[1, 2, 5] Thiadiazolo [3, 4d] pyrimidines have been synthesized from 4, 5-diaminopyrimidines and N-sulfinylaniline. An intermediate in this reaction has been isolated. Replacement reactions have been observed to occur readily at position 7, and reductive cleavage of the thiadiazole ring has been demonstrated. Similarities in the properties of [1, 2, 5] thiadiazolo- [3, 4d] pyrimidines and pteridines have been noted. the pteridine^.^ Schrage and ...
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![[1,2,5]Thiadiazolo[3,4-d]pyrimidine-7(3H)-thione结构式](https://image.chemsrc.com/caspic/166/89797-62-6.png)
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![[1,2,5]Thiadiazolo[3,4-d]pyrimidine,7-(4-morpholinyl)结构式](https://image.chemsrc.com/caspic/083/6313-27-5.png)
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![[1,2,5]Thiadiazolo[3,4-d]pyrimidin-7-amine, N-phenyl结构式](https://image.chemsrc.com/caspic/060/6306-88-3.png)
![[1,2,5]thiadiazolo[3,4-d]pyrimidin-7-amine结构式](https://image.chemsrc.com/caspic/385/2829-57-4.png)
![3-sulfanylidene-8-thia-2,4,7,9-tetrazabicyclo[4.3.0]nona-1,6-dien-5-one结构式](https://image.chemsrc.com/caspic/174/6306-85-0.png)
![N,N-dimethyl-8-thia-2,4,7,9-tetrazabicyclo[4.3.0]nona-2,4,6,9-tetraen-5-amine结构式](https://image.chemsrc.com/caspic/136/6306-86-1.png)