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1.
J. J. Langer E. Uler K. Golankiewicz 《Applied Physics A: Materials Science & Processing》1987,43(2):139-141
A polarized N-O bond behaves as an intramolecular p-n junction. Their rectifying properties have been found in 1,3-dimethylisoxasole, 1-phenylsydnone, and 1-(4-methylphenyl)sydnone molecules based on H1-NMR data. 相似文献
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Adam S. Plaziak Jaroslaw Spychala Hanna Wjtowicz Jerzy J. Langer Halina Thiel-Pawlicka Krzysztof Golankiewicz 《Journal of mass spectrometry : JMS》1992,27(11):1293-1298
Ortho-. meta- and para-isomers of N-(pyrimidin-4-yl)aminobenzoic acid and their methyl esters were investigated by electron impact mass Spectrometry. Their fragmentation was found to be strongly dependent on the position of the substituent in the aminobenzoic moiety. Two different kinds of ortho effect were studied and confirmed with the aid of deuterium-labelled derivatives. 相似文献
3.
W. Zielenkiewicz B. Golankiewicz G. L. Perlovich M. Koźbiał 《Journal of solution chemistry》1999,28(6):731-745
Solubilities of tricyclic analogs of acyclovir have been determined in water at 25, 35, and 45°C and in octanol, water-saturated octanol, and octanol-saturated water at 25°C. Octanol-water partition coefficients were determined at 25°C. Melting temperatures and molar enthalpies of fusion were measured. Activity coefficients in water, octanol, and in aqueous octanol solutions were determined and are discussed. The effect of hydrophilic and hydrophobic substituents in the tricyclic analogs on their thermodynamic properties are discussed. The standard Gibbs energy of transfer between the saturated phases were found to correlate with known values of the melting point of the solvents and the solubilities of the solute. For a number of the compounds examined, correlations between the minimum inhibitory concentration against the herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), varicella-zoster virus (VZV), thymidine kinase-deficient (TK–) strains of VZV and
were established. Detailed conclusions have been derived concerning the relationships between the structure and the thermodynamic parameters of the compounds examined. 相似文献
4.
Adam S. Paziak Lech Celewicz Krzysztof Ciszewski Krzysztof Golankiewicz 《Journal of mass spectrometry : JMS》1993,28(5):643-646
The electron impact mass spectra of 6-methyltetrazolo[1,5-c]pyrimidin-5(6H)-one, its 7- and 8-methyl derivatives, three 8-halo derivatives and two related nucleosides are reported. On the basis of the high-resolution data and detected metastable ions, the fragmentation routes of their molecular ions are proposed. Coexistence of the tautomeric forms of the title compounds of cyclic (tetrazole) or linear (azide) structure can be suggested owing to the fragmentation pathways identified for the bases. Decomposition of the related nucleosides lies in the breaking of nucleoside bonds to produce the appropriate base and sugar fragments. 相似文献
5.
Ivan Leban Boenna Golankiewicz Joanna Zeidler Gerald Giester Joe Kobe 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o133-o135
In the title compound, C13H13N5O4·H2O (4,5′‐cyclowyosine·H2O), the cyclization forces a syn arrangement of the aglycon with respect to the sugar moiety. The ribofuranose part of the molecule displays a β‐d configuration with an envelope C1′‐endo pucker. The molecules are arranged in columns along the short a axis and are linked to water molecules through O—H?O and O—H?N hydrogen bonds. 相似文献
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7.
Adam S. Plaziak Jaroslaw Spychala Krzysztof Golankiewicz 《Journal of mass spectrometry : JMS》1991,26(12):1092-1094
N(Pyrimidin-2-yl)-glycine, -alanine and -phenylalanine (1-3) and their methyl esters (4-6) were investigated using electron impact (EI) mass Spectrometry. The results showed that EI-induced decomposition occurs on the carboxylic group or involves the loss of R2OH. In contrast to earlier investigations on N-(pyrimidin-4-yl)amino acids, elimination of water (in 1-3) or methanol (in 4-6) was found to be of EI-induced nature. The loss of 'COOH from M+ of ester 4 suggests the occurrence of a skeletal rearrangement leading to the isomeric N-methylamino acid. 相似文献
8.
Kinga Suwiska Boenna Golankiewicz Wojciech Zielenkiewicz 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):767-769
The biologically important molecule tricyclic acyclovir, presented here as 3‐[(2‐hydroxyethoxy)methyl]‐6‐methyl‐3H‐imidazolo[1,2‐a]purin‐9(5H)‐one dihydrate, C11H13N5O3·2H2O, shows conformational flexibility, which is observed in the solid state as two symmetrically independent molecules with different side‐chain conformations. Additionally, one of these molecules exhibits side‐chain disorder, such that there are three different conformations in the crystal. Water molecules found in the crystal form (H2O)8 clusters which are located between molecules of tricyclic acyclovir. The complex hydrogen‐bond network formed between water and tricyclic acyclovir in the solid state may be related to the solvation of the molecules in solution. 相似文献
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B. Golankiewicz A. Zielenkiewicz J. Zeidler W. Zielenkiewicz 《Journal of Thermal Analysis and Calorimetry》1995,45(4):667-673
2′3′-dideoxyinosine (ddI) and 2′3′-dideoxyadenosine (ddA) are known to exhibit relatively selective activityvs. HIV strains in cell cultures and low toxicityin vivo; ddI has been approved for the treatment of HIV infection in humans. It is therefore interesting to determine the thermodynamic properties of aqueous solutions of these compounds. For this purpose, we determined their apparent molar volumesV ? and heat capacitiesC P?. The preliminary measurements of interaction of these compounds with peptides were made. The volume and molar heat capacities of transfer of ddI and ddA from aqueous solutions to glycyl-glycine (Gly-Gly) ones were calculated. For both compounds the significant values ofC P?3,tr which depended on the concentration of Gly-Gly were observed. 相似文献