Preparation and characterization of cyclic-ketone derivatives of methyl undec-10- enoate and their cyclocondensation with mercaptoacetic acid

Reaction of methyl undec-10-enoate 2 with cyclopentanone 1a affords two products, methyl 2-(2′-cyclopentanonyl)undec-10-enoate 3a and methyl 11-(2′-cyclopentanonyl)undecanoate 4a. Similarly, the reaction of cyclohexanone 1b gives two products 3b and 4b. Compounds 4a and 4b on further reaction with mercaptoacetic acid and ammonium carbonate yield the products 5a and 5b, respectively. Products have been characterized by elemental analysis and spectral data. Compounds 3a, b, 4a, b and 5a,b have been tested for antimicrobial activity. The compounds 3a,b and 4a,b show negative results at 100 μg/mL whereas the compounds 5a,b show positive results at 100 μg/mL.