Synthesis and antimicrobial activity of heterocyclic ionone-like derivatives

A number of heterocyclic ionone-like derivatives 5 were prepared with appropriate bifunctional reagents by one-pot cyclisation of 3-dimethylamino-5-(2,6,6-trimethyl-2-cyclohexen-1-yl)-2,4-pentadienal 3a, which was, in turn, obtained from alpha-ionone with N,N-dimethylformamide/phosphorus oxychloride. All compounds 5 possess remarkable activity against the selected Gram-positive, Gramnegative bacterial strains and against Candida albicans. Derivatives 5a2 and 5a6, acting at a high level especially against both Propionibacterium acnes and Staphylococcus aureus, could play a potential role in the treatment of acne and related skin disorders. (C) 1999 Editions scientifiques et medicales Elsevier SAS.