XXIV—The thio-analogues of coumarin and its derivatives

Zeolite‐promoted Synthesis of Coumarins and Thiocoumarins

“…In 1,2-dichloroethane at 85°C during a short time (1 h), the starting ester 1 b did not evolve without promoter (entry 1), while in the presence of promoter, it was more or less converted to the expected coumarin 2 b, but with very variable conversions and yields depending on the promoter nature (entries [2][3][4][5][6][7][8][9][10][11][12][13][14]. Under these conditions, typical Lewis acids led to the expected coumarin 2 b, but with a poor efficiency, as only around one third of the starting ester was converted and only half of it as the expected coumarin 2 b (entries [12][13].…”

“…[7] In contrast, the non-natural thiocoumarins are far less represented, although their synthesis could be traced back to 1912. [8] Together with coumarins, they have been developed as low nanomolar selective inhibitors of zinc metalloenzyme carbonic anhydrase, [9] as inhibitors of cell adhesion and of lipid peroxidation. [10] They also have been used as chemodosimeters, highly selective toward Hg 2 + or Au 3 + ions due to chromo-and fluorogenic changes in the presence of these ions.…”

“…In contrast, the non‐natural thiocoumarins are far less represented, although their synthesis could be traced back to 1912 . Together with coumarins, they have been developed as low nanomolar selective inhibitors of zinc metalloenzyme carbonic anhydrase, as inhibitors of cell adhesion and of lipid peroxidation .…”