3,5-isoxazoledicarboxylic acid, 4,5-dihydro-, diethyl ester InChI=1/C9H13NO5/c1-3-13-8(11)6-5-7(15-10-6)9(12)14-4-2/h7H,3-5H2,1-2H diethyl 4,5-dihydroisoxazole-3,5-dicarboxylate