Studies on pyridopyrimidines. I Synthesis of pyrazolo(3',4':4,5)pyrido(2,3-d)pyrimidine derivatives.
作者:MICHIHIKO NOGUCHI、SEIJI NAGATA、SHOJI KAJIGAESHI
DOI:10.1248/cpb.34.3994
日期:——
Pyrazolo[3', 4' : 4, 5]pyrido[2, 3-d]pyrimidine derivatives were obtained from the reaction of tosylhydrazones of 6-allylaminopyrimidine-2, 4(1H, 3H)-dione-5-carbaldehydes with lead tetraacetate in good yields. In this reaction, the nitrile imide intermediates underwent an intramolecular 1, 3-dipolar addition reaction to yield the tricyclic heterocycles. Pyrazolo[3, 4-d]pyrimido[4, 5-b]-azepine derivatives were also prepared by similar oxidation of tosylhydrazones of the corresponding 6-alkenylaminopyrimidine-2, 4(1H, 3H)-dione-5-carbaldehydes.
6-烯丙基氨基嘧啶-2,4(1H,3H)-二酮-5-羰基醛的对甲苯基肼与四乙酸铅反应得到吡唑并[3',4' : 4,5]吡啶并[2,3-d]嘧啶衍生物,收率良好。在该反应中,腈酰亚胺中间体发生了分子内 1,3-二极加成反应,生成了三环杂环。吡唑并[3,4-d]嘧啶并[4,5-b]氮杂卓衍生物也是通过相应的 6-烯基氨基嘧啶-2,4(1H,3H)-二酮-5-甲醛的对甲苯基肼的类似氧化反应制备的。