摘要:

AbstractPhenols produce colours with chlorine/o‐tolidine, a method usually applied for the detection of NH‐groups. A series of phenols has been tested and the results are compared with standard tests for phenols. The procedure described is particularly suitable for spray reagents in paper and thin layer chromatogra

ISSN:0018-019X    

DOI:10.1002/hlca.19650480102

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractZur Aufklärung der absoluten Konfiguration von Terpinenol‐(4) wurde (−)‐Terpinenol‐(4) über das (+)‐Carvomenthol mit dem (−)‐Limonen verbunden. Das (−)‐Terpinenol‐(4) besitzt daher die (4R)‐Konfiguration. Für das (+)‐Terpinenol‐(4) wurde auf indirektem Wege die

ISSN:0018-019X    

DOI:10.1002/hlca.19650480103

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThe stability constants of the methylmercury complexes CH3HgL1−λwith a considerable number of ligands Lλ−have been determined (Table 1). Like H+, the cation CH3Hg+reveals the coordination number 1 almost exclusively. Some ligands form also binuclear adducts (CH3Hg)2L2−λand sulfide even forms (CH3Hg)3S+. The coordination behaviours of CH3Hg+and H+however are very different concerning the selection of ligands, the former being a soft and the latter a hard acid in the sense of PEARSON. The entropy ΔS of the reaction: H++ L−→ HL is more positive by about 14 c.u. than ΔSof the reaction: CH3HG++ L−→ CH3HgL. The hydrogen ion in aqueous solution has a far greater order producing action on the solvent than CH3Hg+. Two dyes also have investigated, which may serve as indicators for CH3HG+and for the determination of pCH3H

ISSN:0018-019X    

DOI:10.1002/hlca.19650480104

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThe structures of complexes with ligands containing the PO32−group – monomethyl phosphate, diphosphate, monomethyl diphosphate and adenosine‐5′‐triphosphate – have been studied by infrared absorption measurements in aqu

ISSN:0018-019X    

DOI:10.1002/hlca.19650480105

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThe temperature dependence of the EMF of glass reference electrode assemblies for pH measurements is discussed. A simple arrangement having an EMF of zero mV at pH = 7,0, independent of the temperature, suitable for high temperature applications, is described.

ISSN:0018-019X    

DOI:10.1002/hlca.19650480106

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThe seeds ofVallaris solanacea(ROTH) O.K. are very rich in cardiac glycosides. Eight KEDDE‐positive substances have been detected through paper‐ and thinlayerchromatography. All of them could be isolated in crystalline form. The yields varied between 0,03% and 0,9% with respect to the dry weight of the se

ISSN:0018-019X    

DOI:10.1002/hlca.19650480107

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThe seven new substances, isolated from the seeds ofVallaris solanacea(ROTH) O. K., have been shown to have the following structures:Vallaroside (substance D) = digitoxigenin‐α‐L‐vallaropyranoside, solanoside (substance F) = digitoxigenin‐α‐L‐acofriopyranoside, vallarosolanoside (substance E) = oleandrigenin‐α‐L‐vallaropyranoside, 16‐deacetyl‐16‐anhydro‐acoschimperoside P (substance H) = 16‐anhydro‐g

ISSN:0018-019X    

DOI:10.1002/hlca.19650480108

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

Abstract1. Es wird gezeigt, dass substituierte Allylbromide Phenol mehr an Kohlenstoff alkylieren als Allylbromid selbst.

ISSN:0018-019X    

DOI:10.1002/hlca.19650480109

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractESR spectra of the radical anions obtained from 1,4,5,8‐tetraazanaphthalene by electrolytic and chemical reduction have been recorded. The hyperfine structure of the electrolytically generated anion (solvent: N,N‐dimethylformamide; counter‐ion: tetraethylammonium) is that of an unassociated species, whereas evidence of strong ion‐pairing can be derived from the spectra of the chemically prepared anions (solvent: 1,2‐dimethoxyethane; counter‐ion

ISSN:0018-019X    

DOI:10.1002/hlca.19650480110

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY

摘要:

AbstractThin‐layer chromatography is applied to the separation of234Th from natural238U and to the separation of the neutron activation products of NH4Cl:38Cl,35S and32

ISSN:0018-019X    

DOI:10.1002/hlca.19650480111

出版商:WILEY‐VCH Verlag GmbH    

年代:1965

数据来源: WILEY