Piperazine derivatives having sst1 antagonistic activity

A compound of formula I

• wherein
• X is a single bond or —O—, —S—, —CH2—, —CH═CH— or —CH2—CH2—,
• R1 is (C1-4)alkyl, (C2-5)alkenyl or (C3-7)cycloalkyl(C1-4)alkyl, and
• R2 is a group of formula
• wherein
• Y is —O— or —S—,
• R3 and R4, independently, are hydrogen, hydroxy, halogen, nitro, cyano, trifluoromethyl, (C1-4)alkyl or (C1-4)alkoxy, and
• R5 is hydrogen or (C1-4)alkyl,
• in free base or acid addition salt form.