Results 201 to 210 of about 14,361 (259)

On binary operators and their derived relations

BIT, 1988
Considering a list of abstract binary operations and relations, the author gives a sequence of seven simple to prove, but interesting and very useful theorems, which appear frequently in algebra and other fields. All results are known, but the approach is nice and appropriate for teaching, with a good generality.
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Programmed derivations of relational structures

2005
Derivations of relational structures by applying productions are considered. The corresponding concepts are taken from the existing algebraic (category theory) approach to transformations of relational structures. An idea of programs for defining sets of derivations is introduced. A number of programming constructs is introduced to specify applications
Andrea Maggiolo-Schettini, Józef Winkowski   +1 more
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Flavone and xanthone derivatives related to fluoroquinolones

Il Farmaco, 1999
A number of flavone and xanthone derivatives bearing some characteristic features of fluoroquinolones such as the fluorine atom and an ortho piperazine ring are described. The new compounds have been tested for possible cytotoxic and antimicrobial activities.
S. MARI, ROSSI, Maddalena, P. VALENTI, P. DA RE   +3 more
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Selenotyrosine and related phenylalanine derivatives

Bioorganic & Medicinal Chemistry, 2001
A new series of Se-substituted phenylalanine derivatives has been synthesized having the para position of the phenyl ring substituted by selenocyanate (-SeCN), seleninic acid (-SeO(2)H), or selenol (-SeH) functional groups. The starting material for synthesis was 4'-aminophenylalanine, which is readily available in DL- or L- forms.
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Derivations of Onsager’s Reciprocal Relations

The Journal of Chemical Physics, 1954
Two derivations of Onsager's reciprocal relations are presented in simplified form, and the range of their validity is discussed.
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Silipramine and related derivatives

Journal of Organometallic Chemistry, 1978
A series of new 10,11-dihydro-5H-dibenzo[b,f]silepins are prepared from the reaction o,o′-dilithiobibenzyl with the chlorosilanes HSiCl3, ClCH2CH2CH2SiCl3, MeSiHCl2 and MeSi(CH2CH2CH2Br)Cl2. The only isolated silepin product produced from HSiCl3 is the spiro derivative.
Joyce Y. Corey, Roberta L. Farrell
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The Derivation of Syntactic Relations

1998
Abstract Alongside explicit specifications of “syntactic feature” and “permissible syntactic feature bundle” (i.e., a possible syntactic category), perhaps the most fundamental construct postulated within syntactic theory is that of a “syntactic relation.” For example, the following are each considered to be core syntactic relations. a. (
Samuel David Epstein Erich M Groat Ruriko Kawashima, Hisatsugu Kitahara   +1 more
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Carboxyboranes and Related Derivatives

ChemInform, 2006
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
D. Gabel, M. B. El‐Zaria
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PhanePhos and Related Derivatives

2012
(R)-4,12-Bis(diphenylphosphino)-[2.2]-paracyclophane [364732-88-7] C40H34P2 (MW 576.65) InChI = 1S/C40H34P2/c1-5-13-35(14-6-1)41(36-15-7-2-8-16-36)39-29-31-21-25-33(39)27-23-32-22-26-34(28-24-31)40(30-32)42(37-17-9-3-10-18-37)38-19-11-4-12-20-38/h1-22,25-26,29-30H,23-24,27-28H2 InChIKey = GYZZZILPVUYAFJ-UHFFFAOYSA-N Physical Data ...
Luis A. Adrio, King Kuok Hii
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Oxazolopyrimidine and thiazolopyrimidine derivatives related to the xanthines

Journal of the American Pharmaceutical Association (Scientific ed.), 1955
Abstract 2,6(1H,3H)‐Oxazolo[5.4‐d]pyrimidinedione and 2,6(1H,3H)‐thiazolo[5.4‐d]‐pyrimidinedione are xanthine analogs related to oxazolo [5.4‐d]pyrimidine and thiazolo [5.4‐d] pyrimidine in the same way that xanthine, 2,6(1H, 3H)‐7‐imidazo‐[4.5‐d]pyrimidinedione, is related to purine, 7‐imidazo[4.5‐d]pyrimidine.
G P, HAGER, C, KAISER
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