Leukotriene b4 inhibitors

A compound of formula (I):

• wherein:
• R1 is
• phenyl, unsubstituted or mono- or bi-substituted with alkoxy, halogen, hydroxy, lower alkyl, amino or amino-lower alkyl,
• heteroaryl, unsubstituted or substituted with lower alkyl or halogen,
• benzo[1,3]dioxole, unsubstituted or substituted with lower alkyl,
• dihydro-benzo[1,4]dioxine, unsubstituted or substituted with lower alkyl, benzo[b][1,4]dioxepine, unsubstituted or substituted with lower alkyl,
• dihydro-benzofuran, unsubstituted or substituted with lower alkyl, or
• benzo[1,4]oxazin, unsubstituted or substituted with lower alkyl;
• R2 and R3, independently of each other, are:
• hydrogen,
• lower alkyl,
• cycloalkyl,
• phenyl,
• lower alkyl-cycloalkyl,
• lower alkyl-heteroaryl,
• lower alkyl-alkoxy,
• alkoxy-lower alkyl,
• lower alkyl-heterocycloalkyl, unsubstituted or substituted with lower alkyl,
• C(O)-amino,
• lower alkyl-phenyl, said phenyl being unsubstituted or mono- or bi-substituted with lower alkyl, halogen, alkoxy or O-haloloweralkyl,
• benzo[1,3]dioxole, unsubstituted or substituted with lower alkyl,
• dihydro-benzo[1,4]dioxine, unsubstituted or substituted with lower alkyl,
• benzo[b][1,4]dioxepine, unsubstituted or substituted with lower alkyl,
• benzofuran, unsubstituted or substituted with lower alkyl,
• benzo[1,4]oxazin, unsubstituted or substituted with lower alkyl,
• CH2-benzo[1,3]dioxole, unsubstituted or substituted with lower alkyl,
• CH2-dihydro-benzo[1,4]dioxine, unsubstituted or substituted with lower alkyl,
• CH2-benzo[b][1,4]dioxepine, unsubstituted or substituted with lower alkyl,
• CH2-benzofuran, unsubstituted or substituted with lower alkyl
• CH2-benzo[1,4]oxazin, unsubstituted or substituted with lower alkyl, or
• R2 and R3, together with the nitrogen atom to which they are attached, form a heterocycloalkyl ring, optionally having a second heteroatom from N, O or S, said heterocycloalkyl ring being unsubstituted or mono- or bi-substituted with halogen, lower alkyl, carbonyl, C(═O) or hydroxy;
• X is O or C;
• and
• “a” is a single bond or an alkynyl bond,
• and pharmaceutically acceptable salts thereof.