Bazi yeni açilhomoserinlakton analoglarinin tasarimi, sentezi ve biyolojik aktiviteleri üzerinde çalişmalar

The inhibition of QS (Quorum Sensing) offers new hope in combatting multi-antibiotic resistant bacteria. Inhibiting bacterial QS systems instead of employing bactericidal or bacteriostatic strategies may find application in many different fields, such as medicine, agriculture and food technology. In a world where agricultural residues constitute a big problem, this approach can pave the way to a very soft antibacterial remedy. Also, this approach is highly attractive in terms of medicine because it does not impose harsh selective pressure on the development and emergence of resistance, from antibiotics, since QS is not directly involved in the processes essential for the growth of bacteria. Furthermore, QSI compounds are not expected to eliminate beneficial bacteria co-existing in the host. 48This study aimed to design and synthesize molecules that would be competitive inhibitors for the natural QS process of some certain bacteria.3-Acyl-2(3H)-benzoxazolone derivatives that have been synthesized by microwave assisted methods in this study, have major chemical structures such as AHL inhibitors. The structures of the compounds have been elucidated by IR, 1H-NMR, and microanalyses.The results showed that 7 of the 10 compounds which were successfully synthesized in this study, caused quorum sensing inhibition on 3 standard QS test bacteria. QSI activity for CV 12472 test bacteria was AMM38 %87, AMM40 %84, AMM39 %78, AMM37 %70, AMM44 %70, consequently in 1mg/ml concentration. QSI activity for CV VIR07 test bacteria was AMM38 %88, AMM39 %85, AMM40%83, AMM44 %75, AMM37 %75, consequently in 1mg/ml concentration. QSI activity for CV 026 test bacteria was AMM46 %88 and AMM43 %81, consequently in 1mg/ml concentration. Candidate codes AMM33, AMM34 and AMM45 due to their strong antibacterial activities were eliminated from QSI standard tests. Molecules which have antibiotic activities may cause wide damages in both membrane and chemistry of QS test bacteria which are selective just for QSI molecules.Promising results of molecular Modeling for AMM38 and AMM40 in competition with autoinducer in binding site were impressive.The tests are still being conducted to follow up on the above results and will lead us to do more extensive research. The design and evaluation of the new molecules based on these primary data will lead us to more novel, active and selective molecules.