Compounds having the structural formula I are disclosed, wherein A is alkylene, or optionally substituted arylene, cycloalkylene or heteroaryldiyl; X is —C(O)— or —S(O)2—; R1 is alkyl or cycloalkyl; R2 is hydrogen, halo or —CN; R3 is hydrogen or alkyl; R4 is hydrogen, alkyl, alkoxy, hydroxyalkyl, aminoalkyl-, cycloalkyl, heterocycloalkyl, heterocycloalkyl substituted by alkyl, optionally substituted arylalkyl or optionally substituted heteroarylalkyl; or R3 and R4, form an optionally substituted 5-7 membered ring, said ring optionally comprising an additional heteroatom ring member; R7 is alkyl, optionally substituted phenyl, optionally substituted heteroaryl, cycloalkyl, halo, morpholinyl, optionally substituted piperazinyl, or optionally substituted azacycloalkyl. Also disclosed is the use of the compounds in the treatment of Parkinson's disease, alone or in combination with other agents for treating Parkinson's disease, pharmaceutical compositions comprising them and kits comprising the components of the combinations.