This study describes the reduction of 4-methyl- and 4-phenyl-3-(methylsulfonyl)pyrazolo[5,1-c][1,2,4]triazines and 3-[(4-methylphenyl)sulfonyl]pyrazolo[5,1-c][1,2,4]triazines, which were obtained by reactions of pyrazole-3(5)-diazonium salts with the appropriate β-ketosulfones. The interaction of sulfonyl derivatives of pyrazolo[5,1-c][1,2,4]triazines with sodium dithionite or thiourea 1,1-dioxide under mild conditions resulted in chemospecific partial reduction of the as-triazine ring. The configuration of the obtained pyrazolo[5,1-c][1,2,4]triazine dihydro derivatives was established by X-ray structural analysis.

中文翻译：

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吡唑并[5,1-c] [1,2,4]三嗪的磺酰基衍生物的-三嗪环还原反应的化学特异反应

这项研究描述了4-甲基和4-苯基-3-（甲基磺酰基）吡唑并[5,1- c ] [1,2,4]三嗪和3-[（4-甲基苯基）磺酰基]吡唑并[5]的还原，1- c ] [1,2,4]三嗪，是通过吡唑-3（5）-重氮盐与适当的β-酮砜反应制得的。吡唑并衍生物磺酰的相互作用[5,1- c ^ ] [1,2,4]用连二亚硫酸钠或温和的条件下的硫脲1,1-二氧化物三嗪导致的chemospecific部分还原为三嗪环。通过X射线结构分析建立了所获得的吡唑并[5，1- c ] [1,2,4]三嗪二氢衍生物的构型。