InChI=1/C12H13NO/c14-11-9-5-1-2-6-10(9)13-12(11)7-3-4-8-12/h1-2,5-6,13H,3-4,7-8H spiro[cyclopentane-1,2'-[2H]indol]-3'(1'H)-one spiro[cyclopentane-1,2'-indol]-3'(1'H)-one