Affiliation:
1. Department of Chemistry of Bioactive Nitrogen Heterocyclic Bases V. P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry National Academy of Science of Ukraine Kyiv 02094 Ukraine
2. Department of Food Chemistry National University of Food Technologies Kyiv 01601 Ukraine
Abstract
AbstractThe efficient methods for the synthesis of pyrazole‐based aurones were developed. It was shown that reaction of benzofuran‐3(2H)‐ones with 1H‐pyrazole‐3(5)/4‐carboxaldehydes or 4‐[(dimethylamino)methylene]‐2,4‐dihydro‐3H‐pyrazol‐3‐ones led to formation of the 2‐pyrazolylmethylene‐1‐benzofuran‐3(2H)‐ones or 2‐[(3(5)‐hydroxy‐1H‐pyrazol‐4‐yl)methylene]‐1‐benzofuran‐3(2H)‐ones respectively while the reaction of 2‐[(dimethylamino)methylene]‐1‐benzofuran‐3(2H)‐ones with 1‐methyl‐5‐aminopyrazoles led to formation of 2‐[(5‐amino‐1‐methyl‐1H‐pyrazol‐4‐yl)methylene]‐1‐benzofuran‐3(2H)‐ones and 1‐methyl‐1H‐[1]benzofuro[3,2‐b]pyrazolo[4,3‐e]pyridines as minor products.