28118-33-4Relevant academic research and scientific papers
N′-(Arylsulfonyl)pyrazoline-1-carboxamidines as novel, neutral 5-hydroxytryptamine 6 receptor (5-HT6R) antagonists with unique structural features
Van Loevezijn, Arnold,Venhorst, Jennifer,Iwema Bakker, Wouter I.,De Korte, Cor G.,De Looff, Wouter,Verhoog, Stefan,Van Wees, Jan-Willem,Van Hoeve, Martijn,Van De Woestijne, Rob P.,Van Der Neut, Martina A. W.,Borst, Alice J. M.,Van Dongen, Maria J. P.,De Bruin, Natasja M. W. J.,Keizer, Hiskias G.,Kruse, Chris G.
experimental part, p. 7030 - 7054 (2011/12/15)
The 5-HT6 receptor (5-HT6R) has been in the spotlight for several years regarding CNS-related diseases. We set out to discover novel, neutral 5-HT6R antagonists to improve off-target selectivity compared to basic amine-con
SULFONYLPYRAZOLE AND SULFONYLPYRAZOLINE CARBOXAMIDINE DERIVATIVES AS 5-HT6 ANTAGONISTS
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Page/Page column 21-22, (2008/06/13)
This invention concerns sulfonylpyrazoline carboxamidine derivatives as antagonists of 5-HT6 receptors, to methods for the preparation of these compounds and to novel intermediates useful for their synthesis. The invention also relates to the uses of such compounds and compositions, particularly their use in administering them to patients to achieve a therapeutic effect in Parkinson's disease, Huntington's chorea, schizophrenia, anxiety, depression, manic depression, psychoses, epilepsy, obsessive compulsive disorders, mood disorders, migraine, Alzheimer's disease, age related cognitive decline, mild cognitive impairment, sleep disorders, eating disorders, anorexia, bulimia, binge eating disorders, panic attacks, akathisia, attention deficit hyperactivity disorder, attention deficit disorder, withdrawal from abuse of cocaine, ethanol, nicotine or benzodiazepines, pain, disorders associated with spinal trauma or head injury, hydrocephalus, functional bowel disorder, Irritable Bowel Syndrome, obesity and type-2 diabetes. The compounds have the general formula (1), wherein the symbols have the meanings given in the description.
Stereoselective ring-opening polymerization of a racemic lactide by using achiral salen- and homosalen-aluminum complexes
Nomura, Nobuyoshi,Ishii, Ryohei,Yamamoto, Yoshihiko,Kondo, Tadao
, p. 4433 - 4451 (2008/02/09)
Highly isotactic polylactide or poly(lactic acid) is synthesized in a ring-opening polymerization (ROP) of racemic lactide with achiral salen- and homosalen-aluminum complexes (salenH2 = N,N′-bis(salicylidene) ethylene-1,2-diamine; homosalenH2 = N,N′-bis(salicylidene) trimethylene-1,3-diamine). A systematic exploration of ligands demonstrates the importance of the steric influence of the Schiff base moiety on the degree of isotacticity and the backbone for high activity. The complexes prepared in situ are pure enough to apply to the polymerizations without purification. The crystal structures of the key complexes are elucidated by X-ray diffraction, which confirms that they are chiral. However. analysis of the 1H and 13C NMR spec tra unambiguously demonstrates that their conformations are so flexible that the chiral environment of the complexes cannot be maintained in solution at 25°C and that the complexes are achiral under the polymerization conditions. The flexibility of the back-bone in the propagation steps is also documented. Hence, the isotacticity of the polymer occurs due to a chain-end control mechanism. The highest reactivity in the present system is obtained with the homosalen ligand with 2.2-dimethyl substituents in the backbone (ArCH=NCH2CMe2CH2N=CHAr), whereas tBuMe2Si substituents at the 3-positions of the salicylidene moieties lead to the highest selectivity (Pmeso,= 0.98; T m = 210°C). The ratio of the rate constants in the ROPs of racemic lactide and L-lactide is found to correlate with the stereoselectivity in the present system. The complex can be utilized in bulk polymerization, which is the most attractive in industry, although with some loss of stereoselectivity at high temperature, and the afforded polymer shows a higher melting temperature (Pmeso = 0.92, Tm up to 189°C) than that of homochiral poly(L-lactide) (Tm = 162-180°C). The "livingness" of the bulk polymerization at 130°C is maintained even at a high conversion (97-98%) and for an extended polymerization time (1-2 h).
Resonanzstabilisierung von Alkylradikalen durch zwei geminale Cyangruppen
Pakusch, Joachim,Beckhaus, Hans-Dieter,Ruechardt, Christoph
, p. 1191 - 1198 (2007/10/02)
Effects of Substituents on the Strength of C-C bonds, 10. - Resonance Stabilization of Alkyl Radicals by Two Geminal Cyano groups The activation parameters of the homolytic cleavage of the Cq-Cq bonds of several dialkylated malonodinitriles (2-5) and of 1,1,2,2-tetracyanoethane (7) and the heat of dissociation of 6 in solution have been determined.Together with the ground state strain of the radical precursor (obtained from the heats of combustion or EFF calculations) the steric influence on the dissociation process has been determined.The resonancestabilization energy of α,α'-dicyanoalkyl radicals then calculated was (12.4 +/- 0.9) kcal/mol.This result is discussed within the concept of capto-dative stabilization.The destabilizing interaction of two geminal cyano groups is apparently the same in the ground state of 2-7 and the radicals generated from them.
Phase Transfer Catalysis without Solvent: Selective Mono- or Di-alkylation of Malononitrile
Diez-Barra, Enrique,Hoz, Antonio de la,Moreno, Andres,Sanchez-Verdu, Prado
, p. 2589 - 2592 (2007/10/02)
Monoalkyl and symmetrical or unsymmetrical dialkylmalononitriles have been prepared selectively by phase transfer catalysis in the absence of solvent.Exclusive formation of a particular compound is achieved in all cases except for benzylmalononitrile 2f (79percent) and prop-2-ynylmalononitrile 2g (62percent).
The Synthetic Potential of the Isocyanide-Cyanide Rearrangement
Meier, Michael,Ruechardt, Christoph
, p. 1 - 4 (2007/10/02)
Excellent chemical and optical yields (>96percent retention) of cyanides are achieved by vapor phase thermolysis or short contact flow thermolysis of isocyanides. trans-2-Butenyl isocyanide rearranges without concomitant allylic isomerization to trans-2-butenyl cyanide.Optically active 1-(formyloxymethyl)-2-phenylethyl cyanide is obtained from optically active L-phenylalanine as a new type of chiral pool synthon.
