Synthesis of Some New 6,8-Disubstituted 7,8-Dihydropyrimido[2,3:4,3]pyrazolo[1,5-a]pyrimidines and 6,7,8-Trisubstituted Pyrimido[2,3:4,3]Pyrazolo[1,5-a]Pyrimidine Derivatives
作者:Yuh-Wen Ho、Chia-Tseng Yao
DOI:10.1002/jccs.200300043
日期:2003.4
3,4-d]pyrimidine 5, which can react with appropriate Mannich base derivatives 13a-c and chalcones 27a,b to yield the corresponding 6,8-disubstituted 7,8-dihydropyrimido[2,3:4,3]pyrazolo[1,5-a]pyrimidines 15a-c and 30a,b, respectively. On the other hand, the 6,7,8-trisubstituted pyrimido[2,3:4,3]pyrazolo[1,5-a]pyrimidine derivatives 8a-g, 20a-e, 36 and 38 were obtained by treatment of compound 5 with
5-cyano-1,6-dihydro-4-methyl-2-phenyl-6-thioxopyrimidine 4 与过量 85% 的水合肼环化得到 3-amino-4-methyl-6-phenylpyrazolo[3,4-d ]嘧啶 5,可与适当的曼尼希碱衍生物 13a-c 和查耳酮 27a,b 反应生成相应的 6,8-二取代 7,8-二氢嘧啶并[2,3:4,3]吡唑并[1,5-a ]嘧啶分别为 15a-c 和 30a,b。另一方面,通过化合物处理得到6,7,8-三取代嘧啶并[2,3:4,3]吡唑并[1,5-a]嘧啶衍生物8a-g、20a-e、36和38。在酸性条件下,分别与适当的 1,3-二酮 6a-g、3-二甲基氨基-1-(取代)丙-2-烯酮 18a-e、3-氨基巴豆腈 3 和乙氧基亚甲基丙二腈 37 对图 5 进行了分析。