The Studies On The Synthesis Of A Ketolide Cethromycin And Novel Macrolides And On The Antibacterial Activity,Structure-activity Relationships, And On The Preparing Method Of Erythromycin Cyclic 11, 12-Carbate (Davercin)

The rapid development of antibioitics -resistant strains such as MRSA MRPA PRSP VRE ESBL AMPC MBL have caused difficulty to clinical treatment in recent years. As one of common bacterial species, Streptococccus Peumoniae is growing in a trans-normal rapidity, moreover the abuse of antibioitics in clinic caused muti-drugs resistance. Bacterial community-acquired respiratory tract infections (CA-RTS) caused by resistant or muti-drugs resistant S. Peumoniae, various pattern of penicillins, amcrolides, trimethoprim—sufamethoxazole, tetracycline, furoquinolone and chloramphenicol resistant isolates is prevailing, the infections in clinical associated with β-lactam resistance in H.influenzae and M.catarrrhalis, muti-drugs resistant methiciliin -resistant Straphylococcus Aureas is also becoming a serious clinical problem. Many antibiotics or antibacterial-drugs many decrease the efficacy in a high dgree, thus, all the pharmaceutists are seeking new antibiotics which have new structure.Erythromycin as a standing macrolide antibacterial drug has notable advantages such as low consume, broad antibacterial spectrum, pharmaceutical activities and oral adminstration, has been used in clinically sine 1950s, it applys to treatment of community-acquired respiratory of the respiratory tract and skin or soft tissues infections, up to date, it remains the reference of the macrolides. Outstanding development has been obtained in macrolides of erythromycin derivatives from 1980s, some studies were carried through to decrease the side -effects and to increase the acid stability, and the bio-availability, reduce the gastrointestinal side effects, and several valuable new drugs or compounds in the practice of clinic, Rexithromycin, Clathromycin, Azithromycin and Dithromycin came into the market successfully. Since their unique therapy efficacy, research in the domain of macrolides becomes the most active point.Cethromycin (ABT-773) is a novel structure macrolide, like Telithromycin. Named ketolide for it derived from 14-memberd-ring macrolide and being characterized by a carbonyl group at the C-3 position. It inhibit bacterial protein synthesis by bang to the 50s ribosomal subunit in domain V of the 23SrRNA and causing premature dissociation...