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231.
Through several waves of technological research and un-matched innovation strategies, bio-catalysis has been widely used at the industrial level. Because of the value of enzymes, methods for producing value-added compounds and industrially-relevant fine chemicals through biological methods have been developed. A broad spectrum of numerous biochemical pathways is catalyzed by enzymes, including enzymes that have not been identified. However, low catalytic efficacy, low stability, inhibition by non-cognate substrates, and intolerance to the harsh reaction conditions required for some chemical processes are considered as major limitations in applied bio-catalysis. Thus, the development of green catalysts with multi-catalytic features along with higher efficacy and induced stability are important for bio-catalysis. Implementation of computational science with metabolic engineering, synthetic biology, and machine learning routes offers novel alternatives for engineering novel catalysts. Here, we describe the role of synthetic biology and metabolic engineering in catalysis. Machine learning algorithms for catalysis and the choice of an algorithm for predicting protein-ligand interactions are discussed. The importance of molecular docking in predicting binding and catalytic functions is reviewed. Finally, we describe future challenges and perspectives. 相似文献
232.
Qun Zhao Jianjun Wang Tatiana Besset Xavier Pannecoucke Jean-Philippe Bouillon Thomas Poisson 《Tetrahedron》2018,74(41):6033-6040
Here we reported a Pd-catalyzed coupling reaction between acrylate derivatives and BTP (2-bromo-3,3,3-trifluoropropene) to access 3-trifluoromethylated 1,3-dienes. The reaction allows the formation of the corresponding products in good to excellent yields and moderate Z/E diastereoisomeric ratios. This method broadens the current toolbox to access 3-trifluoromethylated 1,3-dienes. 相似文献
233.
By direct synthesis route, chiral metal-organic frameworks are synthetized with enantiopure ligands or spontaneous resolution; by indirect method, post-synthetic method and chiral inductionare introduced to construct chiral metal-organic frameworks. 相似文献
234.
模糊数学在图书剔除工作中的应用 总被引:2,自引:0,他引:2
王筠 《辽宁师范大学学报(自然科学版)》1997,20(1):19-20
就图书的剔除工作给出了一种综合性的定量方法--模糊综合评判法,实践表明这是一种科学、合理、简便可行的方法。 相似文献
235.
Cristina Chamorro 《Tetrahedron》2004,60(49):11145-11157
Screening of a combinatorial CTV-based artificial, synthetic receptor library 1 {1-13, 1-13, 1-13} for binding of a variety d-Ala-d-Ala and d-Ala-d-Lac containing ligands (6-11) was carried out in phosphate buffer (0.1 N, pH=7.0). After screening and Edman sequencing, synthetic receptors were found containing amino acid sequences, which are either characteristic for binding dye labeled d-Ala-d-Ala or d-Ala-d-Lac containing ligands. For example, receptors capable of binding d-Ala-d-Ala containing ligands 6, 7, 9 and 11 contained—almost in all cases—at least one basic amino acid residue—predominantly Lys—in their arms. This was really a striking difference with the arms of the receptors capable of binding d-Ala-d-Lac containing ligands 8 and 10, which usually contained a significant number of polar amino acids (Gln and Ser), especially in ligand 8, but hardly any basic amino acids. Use of different (fluorescent) dye labels showed that the label has a profound, albeit not decisive, influence on the binding by the receptor. A hit from the screening of the CTV-library with FITC-peptidoglycan (6) was selected for resynthesis and validation. 相似文献
236.
B. Iddon O. Meth-Cohn E. F. V. Scriven H. Suschitzky P. T. Gallagher 《Angewandte Chemie (International ed. in English)》1979,18(12):900-917
Aryl- and heteroaryl-nitrenes can take part in intra-and intermolecular reactions in both of their possible electronic states (triplet and singlet). In this review we have endeavored to high-light recent synthetic uses of these reactive intermediates as well as draw attention to avenues open to further exploration in this field. Singlet arylnitrenes will interact with suitable ortho-positioned substituents to give a variety of fused azoles, some in excellent yield. In suitable solvents and in presence of amines and alcohols, phenylnitrenes undergo ring expansion to azepines which can also occur in nitrenes of certain fused bicyclic aromatics (naphthalene, quinoline, isoquinoline, benzo[b]thiophene). The latter nitrenes may also give rise to o-diamines which are useful starters for further heterocyclic synthesis. Triplet arylnitrenes (usually regarded as having only a nuisance effect in synthetic work) may also be utilized in practicable heterocyclic syntheses within a suitable molecular framework. Decomposition of aryl azides in a mixture of an organic and polyphosphoric acid leads to fused oxazoles. The mechanism is discussed for all the reactions considered. 相似文献
237.
采用液-液萃取结合GC/MS选择离子的方法,建立了人尿中8种合成麻醉镇痛剂的分析方法,讨论了回收率和检测限问题,并成功地用于实际尿样检测。 相似文献
238.
Richard C. Larock 《Angewandte Chemie (International ed. in English)》1978,17(1):27-37
Organomercurials have been known since 1850 and many synthetic routes to these compounds presently exist. The ability of these compounds to accommodate a wide variety of functional groups and to tolerate quite diverse reaction conditions makes them attractive as synthetic intermediates. While the solvomercuration-demercuration and divalent carbon transfer reactions remain the most widely used of the organomercurial reactions, a number of new synthetic procedures employing organomercurials have been developed in recent years. Many of these involve transmetallation reactions with palladium salts. 相似文献
239.
Bis‐hydrazonoyl chloride 1 reacts regioselectively with 3‐mercapto‐1,2,4‐triazole 2a , 2,3‐dihydro‐3‐thioxo‐1,2,4‐triazin‐5(4H)‐one 2b and 2‐mercaptobenzimidazole 2c to give the hitherto unknown annelated 2,3‐bis‐(phenylhydrazono)thiazoles 6a‐c , respectively. Reactions of 1 with the methylthio derivatives of such heterocycles afforded the annelated 3,3′‐bis‐(1,2,4‐triazoles) 11a‐c , respectively. Similar reaction of 1 with 2‐phenylamino‐4(3H)‐pyrimidinones 4 gave 2,3‐bis(phenylhydrazono)imidazo[1,2‐a]pyrimidin‐5(1H)‐ones 16 . Oxidation of 6c yielded the corresponding bis(phenylazo) derivative 15 . The regiochemistry of the studied reactions is discussed. 相似文献
240.