The regioselective synthesis of twenty novel [3-substituted 5-hydroxy-5-(trifluoromethyl)-4,5-dihydro-1H-pyrazol-1-yl][6-aryl-(2-methylthio)pyrimidin-4-yl]methanones from the cyclocondensation reactions of new 6-aryl-2-(methylthio)pyrimidine-4-carbohydrazides with 4-substituted 1,1,1-trifluorobut-3-en-2-ones is reported. Human acetylcholinesterase (HsAChE) and butyrylcholinesterase (HsBChE) inhibition tests were performed on selected products in order to explore the possible pharmacological applications of these compounds. Two compounds showed significant and selective inhibitory activity for BChE.

中文翻译：

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具有药理学意义的吡唑基-嘧啶杂种的区域选择性合成

二十种新型[3-取代的5-羟基-5-（三氟甲基）-4,5-二氢-1H-吡唑-1-基] [6-芳基-（2-甲硫基）嘧啶-4-基]的区域选择性合成报道了新的6-芳基-2-（甲硫基）嘧啶-4-碳酰肼与4-取代的1,1,1-三氟丁-3-烯-2-酮的环缩合反应中的甲酮。为了研究这些化合物的可能药理应用，对选定的产品进行了人乙酰胆碱酯酶（Hs AChE）和丁酰胆碱酯酶（Hs BChE）抑制试验。两种化合物对BChE表现出明显的选择性抑制活性。