substitution reactions of alkyl halides

... using the purified recombinant protein, the conversion of reagents and products of the exopeptidasecatalyzed hydrolysis of Met1 and cyclization of Gln1 to pyroglutamyl were monitored at different ... of saturated sinapinic acid in the same solvent of the matrix, and 0.5 lL of the mixture was immediately applied to a sample probe spot Protein expression Cyclization reaction as a function of ... and expressing it as the fraction of hydrolyzed (Met1)-ONC (M23L) Figure shows the results of the characterization of the hydrolysis reaction as a function of guanidinium chloride concentration...

Ngày tải lên: 19/02/2014, 12:20

... addition of a solution of 1,2-ethylendiamine monohydrate in ether to a solution of HAuCl4 in ether; the yellow precipitate was dissolved in water giving an orange solution A white precipitate of [Au(en)2]Cl3 ... stoichiometric excess of cyanide The UV-Vis spectra were recorded before and immediately after the addition of a concentrated solution of sodium cyanide Reaction with imidazole The interaction of [Au(bipyc-H)(OH)][PF6] ... [Au(bipyc-H)(OH)][PF6] Further information on the reactions of gold(III) complexes with BSA was gained by the application of classical biochemical separation techniques The main goal of these experiments was to provide...

Ngày tải lên: 07/03/2014, 21:20

... Furthermore, a prediction of the secondary structure of TK1 [30–32] places Val106 in the middle of an a-helix which aligns in CLUSTAL [33] with one of the interface helices (a-helix 4) of HSV1TK This may ... and V106T We then characterized the enzymatic properties of the mutant enzymes The apparent native sizes of the –ATP forms of V106WT and of the mutant recombinant enzymes (subunit size 24 kDa, ... were eluted essentially as V106WT: a substantial part of each of these enzymes was Fig Gel filtration of rLy-TK166)136 proteins About 100 lg of rLyTK166)136(Val106) (d) and rLy-TK166)136(Met106)...

Ngày tải lên: 16/03/2014, 16:20

... of DABIA-alkylated cysteines at 436 nm (Fig 2) The nature of the inhibitory effect exerted by DABIA was studied in detail The possibility that DABIA inhibition is the result of the reaction of ... for the inactivation of DABIA was 168 M)1Æmin)1, as determined from the slope of this plot In an effort to demonstrate that DABIA is bound to sulfhydryl groups of SSADH, lM of SSADH was incubated ... extinction coefficient of 29 000 M)1Æcm)1 at 436 nm DABIA gave overall incorporation values of about 7.5 mol per enzyme tetramer, indicating that mols of sulfhydryl groups of SSADH were masked...

Ngày tải lên: 16/03/2014, 18:20

... aimed at an elucidation of a detailed molecular picture of the light-driven DNA repair process Results Construction of a DNA photolyase E109A mutant MTHF, the second cofactor of E coli DNA photolyase, ... photolyase to a level of about 15% of total cell protein Purification by published procedures afforded the blue radical form of the mutant enzyme The yield of isolated protein was about twofold higher ... disappeared A more detailed assessment of the impact of 15N substitution is possible by inspection of the double difference in trace E which is obtained by subtraction of trace B from trace A in Fig...

Ngày tải lên: 16/03/2014, 18:20

... reaction with the alkyne, at a range of concentrations, in the presence of NADH (100 lm) The decay of enzyme activity as a function of 2667 Adventitious reactions of alkene monooxygenase time was ... activity was measured as a function of the time between the start of the reaction (addition of NADH) and removal of the alkyne by flushing with nitrogen First-order decay of enzyme activity was observed, ... underestimated The positive deviation of the latest data points from the extrapolated linear 2663 Adventitious reactions of alkene monooxygenase Fig Kinetics of inactivation of AMO by (A) propyne and (B)...

Ngày tải lên: 16/03/2014, 19:20

... potential of CO2† – , the radical catalyzes reduction of Fe(III) [12] and reductive dehalogenation of recalcitrant aromatic halides [31] O2† – catalyzes oxidation of Mn(II) and reduction of Fe(III) ... products of pentafluorobenzyl oxime [26] (data not shown) The reactions of MnP in four different buffers clearly demonstrate that the formation of glyoxal was significantly stimulated by the presence of ... linoleic Fig Mass chromatograms of PFBO derivatives of products of lipid peroxidation by C subvermipora MnP and soybean lipoxygenase at m/z 181 (A) Products of the oxidation of linoleic acid by MnP in...

Ngày tải lên: 24/03/2014, 04:21

... OF INDUSTRIAL CATALYSTS Lawrie Lloyd METAL-CATALYSED REACTIONS OF HYDROCARBONS Geoffrey C Bond METAL–OXYGEN CLUSTERS: The Surface and Catalytic Properties of Heteropoly Oxometalates John B Moffat ... 598 599 599 601 CONTENTS 14.2.3 Reactions of Linear Alkanes with Hydrogen 14.2.4 Reactions of Branched Alkanes with Hydrogen 14.2.5 Reactions of Cyclic Alkanes with Hydrogen ... heating of a wire of the catalytic metal, or of a fragment of the metal attached to an inert wire, in an evacuated vessel, atoms of the metal evaporated and then condensed on the walls of the...

Ngày tải lên: 01/04/2014, 10:35

... PREPARATION OF ALKYL HALIDES Alkyl halides from alcohols Only in acidic conditions Alkyl halides from alkenes More stable Alkyl halides from alkanes Chlorination is much less selective REACTIONS OF ALKYL ... interconversions of 1o & 2o alkyl halides Elimination reactions will occur for 3o alkyl halides 10 Elimination reactions will occur for 3o alkyl halides 11 Williamson ether synthesis 12 Nucleophilic substitutions ... Chapter 9: ALKYL HALIDES NOMENCLATURE OF ALKYL HALIDES Common names: alkylhalide (chloride, bromide…) IUPAC names: halogeno + alkane (chloro, bromo…) Alkyl & halogen substituents are considered of equal...

Ngày tải lên: 04/07/2014, 15:20

... both of them were inseparable It so happened that a student from Primary Six needed to be chosen as the assistant secretary of the school’s sports department She was to represent the students of ... four, five and six at any meeting held in preparation of the school’s coming sports meet The teachers had unanimously chosen Diana because of her popularity among the other students Besides, she ... mention of her name made her strain her neck and try to catch a few words from their conversation What a shock she had when she finally pieced the information together Liza was actually jealous of...

Ngày tải lên: 22/07/2014, 03:21

... gives a summary of the production and disposal emissions as well as of the substitution effects of an increased use of wood of 0.81 Mio m3/year 3.3 Energetic substitution effects The substitution ... with product emissions of around 18% of the total effect of an increased use of wood in Switzerland If one considers the effect of an increased use of wood in the mirror of the reduction commitment ... C-pool and substitution effects of wood products 895 Figure Substitution effects of different wood products due to an increased use of wood, in Switzerland (CH) and abroad (+ 0.81 Mio m3 of wood)...

Ngày tải lên: 08/08/2014, 00:22

... be concluded that the use of live attenuated vaccine of RVF (Smithburn strain) for immunization of live stock in Egypt is danger As the use of live attenuated vaccine of RVF (Smithburn strain) ... degeneration of hepatocytes showing kid Liver of in group-1, animal sacrificed two weeks P.V., Liver of kid in group-1, animal sacrificed two weeks P.V., showing diffuse vacuolar degeneration of hepatocytes ... disconfiguration of the hepatic parenchyma was seen Some bile ducts showed hyperplasia of the epithelial lining Large number of mononuclear cells infiltration was Figure hyperplasia of animal sacrificed...

Ngày tải lên: 12/08/2014, 04:21

Ngày tải lên: 13/11/2014, 16:04

... 1.4.3.1 Reactions of halogens 31 1.4.3.2 Reactions of hydrogen halides 32 Reactions of gaseous oxides 32 1.4.4.1 33 1.4.3 1.4.4 Reactions of ... image of Ge(100) 1.4.3 Reactions of halogens and halides Reactions of halogens on semiconductor surfaces are of both fundamental and industrial interest In semiconductor industry, reaction of halogens ... 1.3.4 Reactions of multifunctional molecules After the basic principles of monofunctional organic molecules reactions on Ge(100) were well established, further interests were extended to reactions...

Ngày tải lên: 08/09/2015, 22:20

... Table of Contents Summary List of Tables List of Schemes List of Figures List of Abbreviations List of Publications Chapter Introduction 1.1 1.1.1 Introduction 1.1.2 Historical background of organocatalysis ... Derivatizations of the vinylogous aldol adducts 57 2.4.4.1 Preparation of lactone 57 2.4.4.2 Preparation of glycerol derivatives 60 2.4.4.3 Preparation of antifungal agent 62 2.4.5 Analytical data of products ... direct Michael addition of bicyclic -ketoesters to aryl nitroolefins List of Schemes Scheme 1.1 Structures of some representative ligands Scheme 1.2 Early examples of asymmetric reactions using organic...

Ngày tải lên: 10/09/2015, 08:24

... DIELS–ALDER REACTIONS OF ANTHRONES SHEN JUAN 2008 CHIRAL BICYCLIC GUANIDINE CATALYZED DIELS–ALDER REACTIONS OF ANTHRONES SHEN JUAN (BSc., Suzhou University) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF ... of (+)-epiepoformin and (–)-theobroxide Scheme 2.8 Base-catalyzed reactions of N-tosyl-3-hydroxy-2-pyrone Scheme 2.9 Synthetic route of three validamine type compounds Scheme 2.10 Synthesis of ... constants of Et3N catalyzed Diels–Alder reaction of Anthrone Table 3.2 Order of Et3N Table 3.3 VT-NMR Experiments of Et3N catalyzed Diels–Alder reaction of Anthrone Table 3.4 Kinetic study of chiral...

Ngày tải lên: 12/09/2015, 10:17

... catalyze the Diels-Alder reactions of 3-hydroxy-2-pyrone and electron deficient dienophiles giving cycloadducts in good yields.9 The use of the base varied from a catalytic amount of 0.1 equivalent ... The methods whereby DA reactions are traditionally and conventionally carried out included reflux and the use of Lewis acids as catalysts.2 On the other hand, the use of BrØnsted bases as catalysts ... Chapter 1.1 BrØnsted-Base Catalyzed Diels-Alder Reactions The Diels-Alder (DA) reaction is unarguably one of the most powerful bond forming reactions in organic chemistry as it creates as many...

Ngày tải lên: 14/09/2015, 08:47

... DMSO 0.5 99 All entries employed eq of 1, eq of 4-cyano benzaldehyde, 0.15 eq of TBD and 0.5 ml of solvent 34 Chapter With optimized conditions, the VARs of 3-hydroxy-2-pyrone were attempted ... Scheme 2.22 Protection of one hydroxy group of VAP with a tosyl group 37 Chapter Figure 2.8 Crystal structure of VAP 10 The crystal structure of VAP 10 indicated a γ-attack of the pyrone on the ... reactions However, a large part of 2-pyrone chemistry also involves compounds that contain no hydroxyl group at the 3-position To-date, much of the DA reactions of 2-pyrones (no hydroxyl group...

Ngày tải lên: 14/09/2015, 08:47

... base-catalyzed DA reactions Thus it should come as no surprise that 4a can also be used as a diene in Diels-Alder reactions The study of DA reactions of 4a shall occupy a major part of this chapter ... Michael reaction of 4b with β-nitro styrenes In view of the synthetic application of the DA product of N-arylsulfonyl-3hydroxy-2-pyridone with acrylates, an attempt to react 4b with alkyl acrylates ... the addition of the sulfonyl group can be performed selectively on nitrogen Deprotection of the TBS group using the standard protocol of BF3.Et2O in CH2Cl2 gave a 60% overall yield of the N-arylsulfonyl-3-hydroxy-2-pyridone...

Ngày tải lên: 14/09/2015, 08:47

... methods All reactions were performed in oven-dried round bottom flasks or glass vials The flasks were fitted with rubber septa and reactions were conducted under a positive pressure of nitrogen, ... synthesis of N-arylsulfonyl-3-hydroxy-2-pyridone Pyridones 4b, 4c and 4d were prepared according to the published procedure.2 4.2.6 Procedure for the synthesis of 9a3 To a solution of 4b (219.9 ... C17H22NO4S 336.1264 4.2.10 Procedure for the synthesis of 9e6 The procedure for the protection of the alcohol is the same as for the synthesis of 4b White solid, 85% yield H NMR (500 MHz CDCl3 ppm):...

Ngày tải lên: 14/09/2015, 08:47