3,5-DICARBETHOXY-1,4-DIHYDRO-2,4,6-TRIMETHYLPYRIDINE3,5-二乙氧基羰基-1,4-二氢-2,4,6-三甲基吡啶Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylateDDC1,4-二氢-2,4,6-三甲基-3,5-吡啶二甲酸二乙酯3,5-Dicarbethoxy-1,4-dihydrocollidine3,5-bis(ethoxycarbonyl)-1,4-dihydrocollidine3,5-diethoxycarbonyl-1,4-dihydrocollidinedicarbethoxydihydrocollidineDDC