嘧啶 Traditional form: 嘧啶 Pinyin (reading): mìdìng Definitions: pyrimidine C4H4N2 Characters: 嘧 - in chemistry, -mi as in pyramidine 啶 - in chemistry, -dine Traditional characters: 嘧 - in chemistry, -mi as in pyramidine 啶 - in chemistry, -dine