摘要:

AbstractNew synthetic methods developed in the field of organotin compounds since 1959 are reviewed. The use of alkyl aluminum compounds brings an advance in the preparation of tetraalkyltin derivatives, alkyltin halides, and alkyltin hydrides. Organotin hydrides offer new possibilities for the production of monomeric and polymeric organotin compounds. Diethyltin and diphenyltin, which are obtained by catalytic dehydrogenation of the respective dialkyltin dihydrides, are cyclic compounds. – The literature since 1959 is reviewe

ISSN:0570-0833    

DOI:10.1002/anie.196301651

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractInsect hormones attracted the interest of endocrinologists only comparatively recently. This is partly due to the fact that an equivalent of sex hormones – the classical hormones of vertebrate physiology – is unknown in insects. Castration has no marked effect on the secondary sexual characters. Insect hormones act primarily on developmental processes; the metamorphosis hormone, ecdysone, is the best studied. Recent investigations have shown that ecdysone has the empirical formula C27H44O6and belongs to the streroids. The mechanism of its action is seen in its influence on the chromosomes. – Other hormone‐like substances, the pheromones, are outstanding for their high activity; a few molecules are sufficient to trigger the characteristic behavioural r

ISSN:0570-0833    

DOI:10.1002/anie.196301751

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractIt is shown that the methyl esters of many diastereoisomeric N‐trifluoroacetyldipeptides can be separated by gas chromatography on Golay columns. This makes it possible for the first time to carry out accurate quantitative investigations of recemization occurring during peptide synthesis without resort to measurements of optical rotation or enzymatic cleavage, and witout having to isolate the peptides. Some well‐known methods of forming peptides were examined using the synthesis of the methyl ester of carbobenzoxy‐L‐valyl‐L‐valine as an example. The synthesis of the methyl ester of N‐trifluoroacetyl‐L‐valyl‐L‐valine was investigated as a model for the linking of peptides. The influence on racemization of numerous factors was determined. General conclusions could be drawn regard

ISSN:0570-0833    

DOI:10.1002/anie.196301831

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractShock waves provide a simple means of achieving high temperatures and hence of studying the kinetics of endothermal processes, e.g. dissociation reactions, above 100 °K. Detonations can also be used for this purpose, but are restricted to a few exothermal mixtures. The production and properties of shock waves and detonations and the most important analytical methods used for kinetic investigations are described, and some typical results are discussed

ISSN:0570-0833    

DOI:10.1002/anie.196301891

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302101

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302112

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302122

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302132

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302142

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196302152

出版商:Hüthig&Wepf Verlag    

年代:1963

数据来源: WILEY