Autor: |
Ksenia I. Kaskevich, Anastasia A. Babushkina, Vladislav V. Gurzhiy, Dmitrij M. Egorov, Nataly I. Svintsitskaya, Albina V. Dogadina |
Jazyk: |
angličtina |
Rok vydání: |
2020 |
Předmět: |
|
Zdroj: |
Beilstein Journal of Organic Chemistry, Vol 16, Iss 1, Pp 1947-1954 (2020) |
Druh dokumentu: |
article |
ISSN: |
1860-5397 |
DOI: |
10.3762/bjoc.16.161 |
Popis: |
A series of 3(2)-phosphonylated thiazolo[3,2-a]oxopyrimidines was synthesized for the first time by the reactions of chloroethynylphosphonates with unsubstituted and 5(6)-substituted 2-thiouracils. The reaction of chloroethynylphosphonates with 6-substituted 2-thiouracils bearing electron-donor groups (CH3, Ph) proceeded with high regioselectivity involving the cyclization through the N3-nitrogen atom to form new 3-phosphonylated thiazolo[3,2-a]-5-oxopyrimidines with good yield. In the case of unsubstituted and 5-methyl-2-thiouracils, cyclization occurred predominantly through the N1 atom and partially via the N3-nitrogen atom to form a mixture of the corresponding thiazolo[3,2-a]-7- and 5-oxopyrimidines. A dramatic change in the reaction regioselectivity was observed in the case of 6-trifluoromethyl-2-thiouracil that afforded 2- and 3-phosphonylated 5-oxothiazolopyrimidines in a 1:1 ratio. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
|