InChI=1/C18H18O3/c1-21-18(20)16-11-12-7-5-6-8-13(12)14-9-3-2-4-10-15(14)17(16)19/h4-8,10,19H,2-3,9,11H2,1H benzo[a]heptalene-6-carboxylic acid, 5,10,11,12-tetrahydro-7-hydroxy-, methyl ester methyl 7-hydroxy-5,10,11,12-tetrahydrobenzo[a]heptalene-6-carboxylate