Herein, a facile synthesis of valuable pyrido[1,2-a]pyrimidine-4-thiones is reported via novel thiocarbonylation of C(sp^(3))-H bonds with carbon disulfide(CS_(2)). This reaction features easy availability of substrat...Herein, a facile synthesis of valuable pyrido[1,2-a]pyrimidine-4-thiones is reported via novel thiocarbonylation of C(sp^(3))-H bonds with carbon disulfide(CS_(2)). This reaction features easy availability of substrates,good functional group tolerance, high yields, facile scalability and atom economy. Mechanistic investigations indicate that sulfate anion and sulfuric anhydride anion might be involved in this reaction.展开更多
Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-...Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions.This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.展开更多
An efficient method for the synthesis of novel pyrido[3＇＇,2＇＇：4＇,5＇]thieno[3＇,2＇：2,3]pyrido [4,5：d][1,3]thiazolo[3,2-a]pyrimidine-4-one derivatives（5） has been developed using a Pictet–Spengler reaction ...An efficient method for the synthesis of novel pyrido[3＇＇,2＇＇：4＇,5＇]thieno[3＇,2＇：2,3]pyrido [4,5：d][1,3]thiazolo[3,2-a]pyrimidine-4-one derivatives（5） has been developed using a Pictet–Spengler reaction between 2-（3-aminothieno[2,3-b]pyridin-2-yl）thiazolo[3,2-a] pyrimidin-5-one（3）, which could be obtained from the condensation of 7-（chloromethyl）-5H-thiazolo[3,2-a]pyrimidin-5-one（1） with3-cyanopyridine-2-thione（2） via Thorpe–Ziegler isomerization, and aromatic aldehydes under NH2SO3 H as catalysis in good yields.展开更多
基金the National Natural Science Foundation of China (No. 21822108)Sichuan Science and Technology Program (Nos.20CXTD0112, 2020YJ0491)+1 种基金National Key Research and Development Program of China (No. 2018YFC1602101)the Fundamental Research Funds for the Central Universities。
文摘Herein, a facile synthesis of valuable pyrido[1,2-a]pyrimidine-4-thiones is reported via novel thiocarbonylation of C(sp^(3))-H bonds with carbon disulfide(CS_(2)). This reaction features easy availability of substrates,good functional group tolerance, high yields, facile scalability and atom economy. Mechanistic investigations indicate that sulfate anion and sulfuric anhydride anion might be involved in this reaction.
文摘Agreen regioselective synthesis of some new and known 9-aryl-5,9-dihydropyrimido[4,5-d][l,2,4]triazolo[1,5-a]pyrimidine-6,8（4H,7H）-diones has been described via the microwave-assisted one-pot reaction of 3-amino-1H-1,2,4-triazoles,aromatic aldehydes and barbituric acids under solvent- and catalyst-free conditions.This operationally simple procedure is less laborious and provides a better scope than previously reported procedures.
文摘An efficient method for the synthesis of novel pyrido[3＇＇,2＇＇：4＇,5＇]thieno[3＇,2＇：2,3]pyrido [4,5：d][1,3]thiazolo[3,2-a]pyrimidine-4-one derivatives（5） has been developed using a Pictet–Spengler reaction between 2-（3-aminothieno[2,3-b]pyridin-2-yl）thiazolo[3,2-a] pyrimidin-5-one（3）, which could be obtained from the condensation of 7-（chloromethyl）-5H-thiazolo[3,2-a]pyrimidin-5-one（1） with3-cyanopyridine-2-thione（2） via Thorpe–Ziegler isomerization, and aromatic aldehydes under NH2SO3 H as catalysis in good yields.
