Electron deficient heteroaromatic ammonioamidates. Part 25. N-(Quinazolin-3-io)amidates. Part 12. The synthesis of n-(6,7-dimethoxy-2-methylquinazolin-3-io)ethoxythioformamidate and of 2-(3,4-dimethoxyphenyl)-8,9-dimethoxy-5-methyl-10bH-[1,3,4]-thiadiazolo [3,2-c] quinazoline, the ring isomer of N-(6,7-dimethoxy-2-methylquinazolin-3-io)-3,4-dimethoxy(thiobenzamidate)
作者:Magda Lempert–Sréter、Károly Lempert、Jørgen Møller
DOI:10.1039/p19830002011
日期:——
The synthesis of N-(6,7-dimethoxy-2-methylquinazolin-3-io)ethoxythioformamidate (7a) has been carried out starting with the thioacylhydrazone (5a)via cyclization of the acetylamino thioacylhydrazone (6a). An analogous attempt to synthesize the related thiobenzamidate (7b) failed and furnished instead the cyclic form of the desired product, the [1,3,4] thiadiazolo [3,2-c] quinazoline (12b). In contrast
N-(6,7-二甲氧基-2-甲基喹唑啉-3-io)乙氧基硫代甲酰胺酸酯(7a)的合成从硫代酰基hydr(5a)开始,通过乙酰氨基硫代酰基hydr(6a)的环化而进行。合成相关的硫代苯甲酰胺(7b)的类似尝试失败了,而是提供了所需产物[1,3,4]噻二唑[3,2- c ]的环状形式]喹唑啉(12b)。与硫酰hydr(5a)和(6a)相反,在研究的条件下,相关的硫代苯甲酰hydr(5b)和(6b)显示为它们的环状异构体,分别为噻二唑啉(8b)和(9b)。(9b)的环化提供了噻二唑并喹唑啉(12b)。该环状形式(12b)的存在以及喹唑啉酮(硫代氨基甲酸酯)(7b)的二聚体(17)的缺失与相关的喹唑啉碘酸盐(1)的情况形成鲜明对比。