phenyl orpyridyl ring, Ar is an aryl or heteroaryl group, and R3 is hydrogen oralkoxyalkyl. The application also describes the use of said compounds in thetreatment of diseases associated to the deregulation of histone deacetylasesactivity, such as tumors, as well as the relevant pharmaceutical compositionsfor administration to patients requiring said treatment.
