An irreversible Btk inhibitor for use in the treatment of proliferative disorders of B lymphocytes, said irreversible Btk inhibitor has the formula D: ** Formula ** in which: La is CH2, O, NH or S； Ar is a substituted or unsubstituted aryl or a substituted or unsubstituted heteroaryl； Y is an optionally substituted group selected from alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl and heteroaryl； Z is C (>； = O), OC (>； = O), NHC (>； = O), C (>； = S), S (>； = O) x, OS (>； = O) x, NHS (>； = O) x, where x is 1 or 2； R7 and R8 are independently selected from H, unsubstituted C1-C4 alkyl, substituted C1-C4 alkyl, unsubstituted C1-C4 heteroalkyl, substituted C1-C4 heteroalkyl, unsubstituted C3-C6 cycloalkyl, substituted C3-C6 cycloalkyl, C2 heterocycloalkyl -C6 unsubstituted and substituted C2-C6 heterocycloalkyl； or R7 and R8 together form a bond； R6 is H, substituted or unsubstituted C1-C4 alkyl, substituted or unsubstituted C1-C4 heteroalkyl, C1-C8 alkoxyalkyl, C1-C8 alkylaminoalkyl, substituted or unsubstituted C3-C6 cycloalkyl, substituted or unsubstituted aryl, C2- heterocycloalkyl C8 substituted or unsubstituted, substituted or unsubstituted heteroaryl, (C1-C4) alkyl aryl, (C1-C4) alkyl heteroaryl, (C1-C4) alkyl cycloalkyl (C3-C8) or (C1-C4) alkyl heterocycloalkyl (C2 -C8)； and pharmaceutically acceptable solvates or pharmaceutically acceptable salts thereof.Un inhibidor irreversible de Btk para usar en el tratamiento de transtornos proliferativos de los linfocitos B, dicho inhibidor irreversible de Btk tiene la fórmula D: **Fórmula** en la que: La es CH2, O, NH o S； Ar es un arilo sustituido o no sustituido o un heteroarilo sustituido o no sustituido； Y es un grupo opcionalmente sustituido seleccionado entre alquilo, heteroalquilo, cicloalquilo, heterocicloalquilo, arilo y heteroarilo； Z es C(>；=O), OC(>；=O), NHC(>；=O), C(>；=S), S(>；=O)x, OS(>；=O)x, NHS(>；=O)x, donde x es 1 ó 2； R7 y R8 se seleccionan independientemente entre H
