摘要:

A known colorimetric method for the determination of sulfonamides in biological media has been modified and checked by means of radio‐assay using a35S labelled sulfonamide. Attention is drawn to the loss of sulfonamides during precipitation of proteins. It is shown that an accurate evaluation of results is only possible by using a calibration curve plotted on the basis of relevant recovery experiment

ISSN:0018-019X    

DOI:10.1002/hlca.19610440112

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

d,l‐1, 2‐Dianilino‐1,2‐diphenyl‐ethane reacts readily and specifically with aldehydes to form substitutedd,l‐1,3,4,5‐tetraphenylimidazolidines, which are highly crystalline compounds with sharp melting points distributed over a wide range of temperature. The reaction has been used for the characterization of the commoner aliphatic aldehydes and several derivatives of benzaldehyde. The neutralisation equivalents of these imidazolidines can be determined bv titration in acetic anhydride with 0,1Nperchloric acid i

ISSN:0018-019X    

DOI:10.1002/hlca.19610440113

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

AbstractDie Dampfdrucke von gewöhnlichem Sauerstoff und einem schweren Sauerstoff mit 0,21%l6O, 0,15%l7O und 99,64% IS0 wurden zwischen 63°K und dem Siedepunkt miteinander verglichen. Umgerechnet auf reine Isotope wird das Dampfdruckverhältnis durch die Beziehungdargestellt. Der Siedepunkt des18O2, liegt 0,105° höher als der des16O2(90,19,° K); der Dampfdruckunterschied der beiden Isotope betragt bei dieser Temperatur 8,26 mm Hg. Der Unterschied der Verdampfungswärmen macht 6,28 cal/Mol aus, wobei dem schweren Sauerstoff die höhere Verdampfungswärme zukommt. Aus der Temperaturabhängigkeit der Differenz der Verdampfungswärme folgt, dass die Molwärme des flüssigen18O2bei 90°K um 0,06, cal/Mol°, bei 65°K um 0,12 cal/Mol° grosser al

ISSN:0018-019X    

DOI:10.1002/hlca.19610440114

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

Some new carbamates and N‐substituted barbituric acids with carbamated side chain have been prepared. Several of these substances show interesting pharmacological propertie

ISSN:0018-019X    

DOI:10.1002/hlca.19610440115

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

N‐CBO‐L‐prolyl‐L‐isoleucyl‐glycine ethyl ester and N‐CBO‐L‐prolyl‐L‐valylglycine ethyl ester are synthesized by recurrent methods. Amidification of the ester group, splitting of the CBO group and condensation with N‐CBO‐L‐glutaminyl‐ L‐asparaginyl‐S‐benzyl‐L‐cysteinyl‐azide affords the two respective hexapeptides, which after splitting of the CBO group are condensed with N‐tosyl‐S‐benzyl‐L‐cysteinyl‐ L‐tyrosyl‐L‐isoleucyl‐azide. Cleavage of the protecting groups of the resulting two nonapeptides with sodium in liquid ammonia, oxydation with air in dilute aqueous solution and purification by counter‐current distribution, affords the desired cyclic nonapeptide amides : Ileu8‐oxytocin and Val8‐oxytocin. When tested on the cat

ISSN:0018-019X    

DOI:10.1002/hlca.19610440116

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

N‐CBO‐L‐arginyl‐L‐arginine is condensed withL‐prolyl‐L‐valine methyl ester and, after splitting of the CBO group,L‐arginyl‐L‐arginyl‐L‐prolyl‐L‐valine methyl ester is obtained. This is condensed with N‐trityl‐glycyl‐Nϵ‐CBO‐L‐lysyl‐Nϵ‐CBO‐L‐lysine and, after selective splitting of the trityl group, glycyl‐Nϵ‐CBO‐L‐lysyl‐Nϵ‐CBOL‐ lysyl‐L‐arginyl‐L‐arginyl‐L‐prolyl‐L‐valine methyl ester is obtained. Condensation of this heptapeptide with N‐trityl‐glycyl‐Nϵ‐CBO‐L‐lysyl‐L‐prolyl‐L‐valine yields an endecapeptide, which, after selective splitting of the trityl group, is converted into the trihydrochloride of glycyl‐Nϵ‐CBO‐L‐lysyl‐L‐prolyl‐L‐valyl‐glycyl‐Nϵ‐CBO‐L‐ lysyl‐Nϵ‐CBO‐L‐lysyl‐L‐arginyl‐L‐arginyl‐L‐prolyl‐L‐valine methyl ester. The identity, the chemical purity and the optical homog

ISSN:0018-019X    

DOI:10.1002/hlca.19610440117

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

The cyclic decapeptide 8α, another of the four possible structures deduced for the natural polymyxin B1by the usual degradation methods, has been synthesized. It appears not to be identical with polymyxin B1in view of its reduced antibacterial activityin vitro

ISSN:0018-019X    

DOI:10.1002/hlca.19610440118

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

AbstractAusgehend von D‐Glucosamin‐hydrochlorid, bzw. D‐ undL‐Glucosaminsäure wurden fünf sterisch eindeutig festgelegte, strukturell dem Muscarin nahestehende, bisquaternäre Ammonsalze synthetisiert. Die Herstellung von Chitarsäure aus Glucosaminsäure, von Tetrahydrofuran‐2,5‐dicarbonsäure aus Furan‐2,5‐dicarbonsäure und von 2,5‐Anhydro‐D‐mannozuckersäure aus D‐Glucosamin

ISSN:0018-019X    

DOI:10.1002/hlca.19610440119

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

AbstractEn vue d'une étude concernant la solubilité dans le systéme quaternaire\documentclass{article}\pagestyle{empty}\begin{document}$${\rm Na}^ + - {\rm K}^ + - {\rm C}_{10} {\rm H}_7 {\rm SO}_3 \left( 1 \right)^ - - {\rm C}_{10} {\rm H}_7 {\rm SO}_3 \left( 2 \right)^ - - {\rm H}_2 {\rm O},$$\end{document}nous avons mis au point une méthode permettant de doser l'anion C10H7S03(2)− («anion B−») en présence de l'anion C10H7S03(2)− («anion A−») avec une précision de 1 à 2%, calculée sur la somme

ISSN:0018-019X    

DOI:10.1002/hlca.19610440120

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY

摘要:

For the synthesis of β1–19corticotropin‐Glu5‐γ‐amide1) a derivative of lysine was needed involving a blocking group on Nϵeasily removable by mild acid treatment. Nϵ‐t‐Butoxycarbonyl‐L‐lysine was synthesized and found to be a very versatile compound. The Nϵ‐t‐butoxycarbonyl group is readily removed by trifluoroacetic acid and by aqueous HCI, it is not cleaved by anhydrous or aqueous acetic acid in the experimental conditions described here. This allows its use in conjunction with the N‐trityl group which is easily hydrolysed by aqueous acetic acid. Needless to point out, it may also be used along with the carbobenzoxy or p‐phenylazocarbobenzoxy groups which may preferentially be removed by catalytic hydrogenation. A number of derivatives and peptides of Nϵ‐t‐butoxycarbonyl‐L‐lysine are described, among these are trityl·Lys(BOC)‐Lys(BOC)·OH7) and PZ·Lys(BOC)‐Pro‐Val‐Gly·OH, both intermediates in the synthesis of the nonadecapeptide with high corticotropic activity1). The derivatives described here should also be u

ISSN:0018-019X    

DOI:10.1002/hlca.19610440121

出版商:WILEY‐VCH Verlag GmbH    

年代:1961

数据来源: WILEY