Ultrasound assisted synthesis of 4-(1H-indol-3-yl)thieno[2,3-d]pyrimidine derivatives via AcOH mediated C-C bond forming reaction

A sonochemical approach for the synthesis of 4-(1H-indol-3-yl)thieno[2,3-d]pyrimidine derivatives has been accomplished via the heteroarylation of 4-chloro thieno[2,3-d]pyrimidines with a range of indoles. The reaction was performed using AcOH as a promoter as well as solvent to give the corresponding products in good to acceptable yields. This metal free method proceeded via the C-C bond forming reaction and offers advantages such as simple conditions, shorter duration and the use of eco-friendly energy. In addition to its drawbacks, the usefulness of the methodology is presented and exemplified by the medicinal value of the compounds synthesized. The compound 3i and 3j showed good inhibition of TNF-alpha in vitro and were identified as the initial hit molecules.