An efficient synthesis of tetrasubstituted unsymmetrical pyrazines and their related pyrazine N-oxides has been developed from commercially available 2-chloro-3-methylpyrazine. The procedure and scope of these synthesis routes are described.

中文翻译：

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四取代吡嗪和吡嗪N-氧化物的合成

从商业上可获得的2-氯-3-甲基吡嗪已经开发了四取代的不对称吡嗪及其相关的吡嗪N-氧化物的有效合成。描述了这些合成路线的过程和范围。