7-羟基-1,3-二甲基-2,4-二氧代-1,2,3,4-四氢吡啶并[2,3-D]嘧啶-6-羧酸

1,3-二甲基-2,4-二氧代-1H,2H,3H,4H-吡啶并[2,3-D]嘧啶-6-羧酸 1,3-二甲基-2,4-二氧代-1,2,3,4-四氢吡啶并[2,3-D]嘧啶-6-羧酸甲酯 1-methyl-2,4-dioxo-1H,2H,3H,4H-pyrido[2,3-d]pyrimidine-6-carboxylic acid 1,3,5-trimethyl-2,4-dioxo-1H,2H,3H,4H-pyrido[2,3-d]pyrimidine-6-carboxylic acid 1,3,8-三甲基-2,4,7-三氧代-1,2,3,4,7,8-六氢吡啶并[2,3-D]嘧啶-6-羧酸 1,3-二甲基-2,4,7-三氧代-1,2,3,4,7,8-六氢吡啶并[2,3-D]嘧啶-6-甲酸甲酯