An efficient ionic liquid mediated synthesis of substituted 5H[1,3]-thiazolo[2,3-b]quinazoline-3,5-(2H)-dione and 5H-thiazolo[2,3-b]quinazolin-5-one

作者：Yadav Ashok K^*; Dhakad Pankaj; Sharma Gopi Ram

来源：Tetrahedron Letters, 2013, 54(45): 6061-6063.

DOI：10.1016/j.tetlet.2013.08.090

• Quinazolinethiones
• Thiazoloquinazolinone
• Thiazoloquinazolindione
• Ionic liquid

A new, environmentally benign two-step synthesis of 5H[1,3]-thiazolo[2,3-b]quinazoline-3,5-(2H)-dione and 5H-thiazolo[2,3-b]quinazolin-5-one derivatives has been accomplished stepwise. The substituted 2-aminobenzoic acid upon condensation with thiourea in 1-buty1-3-methylimidazolium bromide at moderate temperature under nitrogen atmosphere yielded 2-thioxo-1H-4-quinazolinones. The resulting intermediate 2-thioxo-1H-4-quinazolinones, when reacted with 2-chloroethanoic acid/2-chloropropanal underwent cyclization to yield the desired product in excellent yields.

• 出版日期2013-11-6