乙酯基

ABSTRACT Immobilized penicillin acylase (from E.coli) was used to catalyze 7 phenylacetamido 3 E propenyl cephalosporanic acid hydrolyzation into 7 amino 3 E propenyl cephalosporanic acid. Then, trans APRA was acylated with hydroxyethyl ester of 4 hydroxy D phenylglycine to obtain trans cefprozil.

以7 苯乙酰氨基 3 E 丙烯基 3 头孢菌素 4 羧酸为原料，在青霉素酰化酶作用下，首先酶法水解得到3 E 丙烯基 3 头孢菌素 4 羧酸，过滤固相酶，滤液调pH分离得到反式APRA固体；在青霉素酰化酶作用下，反式APRA再与对羟基苯甘氨酸乙二醇酯缩合，得到反式头孢丙烯；酶法合成所得的产品与进口反式头孢丙烯对照品一致。

Analytical results showed that the upper clear liquid of pyrolysis oils was mainly consisted of water-soluble substances,such as phenol,cresol,xylenol,sugars,hydantoins,morpholines,pyranones and pyridine derivatives compounds,etc.,while the lower sediment was mainly insoluble or hardly water-soluble substances,such as the big substituent phenolics(the number of substituent carbon atoms of which is greater than or equal to 2),aryl phosphate esters,fatty acid esters and nitrile compounds,and so on.

研究表明，热解油上层清液主要是一些较易溶于水的物质，如苯酚、甲酚、二甲酚、糖类、乙内酰脲类、吗啉类、吡喃酮类和吡啶类化合物等；而下层沉淀则主要为不溶或难溶于水的物质，如大取代基酚类（取代基碳原子数≥2）、磷酸三芳基酯类、脂肪酸酯类和腈类化合物等。

Two kinds of ashless and non-phosphorus additives, hydroxyl-containing dithiocarbamate derivatives were prepared.

合成了2-乙羟基-吗啡啉二硫代氨基甲酸酯和2-乙羟基-二正丁胺基二硫代氨基甲酸酯两种添加剂。

Objective To evaluate the biocompatibility of poly (lactic acid/glycolic acid/asparagic acid-co-polyethylene glycol) tri-block copolymer in vitro.

目的 对自主研制的三嵌段骨基质材料－聚丙交酯／乙交酯／天冬氨酸－聚乙二醇的体外生物相容性进行评价。

Study on an efficient process for the preparation of trifloxystrobin starting from 2-methylacetophenone bypartial oxidation,esterification,reaction with methoxyamine,bromization and condensation with 3'- acetophenone oxime.

以邻甲基苯乙酮为原料，经过高锰酸钾的碱性氧化，甲醇酯化，再与甲氧基胺盐酸盐肟化后，用N-溴丁二酰亚胺溴化，最后和间三氟甲基苯乙酮肟缩合得到目标产物肟菌酯。

The first asymmetric synthesis of trans-β-hydroxy-γ-butyrolactones:-(3R, 4R, 5S)-4-(1-acetoxy-isopropyl)-3-hydroxy-butyrolactone 65a was achieved starting from isobutylaldehyde through nine steps. The key steps involve the construction of three chiral carbon centers by the Sharpless's asymmetric epoxidation and Substrate directable chemical reaction.

以异丁醛为起始原料，经过九步反应首次设计合成了具有三个手性中心的trans-β-羟基-γ-丁内酯：-（3R，4〓，5S）-4-（1-乙酰氧基-异丙基）-3-羟基-丁内酯65a，关键步骤是Sharpless不对称环氧化和底物定向不对称合成反应。

Attempts in part I of the dissertation were to develop microemulsion systems using medium chain triglyceride, Captex 300, deionized water (H2O), and TPGS as surfactant for the oral delivery of protein drugs or poorly water soluble drugs. Pseudo-ternary phase diagrams were constructed to elucidate the phase behavior of systems composed of medium-chain triglyceride and water with TPGS as main surfactant, polysorbates (Tween 20, Tween 40, Tween 60 and Tween 80) as adjuvant surfactants, and polyethylene glycols (PEG 400 and PEG 600) and polyols (ethanediol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol and glycerin) as cosurfactants.

藉由拟三相图（Pseudo-ternary Phase Diagrams）的建立来了解中链型三酸甘油酯、去离子水及TPGS为主要界面活性剂配合聚醇山梨酯（如Tween 20、Tween 40、Tween 60及Tween 80）为辅助界面活性剂或聚乙二醇（如PEG 400及PEG 600）及多醇类（如乙二醇、1，2-丙二醇、1，3-丙二醇、1，3-丁二醇、1，4-丁二醇及甘油作为共界面活性剂所形成的微乳基剂之相变化。

In this paper, the glyoxal structure both in reagent and in bulking solution were detected by infrared spectro and mass spectra, the result shows that there is no aldehyde group but only hydrate existing in both solutions. Besides, the mechanism of the ac-tion between glyoxal and waterlogged wood is discussed and some problems like how to prevent the bulk-ing solution from acidification are also mentioned.

此外，还运用红外光谱和质谱法测定了试剂乙二醛和加固液的结构，详细讨论了乙二酯在试剂和加固液中官能团的存在形式和聚合状态的细微变化，指出在二种溶液中并不存在醛基，乙二醛仅以水合物的形式存在并讨论了乙二醛与饱水古木的作用机理，提出用醇溶液能有效控制乙二醛使用中易返酸等问题。

A second group includes those compositions, which include an organic polymeric binding material, eg, mixed cellulose esters of monobasic or dibasic acids such as cellulose acetate succinate; an addition-polymerizable ethylenically unsaturated compound, eg, vinylidene and vinyl monomers, preferably of the acrylic or alkacrylic ester type; eg, triethylene glycol diacrylate; and an addition-polymerization initiator which forms radicals under the influence of actinic radiation, eg, anthraquinone.

第二组包括那些作品，其中包括有机聚合物具有约束力的物质，例如，对一元或二元酸混合纤维素酯，如醋酸纤维素琥珀酸； 1此外，聚合ethylenically不饱和化合物，例如，偏和乙烯基单体，丙烯酸最好的或alkacrylic酯类型，如，三乙二醇二丙烯酸酯；和加成聚合引发剂的形式下光化辐射的影响自由基，例如，蒽醌。

Bezaldehyde was used as protective agent in first method.S-Epichloeohydrin was aminated and acidulated to give(2S)-1-Amino-3-chloro-propanol Salts.The acetylation of (2S)-1-Amino-3-chloro-propanol by acetic anhydride produced the intermediate-N-[2--3-chloropropyl]acetamide.And then at 20℃,in the presence of lithium tert-butoxide,benzyl 3-fluoro-4-morpholinophenyl carbamate react with-N-[2--3-chloropropyl]acetamide to give linezolid in total yield of 43.6%.

路线一采用苯甲醛作保护剂，使S-环氧氯丙烷氨解、酸化生成S-1-氨基-3-氯-2-丙醇盐酸盐，然后经乙酰化反应后，生成中间体-N-[2-乙酰氧基-3-氯丙基]乙酰胺，再用N-(3-氟-4-吗啉苯基)氨基甲酸苄酯和中间体在催化剂叔丁醇锂存在下25℃反应生成利奈唑酮，总产率达到43.6%。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。