2-Amino substituted 7H-1,3,4-thiadiazolo[3,2-α]pyrimidin-7-ones 11a-e were prepared by the reaction of 2-bromo-5-amino-1,3,4-thiadiazole (1b) and diketene (8), subsequent cyclocondensation (9b → 3b) and displacement of the bromo substituents by the reaction with primary or secondary amines (3b → 11a-e). The hydrogen atom 6-H in the heterobicycle 3b is replaced by a Cl or Br atom in the transformation
通过2-溴-5-氨基-1,3,4-噻二唑的反应制备2-氨基取代的7 H -1,3,4-噻二唑并[3,2-α]嘧啶-7-酮11a-e。(1b)和双烯酮(8),随后的环缩合(9b→3b),以及通过与伯胺或仲胺的反应(3b→11a-e)置换溴取代基。在3b→14a,b的转变中,杂环2b中的氢原子6-H被Cl或Br原子取代。2-溴-6-氯化合物14a在2位与二甲胺发生化学选择性反应(14a→15)。结构阐明基于一维和二维NMR技术,包括异核NOE测量。
Lauer,R.F.; Zenchoff,G., Journal of Heterocyclic Chemistry, 1976, vol. 13, p. 291 - 293