42137-88-2Relevant articles and documents
Chelate ring sequence effects on thermodynamic, kinetic and electron-transfer properties of copper(II/I) systems involving macrocyclic lisands with S4 and NS3 donor sets
Galijasevic, Semira,Krylova, Ksenia,Koenigbauer, Michael J.,Jaeger, Gregory S.,Bushendorf, Jeffery D.,Heeg, Mary Jane,Ochrymowycz, Leo A.,Taschner, Michael J.,Rorabacher, David B.
, p. 1577 - 1586 (2003)
The kinetic behavior of electron-transfer reactions involving several copper(II/I) complexes has previously been attributed to a dual-pathway "square scheme" mechanism in which changes in the coordination geometry occur sequentially, rather than concertedly, with the electron-transfer step. In the case of 14-membered macrocyclic quadridentate ligand complexes studied to date, the major geometric change appears to be the inversion of two coordinated donor atoms during the overall electron-transfer process. However, the relative importance of these two inversions has been a matter of speculation. In the current investigation, a comparison is made of Cu(II/I) systems involving two pairs of ligands with S4 and NS3 donor sets: 1,4,8,11-tetrathiacyclotctradecane ([14]aneS4-a); 1,4,7,11-tetrathiacyclotetradecane ([14]aneS4-b); 1,4,8-trithia-11-azacyclotetradecane ([14]aneNS3-fl); and 1,7,11-trithia-4-azacyclotetradecane ([14]aneNS3-b). In each pair of ligands, isomer a has the common chelate ring size sequence 5,6,5,6 while isomer b has the sequence 5,5,6,6. A crystal structure for [CuII([14] aneNS3-&)(H2O)](ClO4)2 demonstrates that, when coordinated to Cu(II), the b isomers stabilize the relatively rare ligand conformation designated as conformer II in which one donor atom is oriented opposite to the other three relative to the plane of the macrocycle. This eliminates one of the donor atom inversion steps which normally occurs during Cu(II/I) electron transfer. The copper complexes formed with these a and b isomers are examined in terms of (i) their CuIIL and CuIL stability constants, (ii) their CuIIL formation and dissociation rate constants, (iii) their CuII/IL redox potentials and (iv) their apparent electron self-exchange rate constants. Of the two donor atom inversions which occur in the case of the a-isomer complexes, the specific donor atom inversion which is common to the b-isomer complexes is judged to exhibit the larger energy barrier. Thus, it is presumed to represent the rate-limiting process responsible for the onset of "gated" electron transfer in previous studies on a-isomer complexes. The Royal Society of Chemistry 2003.
POLYMORPHIC FORM OF 5-(4-[4-(5-CYANO-1H-INDOL-3-YL) BUTYL] PIPERAZIN-1-YL) BENZOFURAN-2-CARBOXAMIDE AND PROCESS FOR PREPARING THEREOF
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Paragraph 0085, (2014/07/08)
The present invention provides a solid state Form-Z of 5-(4-[4-(5-cyano-1H-indol-3-yl)butyl]piperazin-1-yl)benzofuran-2-carboxamide. The present invention also provides a process for preparing Form-Z of 5-(4-[4-(5-cyano-1H-indol-3-yl)butyl]piperazin-1-yl)benzofuran-2-carboxamide comprising the steps of i) reacting solid state form of 5-(1-piperazinyl)benzofuran-2-carboxamide or its salts with 3-(4-chlorobutyl)-1H-indole-5-carbonitrile an organic solvent in presence of a base to obtain crude vilazodone free base; ii) purifying the crude vilazodone free base of step (i) in an organic solvent; iii) treating the purified vilazodone free base of step (ii) with an organic solvent to obtain solid state form-Z of vilazodone. The present invention further provides a pharmaceutical composition comprising a therapeutically effective amount of an amorphous form of vilazodone hydrochloride and use of solid state Form-Z of vilazodone for the treatment of major depressive disorders.
Structural analysis of bis-amidines and bis-nitriles in solid-state by combining NMR spectroscopy and molecular modeling
Zabiński, Jerzy,Maciejewska, Dorota,Ka?mierczak, Pawe?
experimental part, p. 132 - 140 (2009/10/01)
The paper presents the analysis of the structures of four novel sulfonamide-based bis-amidines, and four novel interesting intermediates leading to them, named bis-nitriles, in solid-state based on 13C CP/MAS NMR spectroscopy and theoretical calculations of shielding constants at DFT level of theory. We have observed double 13C resonances in solid-state spectra as compared with solution spectra. The considerations of experimental chemical shifts followed by shielding computations allowed us to define essential geometric details regarding the most probable conformations in solid-state. All compounds have one independent molecule in the asymmetric unit, and a main reason of splittings of NMR signals in solid-state is different orientation of alkoxy fragments (methyl groups and linker) with reference to benzene rings.
