酶法合成头孢克罗

Enzymatic synthesis of cefaclor from 7-aminodesacetoxymethyl-3-chlorocephalosporainc acid(6-ACCA) and phenylglycine derivatives using penicillin G acylase was studied .Many factors that affect the conversion of 7-ACCA to cefaclor were examined.The immobilized enzyme from Bacillis megaterium gave a better catalytic properties and the higher conversion was obtained using phenylglycine methyl ester(PGME) as acyl donor.And the external mass transfer limitation could be eliminated when the stirring rate was more than 150r/min.Low temperature was beneficial for the synthesis and the results showed that the synthetase activity was hardly influenced by temperature while the amidase activity was affected greatly by temperature.The optimum reaction conditions were determined at pH 6.5 and 10℃,respectively.The best 7-ACCA conversion of 56% was achieved when the intial concentration of 7-ACCA and PGME was at 50 mM and 150mM,respectively.     

头孢卡品酯的合成

头孢卡品酯是第四代头孢菌素中的重要品种,具有稳定性高、抗菌能力强、毒性低等特点,其合成方法已有很多研究报道。本文以7-氨基头孢氨酸(7ACA)和(Z)-2-(2-叔丁氧羰基氨基噻唑-5-基)-2-戊烯酸为原料设计并研究了4条头孢卡品酯的合成路线,最终通过路线IV成功地合成了头孢卡品酯,总收率达到14%。     

2-(2-氯乙氧基)乙酸酯的合成及性质

在探索 2 氧代 1 ,4 二氧六环应用的实验中 ,我们发现利用 2 氧代 1 ,4 二氧六环与氯化亚砜及一些低碳醇反应 ,可以使 2 氧代 1 ,4 二氧六环发生开环反应 ,生成一类新的有机氯代醚酯类化合物——— 2 ( 2 氯乙氧基 )乙酸酯。其中 ,Ｒ分别为甲基、乙基、丙基、异丙基、丁基和仲丁基。该类化合物在酸性、碱性条件下水解 ,可以得到不同的产物。由于 2 氧代 1 ,4 二氧六环可由一缩二乙二醇经催化脱氢得到[1 ] ,而一缩二乙二醇又是工业上制备乙二醇的副产物。因而开展有关 2 ( 2 氯乙氧基 )乙酸酯的合成及性质方面的研究可为一缩二乙二…     

一类新型含噻吩环西夫碱的合成

通过4，4，4-三氟-1-(2-噻吩基)-1，3-丁二酮与一系列氨基化合物缩合合成了一类新型含噻吩环的西夫碱。其组成与结构经元素分析，IR，1HRNMR和MS进行了表征。     

DL—β—（噻唑基）—α—乙酰氨基丙酸合成方法的改进

报道了由（４－噻唑基）－甲基乙酰氨基丙二酸二乙酯通过碱性水解并脱羧来合成外消旋β－（４－噻唑基）－α－乙酰氨基丙酸的新路线，产率可达８０％，同时对前几步中间产物的合成进行了有效的改进。     

2-(E-2-苯乙烯基)喹啉的合成

以苯甲醛为原料在碱性条件下与丙酮缩合得苄叉丙酮（1），1与邻氨基苯甲醛发生Friedlaender缩合反应得到新的目标产物2－（E－2－苯乙烯基）喹啉(2),产率81％。     

DL-β-(4-噻唑基)-α-乙酰氨基丙酸含成方法的改进

报道了由（４－噻唑基）－甲基乙酰氨基雨二酸二乙酯通过碱性水解并脱羧来合成外消旋β－（４－噻唑基）－α－乙酰氨基丙酸的新路线，产率可达８０％，同时对前几步中间产物的合成进行了有效的改进。     

2,5-二(2-氨基乙氧甲基)噻吩合成及抑菌活性

噻吩烷基胺及其衍生物对疟疾、麻风、真菌、病毒和某些肿瘤均有较强的药理活性[1～ 2 ] ,因此合成和开发这类新物质具有重要的意义。以前 ,由 2 噻吩甲醛合成的噻吩类衍生物药物较多[3] ,但对噻吩双取代衍生物的合成研究还未引起重视。因此 ,为了探索这类化合物的性质和抑菌效果。我们合成了未见文献报道的 2 ,5 二 ( 2 氨基乙氧甲基 )噻吩 ,通过多种测试手段 ,确定了它的组成结构 ,其合成路线如下 :1　实验部分1 1　仪器与试剂Ｎｉｃｏｌｅｔ1 70Ｓ红外光谱仪 (ＫＢｒ压片 ) ,ＰＥ 2 4 0Ｃ型元素分析仪 ,ＥＭ 360 60ＭＨｚ核磁共振仪。…     

The Synthesis of a Novel Lignan

Lignans have attracted much interest over the years on account of their widespread ocurrence in nature1, and on account of their broad range of biological activity2. Thus, several lignans are known to exhibit anti-tumor activity3-7, while others function as growth inhibitors and antifungal agents8,9. The importance is the isolation of lignans from animals, including human beings10-12, which has led to the suggestion that such compounds may be an example of a novel class of hormone controlling …     

Influence of Organic Matter on the Sorption of Cefdinir,Memantine and Praziquantel on Different Soil and Sediment Samples

Pharmaceuticals are known for their great effects and applications in the treatment and suppression of various diseases in human and veterinary medicine. The development and modernization of science and technologies have led to a constant increase in the production and consumption of various classes of pharmaceuticals, so they pose a threat to the environment, which can be subjected to the sorption process on the solid phase. The efficiency of sorption is determined by various parameters, of which the physicochemical properties of the compound and the sorbent are very important. One of these parameters that determine pharmaceutical mobility in soil or sediment is the soil–water partition coefficient normalized to organic carbon (K_oc), whose determination was the purpose of this study. The influence of organic matter, suspended in an aqueous solution of pharmaceutical (more precisely: cefdinir, memantine, and praziquantel), was studied for five different types of soil and sediment samples from Croatia. The linear, Freundlich, and Dubinin–Raduskevich sorption isotherms were used to determine specific constants such as the partition coefficient K_d, which directly describes the strength of sorbate and sorbent binding. The linear model proved to be the best with the highest correlation coefficients, R² > 0.99. For all three pharmaceuticals, a positive correlation between sorption affinity described by K_d and K_oc and the amount of organic matter was demonstrated.     

非催化条件下合成尿囊素

以尿素和乙醛酸为原料,在无催化剂存在的条件下,合成了尿囊素。优化反应条件为:乙醛酸30 mmol,n(乙醛酸)∶n(尿素)=1.0∶3.0,于60℃反应3 h,产率60.3%,纯度98.0%。     

糖基化青蒿素衍生物的合成

以糖[D-葡萄糖(1a),D-木糖(1b),D-甘露糖(1c),乳糖(1d)和D-半乳糖(1e)]为原料,经溴化、乙酰化一锅法使糖基乙酰化制得相应的溴代乙酰化糖(2a～2e);2在相转移催化剂四丁基硫酸氢铵催化下分别与二氢青蒿素经醚化反应合成了五个糖基化青蒿素衍生物,其结构进行1H NMR,13C NMR,IR和LC-MS表征。     

丙烯酸五氟苯酚酯的合成

丙烯酸五氟苯酚酯单体是重要的精细化工原料和中间体,其卤素官能团的存在有利于聚合物的改性加工,广泛应用于生物广谱杀虫剂、防污涂料以及各种光学材料聚合物等领域~([1-5]).     

4种氮杂双环化合物的合成方法改进

以邻苯二胺及2,3-二氨基吡啶为原料,与羰基化合物反应制备苯并吡嗪、吡啶并吡嗪、苯并咪唑和吡啶并咪唑4种氮杂双环化合物,探讨了溶剂、温度、时间和pH值等实验条件对反应的影响。 在合成吡啶并吡嗪时,采用正丙醇为溶剂,用甲醇钠调节pH=9,回流反应1 h,将收率从35.7%提高至89.4%;在合成苯并吡嗪时,用水作溶剂,用亚硫酸钠调节pH=9,60 ℃反应40 min,产物纯化采用低温静置代替减压蒸馏,收率可提高至98.3%;尝试不同方法合成苯并咪唑和吡啶并咪唑,确定最优合成条件分别为：邻苯二胺在88%的甲酸溶液中回流2 h,苯并咪唑收率为92%;2,3-二氨基吡啶在原甲酸三已酯中回流3 h,加浓盐酸继续回流1 h,吡啶并咪唑收率为84.2%。     

一种新型α-甲醚基吡咯的合成

以乙酰乙酸苄酯(4)为原料, 经Knorr缩合制备了2,4-二甲基-3-丙酸甲酯基-5-羧酸苄酯基-1-氢吡咯 (2) 和2,4-二甲基-3-羧酸甲酯基-5-羧酸苄酯基-1-氢吡咯(3)。乙醚介质中,溴水氧化条件下,吡咯 (2) 发生自身缩合生成二吡咯甲烷 (7),吡咯 (3)无反应发生。在Pb(OAC)₄氧化条件下,当其浓度为吡咯 (3)浓度的2倍时,在80 ℃,吡咯 (3) 完全转华。所得产物经HCl甲醇溶液回流,以82%的产率制备了新型2-甲氧基甲基-3-羧酸甲酯基-4-甲基-5-羧酸苄酯基-1氢吡咯 (1)。吡咯(1)、(2)、(3)及二吡咯(7)的结构用核磁、元素分析、质谱和红外等测试技术进行了表征。吡咯(1)的构建对进一步研究吡咯构效关系具有一定参考价值。     

丹参素衍生物的合成

以取代苯甲醛为原料,经达参缩合、还原、水解反应合成了24个丹参素衍生物,其结构经1H NMR和MS表征。有7个是新化合物。     

1，1-双二茂铁基烷的合成与表征

1;1-双二茂铁基烷的合成与表征;缩合;双二茂铁基烷;合成;表征