New isochromans. 1. Synthesis and antimicrobial activity of 4‐substituted (±)‐1h‐spiro[benzo[c]pyran‐3(4H), 1′‐cyclohexane]‐1‐ones

Abstract

The reaction between homophthalic anhydride and cyclohexanone was examined both in the presence of DMAP or BF3·Et2O complex as a catalyst. The latter yielded (±)‐1‐oxo‐1H‐spiro[benzo[c]pyran‐3(4H), 1′‐cyclohexane]‐4‐carboxylic acid (3) in a higher yield (82 %). A series of new (±)‐4‐(N,N‐disubstituted‐1‐carbamoyl)‐1H‐spiro[benzo[c]pyran‐3(4H),1′‐cyclohexane]‐1‐ones (5a‐h) were synthesized from the parent acid 3 by a two‐step reaction. Differentiating microbial screening was performed for most of the synthesized compounds against twelve microorganisms belonging to different taxonomic groups. The spiro acid 3 was active against all bacterial strains with MIC ≥ 20 μg/ml against B. subtillis and P. vulgaris. E. coli was the most sensitive strain to the antibacterial effect of the tested compounds.

Synthesis, spectroscopic and structural study of trans- and cis-(±)-3-phenyl-4-(pyrrolidine-1-carbonyl)-isochroman-1-ones

“…In the first synthetic step [18], homophthalic anhydride (1) reacts with benzaldehyde to give the corresponding trans-and cis-(±)-3-phenyl-3,4-dihydroisocoumarin-4-carboxylic acids (2). It is noteworthy that the ratio among the isomers depends on the catalyst used.…”

“…[18][19][20][21]). To a suspension of cis-or trans-acid 2 in dry benzene, thionyl chloride (4 equiv.)…”

Synthesis, molecular modeling studies, and anticonvulsant evaluation of novel 1‐((2‐hydroxyethyl)(aryl)amino)‐N‐substituted cycloalkanecarboxamides and their acetate esters

“…1,1‐Disubstituted cycloalkanes were reported to display a broad spectrum of biological activities among which the anticonvulsant one and the antiepileptic one such as gabapentin as depicted in Figure .…”