Fused pyrimidines. I. A one-step synthesis of 3-aminoisothiazolo(3,4-d)pyrimidines from 6-aminouracils and Vilsmeier reagents.
作者:YOSHIYASU FURUKAWA、OSAMU MIYASHITA、SHUNSUKE SHIMA
DOI:10.1248/cpb.24.970
日期:——
Reaction of 6-amino-1, 3-diethyluracil (Ib) with dimethylformamide-thionyl chloride afforded 5, 7-diethyl-3-dimethylaminoisothiazolo [3, 4-d] pyrimidin-4, 6 (5H, 7H)-dione (IVb) and three minor products (VIb, VIIb, VIIIb). Similar reactions of five 6-aminouracils or 6-amino-1-benzyl-cytosine (XV) with N-formyl-sec-amine-thionyl chloride afforded corresponding 3-aminoisothiazolo [3, 4-d] pyrimidine derivatives (IVa-i or XVI). When 6-amino-1, 3-diethyl-2-thiouracil (Ij) was allowed to react similarly, IVb was obtained as a major product and the yield of the expected 5, 7-diethyl-3-dimethylaminoisothiazolo-[3, 4-d] pyrimidin-4 (5H)-one-6 (7H)-thione (IVj) was very low.
6-氨基-1, 3-二乙基尿嘧啶(Ib)与二甲基甲酰胺-亚硫酰氯反应得到5, 7-二乙基-3-二甲基氨基异噻唑并[3, 4-d]嘧啶-4, 6(5H, 7H)-二酮(IVb) )和三个次要产品(VIb、VIIb、VIIIb)。五个 6-氨基尿嘧啶或 6-氨基-1-苄基-胞嘧啶 (XV) 与 N-甲酰基-仲胺-亚硫酰氯进行类似反应,得到相应的 3-氨基异噻唑并[3, 4-d]嘧啶衍生物(IVa-i 或十六)。当 6-氨基-1, 3-二乙基-2-硫尿嘧啶 (Ij) 进行类似反应时,得到 IVb 作为主要产物,并得到预期的 5, 7-二乙基-3-二甲基氨基异噻唑并-[3, 4] -d]嘧啶-4(5H)-酮-6(7H)-硫酮(IVj)非常低。