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Alkyl Derivatives (alkyl + derivative)
Selected AbstractsChemInform Abstract: Synthesis of Insecticidally Active Halofenozide-[(acyloxy)alkoxy]carbonyl and (Acyloxy)alkyl Derivatives.CHEMINFORM, Issue 16 2002Mark J. Mulvihill Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis and Evaluation of S - and C(1) -Substituted Analogues of LincomycinHELVETICA CHIMICA ACTA, Issue 2 2009Marie-Pierre Collin Abstract New thioglycosides and C(1) -alkylated thioglycosides (S -ulosides) of lincomycin were synthesized, and their antibiotic activities were determined. The S -aryl and S -arylalkyl analogues 11a,11i were obtained by S -glycosylation of the sulfoxides 7 with arenethiols, or by S -alkylation of the thiol 14 with alkyl bromides. Lincomycin derivatives 27, 32a, 32b, 38a, 38b, 44, and 47 were prepared via Henry reaction or Michael addition of the lincosamine-derived 1-deoxy-1-nitropyranoses 22. The S -alkyl derivatives showed a similar activity and specificity as lincomycin. Lipophilic S -uloside analogues were two- to fourfold less active than the parent antibiotic, whilst the hydrophilic analogues were inactive. [source] Alumino-organic derivatives of some dioximesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 10 2002Nicolae Voiculescu Abstract The alumino-organic combinations of the dioximes (DOxH2) examined in this paper result from the substitution of the hydrogen bonds of oximes by alumino-organic groups. Relative to the same alumino-organic derivatives, diphenylglyoxime (DPGH2) behaves similarly to dimethylglyoxime (DMGH2). The chemical reactivity of DPGH2 towards these alumino-organic compounds is, however, less than in the case of DMGH2. An exception is the monomer state of (DPG)[Al(i-C4H9)2]2 in benzene solution. The behavior relative to amines of alkyl derivatives is similar to that found in coordinated oximes. In contrast, phenylaluminum derivatives of DMGH2 and DPGH2 are not soluble in amines. All compounds reported in this paper were separated from the reaction mixture as colored powders and were characterized by chemical analyses, IR spectroscopy, X-ray diffraction spectra and 1H NMR. Finally, a comparison between the reactivity of free and coordinated dioximes is briefly considered. It is hoped that such comparisons will throw light on the problems associated with the reactivity of free and coordinated oxides versus alumino-organic compounds. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enantioselective chromatography of alkyl derivatives of 5-ethyl-5-phenyl-2-thiobarbituric acid studied by semiempirical AM1 methodCHIRALITY, Issue 8 2002Krzysztof Zborowski Abstract Complexation of alkyl derivatives of 5-ethyl-5-phenyl-2-thiobarbituric acid (2-thiophenobarbital) enantiomers by ,-cyclodextrin was investigated by the AM1 method. The inclusion complexes of ,-cyclodextrin with neutral and anionic forms of these enantiomers have been modeled and energetically optimized. The chiral discrimination of enantiomers was analyzed in terms of differences in the interaction energies. The calculated interaction energies between each enantiomer of the investigated 2-thiobarbiturates and ,-cyclodextrin confirm the ability of ,-cyclodextrin to act as a mobile phase additive in reversed-phase HPLC to separate enantiomers by liquid chromatography and rationalize their order of elution. Chirality 14:632,637, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||