Tetrahydropyridopyrimidines (THPPm) 1–3 underwent tandem cleavage–cyclization piperidine ring enlargement under the action of terminal activated alkynes to produce tetrahydropyrimido[4,5-d]azocines 4–7 in good preparative yields. The latter compounds are representatives of a new heterocyclic system.
Tetrahydropyridopyrimidines(THPPm)1 - 3后行串联切割环化终端而激活炔以产生四氢
嘧啶并[4,5-的作用下
哌啶环放大d ] azocines 4 - 7中制备好的产率。后一种化合物是新杂环系统的代表。