摘要:

AbstractIn six solvents theL‐Ddiastereoisomers of H‐gly‐asp‐ser‐gly‐OEt, H‐gly‐glu‐ser‐gly‐OEt, H‐gly‐asp‐ser(Ac)‐gly‐NH2and H‐gly‐glu‐ser(Ac)‐gly‐NH2have higher Rtvalues

ISSN:0165-0513    

DOI:10.1002/recl.19640830302

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractThe heterogeneous sulphonation of toluene with 81.9 and 95.9 wt‐% aqueous sulphuric acid has been studied at 25°. The isomer distribution which deviates from that observed in homogeneous sulphonation, varies with toluene conversion and with toluene to sulphuric acid volume ratio. The content ofp‐toluenesulphonic acid is higher under heterogeneous conditions than under homogeneous conditions. It is suggested that the variation in isomer distribution is due chiefly to the presence of increasing amounts of sulphonic acids in the sulphuric acid phase.The heterogeneous sulphonation of toluene proceeds mainly in the sulphuric acid phase. Some sulphonation in the toluene phase by sulphur trioxide may take place as well. However, the latter process is of little ‐ if any ‐ im

ISSN:0165-0513    

DOI:10.1002/recl.19640830303

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractLa synthèse des tétraalcoylméthanes en C17a été effectuée suivant une méthode basée sur une synthèse deKnoevenaegel.Les courbes viscositè‐température des hydrocarbures obtenus ont été tracées entre 20 et 120° et l'allure des courbes confrontée avec les formules proposées par:AndradeetSheppard, Walther, HugeletWatermann.Entre deux températures dont la différence est inférieure α 40°, l'écart relatif entre les valeurs mesurées et les valeurs calculées par interpolation α l'aide des trois dernières formu

ISSN:0165-0513    

DOI:10.1002/recl.19640830304

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractBei der Einwirkung von Peressigsäure auf 2‐Dimethylaminopyridin entsteht ein N‐Oxyd welches von dem N1‐Oxyd, das aus dem N‐Oxyd des 2‐Chloropyridin durch Aminolyse erhalten worden ist, verschieden ist; das Sauerstoffatom in der neuen Verbindung befindet sich offenbar am Stickstoff der Dimethylaminogruppe (N2‐Oxyd). Bei der Nitrierung des bekannten N1‐Oxydes entsteht ein N1‐Oxyd des 2‐Dimethylamino‐5‐nitropyridins. Mehrere Derivate der letzten Verbindung, darunter das Reduktionsprodukt: das N1‐Oxyd des 5‐Amino‐2‐dimethylamino‐

ISSN:0165-0513    

DOI:10.1002/recl.19640830305

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractA synthesis is described of the N‐terminal octapeptide sequence derived from the pancreatic hormone glucagon (glucagon 1

ISSN:0165-0513    

DOI:10.1002/recl.19640830306

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

Abstractn‐Propyl bromide is readily isomerized to isopropyl bromide in carbon disulphide solution under the influence of aluminium bromide at ‐20°. The reaction may be followed by infrared spectroscopy or by gas‐liquid chromatography. Rate data can be accommodated only by using two kinetic equations, obtaining at high and low molar intake ratios of the reactants, respectively.No incorporation of deuterium takes place when carrying out the reaction in the presence of deuterium bromide, indicating that the isomerization does not involve reversible dehydrobromination.Runs with 2‐deuteratedn‐propyl bromide show a significant isotope effect, a hydrogen atom shifting about 3.4 times more rapidly than a deuterium atom.These and other results obtained may be interpreted in terms of reversible (partial) ionization, followed by a 1,2‐hy

ISSN:0165-0513    

DOI:10.1002/recl.19640830307

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractA method is described for the preparation of bis‐β‐glycerophosphatidic acids starting from αγ‐diglycerides with one or two saturated compone

ISSN:0165-0513    

DOI:10.1002/recl.19640830308

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractWe describe the preparation of tris(2‐stearoyloxyethyl) phosphate, starting from monostearoylglycol (2‐stearoyloxyethanol) and phosphorus oxychloride and from silver bis(2‐stearoyloxyethyl) phosphate and stearoylglycol iodohydrin. The alkaline hydrolysis of the first‐mentioned compound is inves

ISSN:0165-0513    

DOI:10.1002/recl.19640830309

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractA number of triorganotin salts of acetylenemono‐ and di‐carboxylic acids upon being heated lose carbon dioxide to give organotin‐substituted acetylenes.Some others decompose in an irregular way and in one case simultaneous decarboxylation and disproportionation occurs.Tributyltin azide adds to diethyl acetylenedicarboxylate with the formation of 1‐tributylstannyl‐4,5‐di‐ethoxycarbonyl

ISSN:0165-0513    

DOI:10.1002/recl.19640830310

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY

摘要:

AbstractAcetylenic benzyl ethers, IV, with R  CH3or C2H5and R′  H or CH3have been prepared according to the scheme below. These compounds rearrange very easily into 1,3‐dialkyl‐2‐indanones, V, on refluxing in tetrachloromethane and into 1‐hydroxy‐1‐phenyl‐2‐alkynes with sodam

ISSN:0165-0513    

DOI:10.1002/recl.19640830311

出版商:WILEY‐VCH Verlag    

年代:1964

数据来源: WILEY