- THE STRUCTURES DIPOLE MOMENTS AND RELATIVE ENERGY OF THE CONFORMERS OF CYCLOBUTYL ACETYLENE BY MICROWAVE AND AB INITIO METHODS
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With the guidance of ab initio computations, the microwave spectra of axial and equatorial conformers of cyclobutyl acetylene have been identified and assigned.Dipole moment measurements yielded μa = 0.82(1) and μc = 0.09(2) D for the equatorial conformer and μa = 0.79(1) D and μ = 0.13(2) D for the axial conformer.Relative intesity measurements showed that the equatorial conformer was more stable by 282+/-35 cm-1.By combining ab initio results with the experimental rotational constants, the structures of the two conformers have been determined with a reliability and precision greater than possible from either method alone.
- Berry, Rajiv J.,Harmony, Marlin D.,Dakkouri, Marwan,Siam, Khamis,Schaefer, Lothar
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- Olefin-Migrative Cleavage of Cyclopropane Rings through the Nickel-Catalyzed Hydrocyanation of Allenes and Alkenes
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A nickel-catalyzed hydrocyanation triggered by hydronickelation of the carbon-carbon double bonds of allenes followed by cyclopropane cleavage is described. The observed regio- and stereochemistries in the products are strongly influenced by the initial hydronickelation step, and allenyl- and methylenecyclopropanes reacted smoothly to promote the cleavage of cyclopropane. In contrast, this cleavage was not observed with vinylidenecyclopropanes, because the initial hydronickelation does not give a suitable intermediate for cleavage of the cyclopropanes. (Figure presented.).
- Hori, Hiroto,Arai, Shigeru,Nishida, Atsushi
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supporting information
p. 1170 - 1176
(2017/04/13)
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- Difluorocyclobutylacetylenes as positive allosteric modulators of mGluR5 with reduced bioactivation potential
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Schizophrenia is a serious illness that affects millions of patients and has been associated with N-methyl-D-aspartate receptor (NMDAR) hypofunction. It has been demonstrated that activation of metabotropic glutamate receptor 5 (mGluR5) enhances NMDA receptor function, suggesting the potential utility of mGluR5 positive allosteric modulators (PAMs) in the treatment of schizophrenia. Herein we describe the optimization of an mGluR5 PAM by replacement of a phenyl with aliphatic heterocycles and carbocycles as a strategy to reduce bioactivation in a biaryl acetylene chemotype. Replacement with a difluorocyclobutane followed by further optimization culminated in the identification of compound 32, a low fold shift PAM with reduced bioactivation potential. Compound 32 demonstrated favorable brain uptake and robust efficacy in mouse novel object recognition (NOR) at low doses.
- Degnan, Andrew P.,Maxwell, Darrell,Balakrishnan, Anand,Brown, Jeffrey M.,Easton, Amy,Gulianello, Michael,Hanumegowda, Umesh,Hill-Drzewi, Melissa,Miller, Regina,Santone, Kenneth S.,Senapati, Arun,Shields, Eric E.,Sivarao, Digavalli V.,Westphal, Ryan,Whiterock, Valerie J.,Zhuo, Xiaoliang,Bronson, Joanne J.,Macor, John E.
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p. 5871 - 5876
(2016/12/06)
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- OXAZOLIDINONES AS MODULATORS OF MGLUR5
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The disclosure generally relates to compounds of formula I, including their salts, as well as compositions and methods of using the compounds. The compounds are ligands, agonists and partial agonists for the mGluR5 receptor and may be useful for the treatment of various disorders of the central nervous system.
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Page/Page column 30
(2015/04/28)
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- OXAZOLIDINONE HYDROXAMIC ACID COMPOUNDS FOR THE TREATMENT OF BACTERIAL INFECTIONS
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This invention pertains generally to treating bacterial infections using organic compounds of Formula I. In certain aspects, the invention pertains to treating infections caused by Gram-negative bacteria. (I) wherein X, Y, R1, R2, R3, R4 and R5 and defined herein.
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Page/Page column 187
(2015/05/19)
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- AZAINDOLE DERIVATIVES AS CFTR MODULATORS
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The present invention relates to modulators of ATP-Binding Cassette (“ABC”) transporters or fragments thereof, including Cystic Fibrosis Transmembrane Conductance Regulator (“CFTR”), compositions thereof, and methods therewith. The present invention also relates to methods of treating ABC transporter mediated diseases using such modulators.
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Page/Page column 27-28
(2009/10/17)
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- The cyclopropyl effect on the regioselectivity of coupling reactions involving the lithiation of 1-cyclopropyl-2-arylacetylenes
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The cyclopropyl effect controlled the regioselectivity of the cross coupling reactions of propargylic/allenylic metallic species with electrophiles affording alkynic cyclopropanes. It was proposed that the strain in cyclopropyl ring, which makes the formation of vinylidenecyclopropanes unfavorable, determined the regioselectivity. Control experiment of i-propyl, cyclobutyl, and cyclohexyl- phenylacetylenes were conducted to support the above speculation.
- Ma, Shengming,He, Qiwen
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p. 2769 - 2778
(2007/10/03)
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- Preparation of cycloalkylacetylene compounds using dialkylaminomagnesium halide or bis(dialkylamino)magnesium
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The process of invention reacts an alkynyl halide with a mixture that includes a dialkylaminomagnesium halide or a bis(dialkylamino)magnesium compound to produce a cycloalkylacetylene compound. Preferably, the dialkylaminomagnesium halide compound is of the general formula R 2 NMgX (where R is a linear, branched, or cyclic alkyl substituent or R 2 N represents a heterocyclic alkyl amine and X is Cl, Br, or I) and the bis(dialkylamino)magnesium compound is of the general formula (R 2 N) 2 Mg (where R is a linear, branched, or cyclic alkyl substituent or R 2 N represents a heterocyclic alkylamine). In a preferred method of the invention, the reaction is conducted at moderate temperatures for a period of about 12 to 24 hours. The reaction mixture preferably includes tetrahydrofuran (THF), or a hydrocarbon, or a hydrocarbonether mixture. The preferred compounds produced by this process are cycloalkylacetylene compounds having 5 to 20 carbons, such as cyclopropylacetylene and cyclobutylacetylene.
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- Flash Vacuum Pyrolysis of Stabilised Phosphorus Ylides. Part 1. Preparation of Aliphatic and Therminal Alkynes
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Thermal extrusion of Ph3PO from β-oxoalkylidenetriphenylphosphoranes 4 to give the alkynes 5, which under conventional pyrolysis conditions is restricted to cases in which R1 is an electron withdrawing group, has been successfully achieved for R1=H or alkyl by using FVP.The method allows convenient construction of multigram quantities of the alkynes 5 from alkyl halides 1 and allows convenient construction of multigram quantities of the alkynes 5 from alkyl halides 1 and acid chlorides 3 in three steps with good overall yields.Under the conditions used the ylides with R2 = cyclobutyl also undergo less of ethene to provide convenient access to the vinylalkynes 6.
- Aitken, R. Alan,Atherton, J. Ian
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p. 1281 - 1284
(2007/10/02)
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