In the present paper, twelve chromenes were synthesized by coupling of 2,2,8,8‐tetramethyl‐8H‐pyrano[2,3‐f]chroman‐4‐one 1 with various aryl and benzylmagnesium chlorides. The synthetic compounds were examined for in‐vitro activity against Leishmania major, and some of them displayed efficient anti‐leishmanial activity. Among the compounds tested, compounds 9 (4‐(2‐chloro‐benzylidene)‐2,2,8,8‐tetramethyl‐3,4‐dihydro‐2H,8H‐pyrano[2,3‐f]chromene 9a and 4‐(2‐chloro‐benzyl)‐2,2,8,8‐tetramethyl‐2H,8H‐pyrano[2,3‐f]chromene 9b) were the most active with an inhibitory activity of 73.4%.

中文翻译：

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新型合成铬烯的利什曼原虫评价

在本文中，通过 2,2,8,8-四甲基-8H-吡喃并[2,3-f]色满-4-one 1 与各种芳基和苄基氯化镁的偶联合成了十二种色烯。检查合成化合物对主要利什曼原虫的体外活性，其中一些显示出有效的抗利什曼原虫活性。在测试的化合物中，化合物 9（4-（2-氯-亚苄基）-2,2,8,8-四甲基-3,4-二氢-2H,8H-吡喃并[2,3-f]色烯 9a 和 4 -(2-氯-苄基)-2,2,8,8-四甲基-2H,8H-吡喃并[2,3-f]色烯9b)的活性最高，抑制活性为73.4%。