阿奇霉素杂质B

diethyl 5-methyl-3-oxo-1,2,3,6-tetrahydro-[1,1'-biphenyl]-2,6-dicarboxylate

2,6-二甲基-4-苯基-1,4-二氢吡啶-3,5-二羧酸二乙酯

ethyl 4-methyl-2-oxo-6-phenylcyclohex-3-ene-1-carboxylate