AM1 theoretical study, synthesis and biological evaluation of some benzofuran analogues of anti-inflammatory arylalkanoic acids.

Using the semi-empirical quantum-mechanical method AM1, the molecular geometries of the arylalkanoic acids, indomethacin, naproxen and ibuprofen, were optimized and their frontier orbital charge distributions evaluated. Then, these molecular parameters were compared in order to identify structure-activity relationships and, on the basis of these, four benzofuran-3-acetic acids were designed as potential non-steroidal anti-inflammatory agents, and rapidly synthesized by a novel and easily generalized route. Notwithstanding the structural similarities between the synthesized compounds and the anti-inflammatory arylalkanoic acids, these compounds did not appreciably inhibit human platelet cyclooxygenase in vitro.