184 research outputs found

    A 100 éves röntgendiffrakció a gyógyszerkutatåsban

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    SzilĂĄrdfĂĄzisĂș szupramolekulĂĄris reakciĂłk = Solid state supramolecular reactions

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    ElƑállĂ­tottunk 24 vegyĂŒletet, ezek közĂŒl 17 kristĂĄlyszerkezetet hatĂĄroztunk meg. 6 esetben figyeltĂŒnk meg Piedfort kĂ©pzƑdĂ©st, hĂĄrom esetben talĂĄltunk asszociĂĄtumot. A C60 Ă©s C70 kokrisztallizĂĄciĂłja egy esetben Ășj mĂłdosulatot, a p-Br es p-Cl vegyĂŒletek esetĂ©ben a fullerĂ©n Ășj komplexĂ©t, illetve zĂĄrvĂĄnyĂĄt adta. A trisz(p-jĂłdfenoxi)-triazin a MagyarorszĂĄgon mĂ©rt legkisebb szerves kristĂĄly (10 mikron). Ab initio szerkezetmeghatĂĄrozĂĄsi mĂłdszert alkalmaztunk (''charge-flipping''). A vendĂ©g-molekulĂĄk cserereakciĂłinak elemi lĂ©pĂ©sre bontĂĄsakĂ©nt a kristĂĄlyszerkezet ''bomlĂĄsĂĄt'' eliminĂĄciĂłs reakciĂłkĂ©nt lĂĄtjuk. A metil-etil-ketont (MEK) tartalmazĂł izoftĂĄlsav-szĂĄrmazĂ©k kristĂĄly hasonlĂł rendezetlensĂ©get mutat, mint az etilacetĂĄt-MEK keverĂ©k, szemben a rendezett dietil-ketonbĂłl növesztettel. A C--H ... O hidrogĂ©nhidak szeepĂ©t taglalĂł cikk, ill. predikciĂł eredmĂ©nyekĂ©nt megkezdtĂŒk foszfolĂ©nek szerkezetvizsgĂĄlatĂĄt. ElsƑ eredmĂ©ny egy vĂ­z molekulĂĄt tartalmazĂł asszociĂĄtum izolĂĄlĂĄsa Ă©s leĂ­rĂĄsa. A Meloxicam:mannĂłz kokrisztallizĂĄciĂłbĂłl nyert aprĂł kristĂĄlyokat a drug triklin formĂĄjakĂ©nt azonosĂ­tottuk. SzilĂĄrdfĂĄzisĂș reakciĂłt igazoltunk ribĂłz szĂĄrmazĂ©kok Ă©s alkĂĄli sĂłk közt. A komponensek ƑrlĂ©sĂ©vel is igazoltuk, hogy e komplexek ''zöld kĂ©miai'' uton elƑállĂ­thatĂłak. Ezek nĂ©melyike Ă©lettani jelentƑsĂ©gƱ lehet. A szintĂ©ziseken tĂșl elvĂ©geztĂŒk 3 tucat kristĂĄly szerkezetmeghatĂĄrozĂĄsĂĄt. Eddig 14 cikk jelent meg (IF összeg kb. 30), tartottunk 4 meghĂ­vott elƑadĂĄst Ă©s közel egy tucat posztert. | We have prepared 24 new compound, 17 of which was characterized by XRD. In 6 cases we observed Piedfort formation, in 3 we found associations. Co-crystallization with C60 and C70 yielded to new polymorphs and new inclusions in the cases of the p-Br and p-Cl derivatives. Tris-p-iodophenoxy-triazine is the smallest organic crystal ever measured in Hungary (10 micron). We applied new ab initio structure solution methods (charge flipping). Guest exchange reactions were disassembled into elementary steps and decomposition of inclusions is seen as the elimination reactions do. An isophtalic acid derivative inclusion with methyl-ethyl keton shows similiar disorder to the one obtained from MEK / ethyl acetate mixture while diethyl keton inclusion is perfectly ordered. Apaper alluding to the role of C-H..O H-bridges and prediction led to structure determination of some phospholenes. Firts result was the isolation and description of a water adduct. Crystal structure of a cocrystallized meloxicam:mannose mixture was identified as the triclinic drug form. We confirmed a solid state reaction between riboise derivatives and alkaline salts. Milling of the components proved that these can be easily prepared by ''green chemistry''. Some of these might be physiological importance. Apart from the synthetic work we did about 3 dozens of crystal structure determinations, also published 14 papers (impact factor sum ca. 30) hitherto, had 4 invited lectures and some 12 posters

    PREPARATION AND INVESTIGATION OF TRIALKOXY-SILYL DERIVATIVES OF SATURATED CARBOXYLIC ACIDS

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    A study was carried out on the preparation of triethoxy-silyl derivatives of the allyl esters of several carboxylic acids. This has been achieved by the preparation of the allyl esters of carboxylic acids followed by the addition of triethoxy-silane, HSi(OCH₂ CH₃)₃ on the double bond of the allyl group. The new compounds were characterized by refractivity, density, boiling point, elemental analysis, lR and 1H-NMR spectroscopy methods

    Methods for easy recognition of isostructurality – lab jack-like crystal structures of halogenated 2-phenylbenzimidazoles

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    Easy recognition and numerical description of isostructurality; how different the similar structures can be; supramolecular aspects of isostructurality

    Conformational studies on substituted Δ-caprolactams by X-ray crystallography and NMR spectroscopy

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    The synthesis and conformational analysis of Δ-caprolactams containing a -COOMe group at the C-6 position is described. The influence of different C-2, C-6 and N substituents on ring conformation was studied using X-ray crystallography and NMR spectroscopy. The results provide evidence that all the analysed caprolactams adopt a chair type conformation with a planar lactam. In the 6-substituted caprolactam, the -COOMe residue prefers to reside in an equatorial position, but can be induced to occupy an axial orientation by the introduction of a bulky tert-butyloxycarbonyl (BOC) group on the lactam nitrogen or by C-2/C-3 ring desaturation. The BOC protected caprolactam was found to undergo exchange between two chair forms as detected by solution NMR, one with the C-6 ester equatorial (30%) and the other with it in the axial position (70%); the latter was observed by X-ray crystallography. For the C-2 dithiocarbamate substituted C-6 methyl ester seven-membered rings, a single chair form is observed for cis-isomers with both substituents equatorial. The analogous trans-isomers, however, exist as two chair forms in a 1 : 1 equilibrium ratio of 1,NC4 and 4C1,N conformers, where either substituent can occupy axial or equatorial positions. This journal i

    catena-Poly[[[bis­(thio­urea-ÎșS)copper(I)]-ÎŒ-thio­urea-Îș2 S:S] iodide acetonitrile hemisolvate]

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    The title complex, {[Cu(CH4N2S)3]I·0.5CH3CN}n, was formed by the reaction of CuI and thio­urea in acetonitrile. There are two independent CuI ions in the asymmetric unit which are coordinated by two terminal and two bridging thio­urea ligands to form a one-dimensional helical chain structure progagating in the a-axis direction. Each CuI ion is in a distorted tetra­hedral coordination environment. The crystal structure is stabilized by weak N—H⋯S and N—H⋯I hydrogen bonds

    Crystal structures and isometricity comparison of methylated bisphenol F derivatives

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    The syntheses and X-ray structures of three methylated bisphenol F derivatives and one respective analogue are reported. A special emphasis lies on the influence of methyl groups on the conformation of the common diphenylmethane scaffold. The introduction of four methyl groups to bisphenol F was found not to disturb its typical strong hydrogen bond network, and yet, to change the pattern of the aromatic interactions in the overall packing. According to the isometricity comparison, the addition of methyl groups to the diphenylmethane core has a greater influence on the conformation of the individual molecules, than the presence or absence of hydrogen bonding donors or acceptors. © 2013 Elsevier B.V. All rights reserved
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