Microwave Synthesis And Antibacterial Activity Of The Novel Steroidal Thiosemicarbazone Derivatives

Research found that thiosemicarbazone compounds with a wide range of biologicalactivity such as: antibacterial, antiviral, antitumor, antimalarial, have been a focus forresearcher. This paper is dedicated to the green synthesis and biological activity ofthiosemicarbazone Schiff bases compounds. We use the microwave solvent-free synthetictechnology taking place of the original synthetic methods, in the synthesis and design ofhyodeoxycholic acid, chenodeoxycholic acid, deoxycholic acid with differentthiosemicarbazides reactions synthesis of Schiff base compounds. At same time, somecompounds were preliminary antibacterial activity. A series of important and innovativeachievements have been obtained.Six novel types of steroidal thiosemicarbazone derivatives have been designed andsynthesized through the microwave solvent-free technique. All seventy compoundsobtained were new and their structures were confirmed by IR,~1H NMR, ESI-MS spectraand element analyses. The effects of microwave powers, irradiation time and other factorshave been inspected. Microwave irradiation is realized a safe, convenient, efficient andeco-friendly method in synthesis of thiosemicarbazone compounds. At same time, we alsocarried out with conventional liquid solvent compared microwave method. This methodhas greatly shortened the time of production, improved significantly and more green. Ourresearch presents an important model for the preparation of these kinds of compounds inother environmental-friendly systems.Under the present experiment conditions, the antibacterial activities of somecompounds have been tested against several kinds of bacteria, such as S. aureus, B. subtilisand P. aeruginosa. Preliminary bioassay indicates that most compounds displayantibacterial to certain extent.