138433-47-3

Spiro[oxirane-2,1'(2'H)-pentaleno[1,6a-c]pyran]- 5'-carboxylic acid,4',4'a,6'a,9'-tetrahydro-7',- 8'-dimethyl-2'-oxo-,(1'R,4'aR,6'aR,9'aR)-