Search

Your search keyword '"Kiehlmann, Eberhard"' showing total 34 results
Start Over "Kiehlmann, Eberhard"
34 results on '"Kiehlmann, Eberhard"'

3. Journal Coverage by the Major Chemical Title and Abstract Publications

Author

Kiehlmann, Eberhard

Abstract

The journal coverage provided by Chemical Titles,'' Current Contents,'' Science Citation Index,'' Chemischer Informationsdienst,'' and Index Chemicus'' is discussed and compared with the CASSI list of the thousand primary journals most frequently cited by Chemical Abstracts.'' (10 references) (Author/NH)

Published
1972

4. Organization and Efficient Manual Searching of the Major Chemical Title and Abstract Publications

Author

Kiehlmann, Eberhard

Abstract

Science Citation Index'' and several new Chemical Abstracts''' indexes are discussed as effective tools for retrospective literature work and a comparison is made of the features of Chemischer Informationsdienst,'' Index Chemicus,'' Chemical Titles,'' and Current Contents'' as the main sources of current chemical information. (9 references) (Author/SM)

Published
1973

11. Epimerization, transacylation and bromination of dihydroquercetin acetates; synthesis of 8-bromodihydroquercetin.

Author

Kiehlmann, Eberhard and Szczepina, Monica G.

Abstract

Dihydroquercetin ( dhq) and its 3-acetate react with acetic anhydride in the absence of a base catalyst to yield mixtures of partially acetylated products. Three new esters were characterized by NMR spectroscopy as dhq 3,7,3′-triacetate, 3,7,4′-triacetate and 5,7,3′,4′-tetraacetate. At its melting point neat dhq 3,7,3′,4′-tetraacetate is partially converted to dhq 3,3′,4′-triacetate and dhq pentaacetate by intermolecular acetyl transfer. Dhq 7,3′,4′-triacetate yields exclusively dhq 3′,4′-di- and 3,7,3′,4′-tetraacetate under these conditions. The acetylation/deacetylation reactions are accompanied by partial epimerization: 3 new acetates with 2,3- cis stereochemistry ( dhq 3-, 3,7,3′,4′-tetra- and penta -) were identified. Dhq and its 3,7,3′,4′-tetraacetate undergo regiospecific dibromination at C-6 and C-8 with excess N-bromosuccinimide in polar solvents, and 6,8-dibromo- dhq can be regioselectively debrominated to 8-bromo- dhq with sodium sulfite. [ABSTRACT FROM AUTHOR]

Published
2011
Full Text
View/download PDF

21. Alkaline methanolysis of 1,1,1-trichloro-2-hydroxy-4-alkanones

Author

Kiehlmann, Eberhard, Wells, J. I., and Reeve, Wilkins

Abstract

Derivatives of the carboxylic acids RCOCH2CH(OCH3)COOH and RCOCH=CHCOOH (R = Me, i-Bu, or tert-Bu) have been identified among the major methanolysis products of three 1,1,1-trichloro-2-hydroxy-4-alkanones, RCOCH2CH(OH)CCl3. In addition, β-methoxy esters RCOCH(OCH3)CH2COOCH3are obtained if hydrogen atoms are present at the alkyl carbon directly attached to the carbonyl group (R = Me or i-Bu). 1,1,1-Trichloro-2-hydroxy-4-pentanone (1) yields the known methyl 5-chloro-2,4-pentadienoate (9) as a minor by-product. An α,α-dichloro epoxide (15) is postulated as the key intermediate in the methanolysis mechanism leading to the β-methoxy esters.

Published
1976
Full Text
View/download PDF

32. Biography and Genealogy Master Index:Cumulation of Supplements: 2011-2015

Author

Gale Research Inc and Gale Research Inc

Abstract

The Biography and Genealogy Master Index is designed to help you easily determine which publication to consult for biographical information. Indexed sources cover both living and deceased persons from every field of activity and from every country in the world. Typically current, readily available, standard reference works are indexed. Look for supplement volume updates to this valuable biographical research tool twice a year. These volumes are cumulated every five years. More than 15 million citations compiled from more than 5,000 editions and volumes of approximately 1,700 current and retrospective biographical sources are included in the Biography and Genealogy Master Index base set and its supplements. In total, Biography and Genealogy Master Index provides coverage of nearly 5 million contemporary and historical figures from authors to scientists, from boxers to fashion designers, from Adam and Eve to Frank Zappa.

Published
2017

33. American Men & Women of Science : A Biographical Directory of Today's Leaders in Physical, Biological, and Related Sciences

Author

Kalte, Pamela M., Nemeh, Katherine H., Schusterbauer, Noah, Kalte, Pamela M., Nemeh, Katherine H., and Schusterbauer, Noah

Subjects
Scientists--United States--Biography, Scientists--Canada--Biography, Scientists--United States--Directories, Scientists--Canada--Directories, Science
Abstract

This edition profiles living persons in the physical and biological fields, as well as public health scientists, engineers, mathematicians, statisticians, and computer scientists.

Published
2005

Catalog

Books, media, physical & digital resources
See catalog results