Wyniki wyszukiwania - BazTech

1

Zastosowanie algorytmów mrówkowych w poszukiwaniu optymalnych połączeń

Baszun M., Główka M.

Logistyka

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2009

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nr 3

CD-CD

PL

W pracy przeanalizowano podstawowe możliwości jakie stwarza użycie modyfikacji znanego algorytmu mrówkowego przy rozwiązywaniu zagadnień poszukiwania optymalnych połączeń. Wykonano implementacje programistyczne oraz przeprowadzono symulacje z użyciem tego oprogramowania. Wnioski z symulacji mogą być przydatne przy doborze ilościowych parametrów precyzujących działanie danej odmiany algorytmu. Przykładowe obliczenia wskazują na dobrą efektywność czasową znajdowania rozwiązań np. zadania komiwojażera lub zagadnień marszrutyzacji. Wyniki wskazują na możliwości aplikacyjne w ogólnie rozumianych zagadnieniach transportowych w tym optymalizowanie połączeń w transporcie pojazdowym oraz w sieciach teleinformatycznych.

EN

In the paper ant class algoriths modifications were analyzed from application point of view for logistics problems. Software implementations were been done, and various simulations were executed with the software. The results could be usefull for detailing of the algorithms from point of view of specific applications. The exampled discussion were aimed to travelling problem and routing problems. The conclusions could be usefull at vehicle transport or teleinformatic logistics.

2

Geometry of Lidocaine-like Molecules: 3. Structure of a Potent Antiarrhythmic Agent: 2-Methyl-2-(1-morpholinyl)-N-(2,6-dimethylphenyl) acetamide

Główka M., Olczak A., Białasiewicz W., Kwapiszewski W.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 6

1079-1085

EN

Crystal structure of an alanylyl analog of lidocaine with its amine function incorporated into morpholine ring and showing promising type I antiarrhythmic activity was studied in form of free base and hydrochloride. Crystal data: free base a = 9.498(2), b = 11.716(2), c = 13.497(2); hydrochloride a = 10.820(1), b = 11.971(3), c = 12.564(1); both P212121 (Z = 4); R1 = 0.039 and 0.037, respectively. Substitution at C alfa and incorporation of N amine atom into the aliphatic morpholinic ring significantly change conformational preference around C alfa-C(O) and C alfa-N(ring) bonds, as compared with parent lidocaine. The most interesting conformational change observed was that the title molecule in the protonated form (being probably the biologically active) has gauche orientation of _N-H(amine) bond in relation to C=O group, while all other structures have different orientations, either antiperiplanar or synperiplanar (unprotonated lidocaine only). And the two groups are crucial for hydrogen bonds formation with a perspective receptor of type I antiarrhythmics.

3

Geometry of alfa-Diaryl Type CH-NH Acids of Pharmacological Interest. Crystal Structures of alfa-(4-Chlorophenyl)- and alfa-(2,4-Dichlorophenyl-alfa-2-pyrazilideneacetonitrilles

Główka M., Olczak A., Bojarska J., Szczesio M., Kozłowska K., Foks H.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 8

1275-1284

EN

alfa-Diarylacetonitriles represent a very interesting model for studying the structure-activity relationship, due to restricted freedom of conformational diversity and, on the other hand, a very wide range of biological activities, including analgesic, non-narcotic antiinflammatory and antirheumatic. The two studied representatives have in the crystal state very uniform molecular structures, which may be characterized by a dihedral angle between the two aromatic rings, being 77 graduate in 4-chlorophenyl; 74 graduate and 80 graduate in 2,4-dichlorophenyl derivative, respectively. Despite the presence of groups capable of weak C-H hydrogen bonds formation there is only one short C-H...X contact (X = N in 4 position of the pyrazinyl ring) of 2.40 ?, being significantly shorter than the sum of van der Waals radii of respective atoms. The contact found in the 2,4-dichlorophenyl derivative crystal is in accord with CH-NH proton transfer observed in these compounds.

4

Synthesis and structure of Two thiocarboxypyrazolic Acid Derivatives

Główka M., Błaszczyk M., Prentjas Ch., Kovala-Demertzi D.

Polish Journal of Chemistry

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2004

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Vol.78 /nr 11-12

2013-2022

EN

Two thiocarboxypyrazolic acid amide derivatives were obtained unintentionally in a reaction of thiosemicarbazone with 2-acetylbutyrolactone, and structures of the final products have been determined by X-ray diffraction. Due to conjugation of the thioamide group with the planar pyrazolic ring, the molecule is flat, except 2-hydroxylethyl chain, accidentally adopting similar conformation in the two studied molecules. Also similar is the packing, despite different hydrogen bonding schemes, resulting from the different number of donoric H atoms and the presence of an additional water molecule in the second compound. The mechanism of the reaction is suggested.

5

Synthesis and crystal structure of 2,3,4-tri-0-acetyl-B-D-xylose 1-phosphorothioselenoate

Kudelska W., Olczak A., Główka M., Jankowski S.

Polish Journal of Chemistry

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1999

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vol. 73 nr 3

487-492

EN

Ambident anion derived from phosphorothioselenoates was glycosylated with1,2,3,4-terta-O-acetyl-b-D-xylopyranose in the presence of boron trifluoride etherate to yield Se-xylosyl and S-xylosyl phosphorothioselenoates. Structures of the products were established on the basis of selective oxidation. 31P NMR, 1H NOE studies and unambiguously by X-ray diffraction.

6

Crystal and molecular structures of 1,1-bis(methylthio)-4-(2-pyridyl)-2,3,5-triaza-1,3-pentadiene and its 5-phenyl derivative

Główka M., Martynowski D., Olczak A., Kozłowska K., Ołubek Z., Orlewska C., Foks H.

Polish Journal of Chemistry

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1999

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vol. 73 nr 5

845-851

EN

Structures of the two dimethylthiomethylene-2-pyridinecarboxamide hydrazones have been examined spectroscopially and by X-ray diffraction to establish the dominant tautometric form and conformation. The two crystal structures are very similar with approximately planar conformation and intramolecular hydrogen bond between 4-imine group as hydrogen donor and pyridyl N atom as an acceptor. Several significant differences found may be easily explained by phenyl substitution in one of the compounds. The benzene ring in compound 2 is twisted by about 40o in relation to the mean molecular plane due to packing forces. An interesting feature of the structures is the deviation of the pyridyl ring by 11-14o from the mean 2,3,5-triaza-1,3-pentadiene plane in the two structures, despite the intramolecular hydrogen bond spanning the two fragments. It agrees with the elongation of C(4)-pyridine bond to 1.488 A, which corresponds with the lack of conjugation between p electrons of the pyridine ring and a lone pair at adjacent N(4) atom.

7

Synthesis and X-ray studies of derivatives of 1,2,4-triazolidine-3-thiones

Korzycka M., Główka M., Janicka J.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 1

73-77

EN

Reactions of 2,4-disubstituted thiosemicarbazides with acetone catalyzed by sulfuric acid gave cyclic 1,2,4-triazolidine-3-thione derivatives. The same reaction with no catalyzer gave open-chain compounds. Synthesis and X-ray studies of some 1,2,4-triazolidine-3-thiones are described.