InChI=1/C15H18O4/c1-4-18-14(16)13(15(17)19-5-2)10-12-8-6-11(3)7-9-12/h6-10H,4-5H2,1-3H diethyl (4-methylbenzylidene)malonate propanedioic acid, [(4-methylphenyl)methylene]-, diethyl ester