吖嗪 [ㄚ ㄑㄧㄣˊ; a1 qin2] -azine heterocyclic compound containing nitrogen in their ring such as pyridine 吡啶[ㄅㄧˇ ㄉㄧㄥˋ; bi3 ding4] C5H5N, pyrazine 哒嗪[ㄉㄚ ㄑㄧㄣˊ; da1 qin2] C4H4N2 or pyrimidine 嘧啶[ㄇㄧˋ ㄉㄧㄥˋ; mi4 ding4] C4H4N2 ◄ ►