Prulifloxacin Intermediates In The Synthesis And Study

Purulifloxacin (NM441) is a bacteriophage with fluoroquinolone of the fourth class. Its chemistry name is (±)-6-fluoro-l-methyl-7-[4-(5-methyl-2-oxo-l,3-dioxol-4-yl)methyl-l-pip-erazinyl]-4-oxo-4H-[l,3]thiazeto-[3,2- ]quinoline-3-carboxylic acid. It is a good bacteriophage to Gram-positive bacteria and Gram-negative bacteria. And it doesn't cumulate in human and animal body, has less side effect and is easily absorbed. Purulifloxacin is synthesized by 4-bromomethyl-5-methyl-2-oxo-l,3-dioxole, piperazine and ethyl 6,7-difluoro-l-methyl-4-oxo-4H-[l,3]thiazeto-[3,2- ]quinoline-3-carboxylate. Piperazine is a familiar intermediate. So we research the synthesis of the other two intermediates in this paper.First, we explore the synthesize of 4-brornomethyl-5-methyl-2-oxo-l,3-dioxole. It comes from 3-hydroxy-2-butanone, which react with phosgene, in a condition of N,N-dimethylaniline as an acid-binding agent. The production shucks off hydrochloric acid with high temperature, then, bromized by N-bromosuccinimide with catalyzed by , '-azobisisobutyronitrile. The all steps are reated with yield 39.2%. We discuss the influence of reaction conditions on it such as the time of reaction, the temperature and bromide.Second, we explore the synthesize of ethyl 6,7-difluoro-l-methyl-4-oxo-4H-[l,3]thiazeto-[3,2- ]quinoline-3-carboxylate. It is synthesized from 3,4-difluoroaniline. 3,4-difluoroaniline react with carbon disulfide in existence of triethylamine, then react with ethyl chloroformate and get 3,4-difluorophenyl isothiocyanate. Followed, 3,4-difluorophenyl isothiocyanate is ethylated, cyclization, protected of hydroxy group, chloridized and shucks off hydrochloric acid and protecting group in action of sodium acetate in turn. We discuss the influence of reaction conditions on it such as the proportion of reactant, the time of reaction, the temperature, rhe acylatant and the chloridebromide and so on. This method is simple, the material is easy to get and the cost is cheap. So this technique suits to industry.