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Agnieszka J. Rybarczyk‐Pirek Magdalena Maecka Sawomir J. Grabowski Jolanta Nawrot‐Modranka 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):o405-o406
In (E)‐3‐{[(diphenoxyphosphoryl)methylhydrazono]methyl}‐4H‐1‐benzopyran‐4‐one, C23H19N2O5P, the benzopyran–methylhydrazone moiety is planar and the two phenoxy phenyl rings are inclined at angles of 21.29 (6) and 89.33 (5)°. Weak C—H?O and C—H?N intramolecular interactions exert some influence on the planarity and orientation of that moiety. 相似文献
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Pernak J Syguda A Mirska I Pernak A Nawrot J Pradzyńska A Griffin ST Rogers RD 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(24):6817-6827
A total of sixty-three choline derivative-based ionic liquids in the forms of chlorides, acesulfamates, and bis(trifluoromethylsulfonyl)imides have been prepared and their physical properties (density, viscosity, solubility, and thermal stability) have been determined. Thirteen of these salts are known chlorides: precursors to the 26 water-soluble acesulfamates, 12 acesulfamates only partially miscible with water, and 12 water-insoluble imides. The crystal structures for two of the chloride salts-(2-hydroxyethyl)dimethylundecyloxymethylammonium chloride and cyclododecyloxymethyl(2-hydroxyethyl)dimethylammonium chloride-were determined. The antimicrobial (cocci, rods, and fungi) activities of the new hydrophilic acesulfamate-based ILs were measured and 12 were found to be active. The alkoxymethyl(2-hydroxyethyl)dimethylammonium acesulfamates have been shown to be insect feeding deterrents and thus open up a new generation of synthetic deterrents based on ionic liquids. The alkoxymethyl(2-decanoyloxyethyl)dimethylammonium bis(trifluoromethylsulfonyl)imides have also been shown to act as fixatives for soft tissues and can furthermore be used as substitutes for formalin and also preservatives for blood. 相似文献
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Bożena Łozowicka Piotr Kaczyński Jan Nawrot 《Central European Journal of Chemistry》2013,11(12):2120-2133
Five positional isomers and thirty derivatives of alpha-asarone wereobtained as a bioactive set of substances, and their deterrent activity against the Colorado potato beetle was studied. The lipophilicity values of thirty-six compounds were determined by using experimental, chromatographic and theoretical methods. The logk w values for all compounds were determined by reversed-phase high-performance liquid chromatography using five different columns. The octan-1-ol/water partition coefficients values were determined experimentally as a measure of lipophilicity. For the purpose of comparison, theoretical lipophilic parameters for all compounds were calculated with the use of chemical programs. The experimental, chromatographic and calculated values were compared using linear regression analysis. The most significant correlations were found between the chromatographic lipophilicities using methanol/water for all tested columns and calculated values. It has been found that 13 compounds have the lowest lipophilicities, which correspond to deterrent activity. The presented results show that the computational method is useful for determining the lipophilicity of a series of homologues, but not for positional isomers. In addition, this study shows that determination of lipophilicity using HPLC with various stationary phases is practical and reasonable for all alpha-asarone derivatives. 相似文献
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Cybulski J Wiśniewska A Kulig-Adamiak A Lewicka L Cieniecka-Rosłonkiewicz A Kita K Fojutowski A Nawrot J Materna K Pernak J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(30):9305-9311
A new group of quaternary ammonium lactate based ionic liquids have been prepared and characterized. Didecyldimethylammonium (DDA) and benzalkonium (BA) D,L- and L-lactates are air-stable, hydrophilic, surface-active salts. They are very effective antibacterial and antifungal agents, especially the DDA lactates, against Streptococcus mutants and Candida albicans. Their activities are comparable or more effective than the original benzalkonium chloride. In addition, they have been shown to be good insect-feeding deterrents. However, they are poor antifungal agents for wood preservation. The toxicity of the DDA and BA lactates has also been studied and the results are presented in this paper. 相似文献
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[structure: see text] Three different approaches were used for the synthesis of dinucleoside methanephosphonamidates [3'-NH-P(O)(CH3)O-5'], starting from dichloromethylphosphine or dichloromethanephosphonate as the phosphorus-containing moiety. 5'-DMT-3'-amino-3'-deoxythymidine and N(4)-benzoyl-5'-DMT-3'-amino-2',3'-dideoxycytidine were used as the aminonucleoside precursors and the respective 3'-protected nucleosides (thymidine or N(4)-benzoyl-2'-deoxycytidine) as the 5'-hydroxyl reagents. 相似文献
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[reaction: see text] Allyl, isopentenyl, geranyl, citronellyl, farnesyl, and phytyl alcohols were transformed in good yield (>60%) into their phosphorothioates via a DBU-assisted 1,3,2-oxathiaphospholane ring-opening condensation with 2-(2-cyanoethoxy)-2-thiono-1,3,2-oxathiaphospholane, a reagent that is stable and easy to handle, followed by subsequent removal of the 2-cyanoethyl group from the intermediate phosphorothioate diester under basic conditions. 相似文献
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Basicity differences among peptide bonds 总被引:1,自引:0,他引:1
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Barbara Nawrot Krzysztof W. Pankiewicz Robert A. Zepf Kyoichi A. Watanabe 《Journal of carbohydrate chemistry》2013,32(1):95-114
Abstract Benzyl 2,5-di-O-(tert-bstvldimethvl)silvl-3-O-triflvl-β-D-ribofsranoside (13) underwent triflyl migration upon O-desilylation with triethylammonium hydrogen fluoride in tetrahydrofuran affording benzyl 2-O-triflyl-β-D-ribo-furanoside (7) in ca. 5% yield, together with three other products, benzyl 3-O-triflyl-β-D-ribofuranoside (17), benzyl 2-O-(tert-butyldimethyl)silvl-3-O-triflyl-β-D-ribo-furanoside (18) and benzyl 3-deoxy-β-D-glvceropento-furanos-2-uloside (16). In order to confirm the triflyl migration, a series of reactions were performed. 相似文献