Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme? (immobilized from mucor miehei) in acetone at 50 oC for 12 h t...Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme? (immobilized from mucor miehei) in acetone at 50 oC for 12 h to give 73%, 81%, 63% yield, respectively. The products were valuable monomers for preparation of macromolecular antibiotic.展开更多
Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen perox...Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen peroxide in combination with sodium tungstate. When the same reactions were similarly performed in the absence of the catalyst, the corresponding sulfoxides could be obtained. This viable synthetic approach for the synthesis of DL-threo-thiamphenicol is a simple procedure, which has an economic advantage in view of its application for the large-scale synthesis because it can be carried out under mild conditions.展开更多
Thiamphenicol(THA) and florfenicol(FLO) aqueous solutions were irradiated to different doses by 1 MeV electron beams,and redox reactions of THA/FLO and radicals of OH,e_(eq)^- and ~·H were investigated under vari...Thiamphenicol(THA) and florfenicol(FLO) aqueous solutions were irradiated to different doses by 1 MeV electron beams,and redox reactions of THA/FLO and radicals of OH,e_(eq)^- and ~·H were investigated under various conditions.The results showed that at 8 kGy,the decomposition rate of THA and FLO was 97.2%and 98.5%, respectively.Quantitative and qualitative analysis indicated that OH played a key role in E-beam degradation of the THA and FLO in aqueous solutions,and e_(eq)^- and ~·H radicals could initiate the degradation,too.Seven primary products of the THA and FLO degradation were identified.These indicate that E-beam radiation is an effective method to reduce THA and FLO in aqueous solutions.展开更多
建立了鸡肉中3种氯霉素类抗生素残留的高效液相色谱 电喷雾电离三级四极杆质谱(HPLC ESI MS MS)测定法。该方法采用多反应监测(MRM)负离子模式,可一次对鸡肉中的氯霉素、甲砜霉素和氟甲砜霉素进行定性和定量。该方法仅需1g样品,并省去...建立了鸡肉中3种氯霉素类抗生素残留的高效液相色谱 电喷雾电离三级四极杆质谱(HPLC ESI MS MS)测定法。该方法采用多反应监测(MRM)负离子模式,可一次对鸡肉中的氯霉素、甲砜霉素和氟甲砜霉素进行定性和定量。该方法仅需1g样品,并省去固相萃取步骤,具有操作简便、有机试剂消耗量少、测定周期短等优点。方法的检出限为0 010μg/kg,测定低限为0 100μg/kg,线性范围为0 050～1 00μg/L,加标回收率为69 0%～92 8%,相对标准偏差为6 3%～12 9%。展开更多
文摘Three polymerizable vinyl thiamphenicol esters with different acyl donor carbon chain length (C4, C6, C10) were regioselectivly synthesized by Lipozyme? (immobilized from mucor miehei) in acetone at 50 oC for 12 h to give 73%, 81%, 63% yield, respectively. The products were valuable monomers for preparation of macromolecular antibiotic.
文摘Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfones in high to excellent yields via catalytic green oxidation with aqueous hydrogen peroxide in combination with sodium tungstate. When the same reactions were similarly performed in the absence of the catalyst, the corresponding sulfoxides could be obtained. This viable synthetic approach for the synthesis of DL-threo-thiamphenicol is a simple procedure, which has an economic advantage in view of its application for the large-scale synthesis because it can be carried out under mild conditions.
基金Supported by National Natural Science Foundation of China(No.40973073,40830744)Project of Leading Disciplinary Studies in Shanghai(No.S30109)+1 种基金National Key Technology R&D Program in the 11th Five-year-plan of China(No.2008BAC32B03,2009BAA24B04)Municipal Natural Science Foundation of Shanghai(No.09ZR1411300)
文摘Thiamphenicol(THA) and florfenicol(FLO) aqueous solutions were irradiated to different doses by 1 MeV electron beams,and redox reactions of THA/FLO and radicals of OH,e_(eq)^- and ~·H were investigated under various conditions.The results showed that at 8 kGy,the decomposition rate of THA and FLO was 97.2%and 98.5%, respectively.Quantitative and qualitative analysis indicated that OH played a key role in E-beam degradation of the THA and FLO in aqueous solutions,and e_(eq)^- and ~·H radicals could initiate the degradation,too.Seven primary products of the THA and FLO degradation were identified.These indicate that E-beam radiation is an effective method to reduce THA and FLO in aqueous solutions.
