Enzymatic Resolution Of Naproxen By Multiple Liquid Phase System

Naproxen is a non-steroidal anti-inflammatory drug with anti-inflammatory and analgesic effects.It has two enantiomers of R and S.The enantiomer of S configuration is 28 times more effective than that of R configuration,and the enantiomer of R configuration has side effects.Therefore,it is necessary to apply optically pure S-naproxen in clinic.The three liquid phase enzyme catalytic system(Three-Liquid-Phase System,TLPS)is a most simple multiple phase liquid phase system,as a new type of reaction system,which has many advantages.The middle phase of TLPS can be used as a "liquid immobilized enzyme" repeatedly.Enzymatic resolution of naproxen in TLPS have not been reported.In this paper,TLPSs were constructed,and we also found a lipase MAS1 from marine Streptomyces have good R configuration selectivity for naproxen.Moreover,catalytic resolution of Naproxen by two lipases with different configuration preferences in a three-phase system was studied.The main research results are as follows:Naproxen methyl ester was synthesized by chemical methylation.A suitable analytical method was established.Through preliminary screening of several lipases,a lipase AY30 with good preference for S configuration selection was found.Catalytic activity of lipase AY30 in different three-phase systems was studied.Isooctane/PEG400/sodium sulfate system was found to enhance the stereoselectivity of AY30.The effects of phase-forming substance concentration and some reaction conditions on the reaction of lipase AY30-TLPS were studied,and the variation of reaction with time was also studied.Under the optimized reaction system and conditions,the ee value of naproxen was 98.3% when the conversion of naproxen was 50%,which was obviously better than that of water-isooctane system.The excess R-isomer of the remaining reaction was regenerated by4 batches after racemization,and a yield of more than 90% was obtained.The conversion of the enzyme rich phase to the initial 80% can be achieved after 8 batches of reutilization.The microstructures of TLPS were studied.It was found that the TLPS has a unique mesophase inclusion structure.It was found that the lipase MAS1 from marine Streptomyces has good R configuration preference,and the effects of some reaction conditions on the reaction were studied.The catalytic reaction of MAS1 with R configuration preference was compared with that of a commercial lipase CALB with the same R configuration preference under the same conditions.After optimization of reaction conditions,the ee value of the unreacted S-naproxen methyl ester was more than 99% and the recovery rate was about 85% after 36 hours.Under the sameconditions,the stereoselectivity of lipase MAS1 was significantly higher than that of CALB.A three-phase system was screened to enhance the stereoselectivity of MAS1.The effects of the concentration of phase-forming substances and some reaction conditions on the reaction were studied.The variation of reaction time was also studied.Under the optimized reaction system and reaction conditions,when the conversion was 50%,the ee value of naproxen was about 80.4%,which was significantly higher than that of water-isooctane system.The conversion of the enzyme rich phase to the initial 77.6% was achieved after 8batches of reutilization.The two lipases resolution of naproxen methyl ester was carried out,and S-naproxen with an ee value greater than 99% was obtained.The result was better than that of direct resolution with AY30.