- NMR Spectroscopy and Theoretical Calculations in the Conformational Analysis of 1-Methylpyrrolidin-2-one 3-Halo-derivatives
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This study reports the results of ab initio and density functional theory (DFT) electronic structure calculations as well as 3JHH experimental and calculated coupling constant data obtained in the investigation of the conformational equilibrium of 3-halo-derivatives of 1-methylpyrrolidin-2-one. The five-membered ring assumes an envelope conformation owing to the plane of formation of the O=C-N-R bond, with C4 forming the "envelope lid". When the conformation changes, the "lid" alternates between positions above and below the amide plane. The α-carbonyl halogen assumes two positions: a pseudo-axial and a pseudo-equatorial. In the gaseous phase, the calculations indicate that the pseudo-axial conformer is more stable and preferable going down the halogen family. Natural bond orbital analysis showed that electronic delocalization is significant only for the iodo derivative. In the other derivatives, the electrostatic repulsion between oxygen and the halogen determines the conformational equilibrium. When the solvated molecule was taken into account, the pseudo-equatorial conformer population increased with the relative permittivity of the solvent. This variation was strong in the fluoro derivative, and the preference was inverted. In the chlorine derivative, the two populations became closer in methanol and acetonitrile. In the bromine and iodine derivatives, the percentage of pseudo-equatorial conformer increased only slightly owing to the dipole moment of the conformation: the pseudo-equatorial conformation has a greater dipole moment and thus is stable in media with high relative permittivity.
- De Melo, Ulisses Zonta,Silva, Ra G. M.,Yamazaki, Diego A. S.,Pontes, Rodrigo M.,Gauze, Gisele F.,Rosa, Fernanda A.,Rittner, Roberto,Basso, Ernani A.
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p. 2111 - 2121
(2015/08/19)
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- CHEMICAL COMPOUNDS
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The invention relates to a novel group of compounds of Formula (I) or a salt thereof: wherein R1, A and HET-1 are as described in the specification, which may be useful in the treatment or prevention of a disease or medical condition mediated through glucokinase (GLK) such as type 2 diabetes. The invention also relates to pharmaceutical compositions comprising said compounds, methods of treatment of diseases mediated by GLK using said compounds and methods for preparing compounds of Formula (I).
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Page/Page column 37
(2008/12/06)
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- PRODUCTION METHOD OF HETEROCYCLIC MERCAPTO COMPOUND
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A method of the invention industrially produces heterocyclic mercapto compounds useful as raw materials or intermediates in the synthesis of medicaments or pesticides, or as permanent wave agent, with a high yield and high productivity using easily available starting materials. A heterocyclic mercapto compound represented by Formula (1) (wherein X represents any structure of -O-, -S-, -NH-, and -NR1-; R1 represents any of an alkyl group, alkoxy group and alkoxyalkyl group each having 1 to 6 carbon atoms; Y represents an oxygen atom, a sulfur atom or -NR2-; R2represents a hydrogen atom or alkyl group having 1 to 6 carbon atoms; and Z1 represents a divalent organic residue having at least one mercapto group) is produced by reacting a metal sulfide or a metal hydrosulfide with a compound represented by Formula (2) (wherein X and Y are as defined in Formula (1); and Z2 represents a divalent organic residue having at least one halogen group) in the presence of a solvent at a pH of 7.0 to 11.0.
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Page/Page column 47
(2008/06/13)
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- Rapid and catalyst-free α-halogenation of ketones using N-halosuccinamides in DMSO
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α-Halogenation of various carbonyl compounds such as β-keto-esters, cyclic ketones, and lactams with N-halosuccinamides (NBS, NCS, NIS) in the presence of DMSO proceeded very smoothly to give the corresponding α-monohalogenated products in good to excellent yields with high selectivity under catalyst-free conditions. Copyright Taylor & Francis Group, LLC.
- Sreedhar,Reddy, P. Surendra,Madhavi
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p. 4149 - 4156
(2008/03/13)
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- HAIR PROCESSING AGENT AND METHOD FOR PERMANENT WAVING HAIR
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Provided are hair processing agents capable of permanent waving hair even at a neutral to weakly acidic pH range that causes less irritation to the skin, and hair processing agents in which an unpleasant odor is masked. Hair processing agents contain at least one compound represented by the formula (2). Hair processing agents contain a compound of the formula (2) and at least one compound (ii) selected from thioglycolic acid, thiolactic acid, cysteine, acetylcysteine, cysteamine, acylcysteamine, salts thereof and ester derivatives thereof. Hair processing agents contain a compound of the formula (2), a surfactant and water, and are emulsified. Hair processing agents contain a compound of the formula (2) and a specific perfume. wherein X is a structure selected from -O-, -S-, -NH- and -NR1-; R1 is an alkyl group of 1 to 6 carbon atoms; Y is an oxygen atom or a sulfur atom; in the formula (1), Z is a divalent organic residue having at least one mercapto group; in the formula (2), R is a divalent organic residue optionally having a mercapto group; and R2 is a hydrogen atom or an alkyl group of 1 to 6 carbon atoms.
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Page/Page column 117
(2008/06/13)
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- A simple and efficient method for α-bromination of carbonyl compounds using N-bromosuccinimide in the presence of silica-supported sodium hydrogen sulfate as a heterogeneous catalyst
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α-Bromination of carbonyl compounds (cyclic and acyclic ketones, amides and β-ketoesters) has been achieved efficiently by treatment with N-bromosuccinimide (NBS) and catalyzed by silica-supported sodium hydrogen sulfate (NaHSO4?SiO2
- Das, Biswanath,Venkateswarlu, Katta,Mahender, Gurram,Mahender, Ibram
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p. 3041 - 3044
(2007/10/03)
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- Chemoenzymatic enantioselective synthesis of 3-hydroxy-2-pyrrolidinones and 3-hydroxy-2-piperidinones
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The enantioselective synthesis of 3-hydroxypyrrolidin-2-ones and 3-hydroxy piperidin-2-ones has been carried out in high enantiomeric excess employing immobilized lipase from Pseudomonas cepacia.
- Kamal, Ahmed,Ramana, K. Venkata,Ramana, A. Venkata,Babu, A. Hari
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p. 2587 - 2594
(2007/10/03)
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- Indium-mediated reductive dehalogenation of α-halocarbonyl compounds in water
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Reactions of various α-halocarbonyl compounds 1 with indium in the presence of a catalytic amount of sodium dodecyl sulfate in water were performed to afford the corresponding parent carbonyl compounds 2 in excellent yields. The Royal Society of Chemistry 2000.
- Park, Leeyoung,Keum, Gyochang,Kang, Soon Bang,Kim, Kwan Soo,Kim, Youseung
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p. 4462 - 4463
(2007/10/03)
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- Indole derivatives for the treatment of osteoporosis
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The invention relates to indole compounds, a process for preparing, pharmaceutical compositions containing the compounds and treating diseases associated with over activity of osteoclasts.
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- 3-hydroxy-N-methylpyrrolidone and preparation thereof
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The novel compound, 3-hydroxy-N-methylpyrrolidone, is effective as a transdermal enhancer for the absorption of drugs through the skin of humans and animals. The 3-hydroxy-N-methylpyrrolidone is prepared from delta-butyrolactone which is converted to methyl 2,4-dibromobutyrate, this intermediate is reacted with methylamine to form N-methyl-2,4-dibromobutyramide, this intermediate is converted to 3-bromo-N-methyl-2-pyrrolidone by ring closure, and the 3-bromo-N-methyl-2-pyrrolidone is reacted with an alkaline earth metal carbonate or alkaline metal carbonate to form 3-hydroxy-N-methyl-2-pyrrolidone.
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- Synthesis and antiinflammatory activities of 3-(3,5-di-tert-butyl-4-hydroxybenzylidene)pyrrolidin-2-ones
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A series of 3-(3,5-di-tert-butyl-4-hydroxybenzylidene)pyrrolidin-2-ones was synthesized and evaluated as candidate antiinflammatory/analgesic agents as well as dual inhibitors of prostaglandin and leukotriene synthesis. Some compounds that showed dual inh
- Ikuta,Shirota,Kobayashi,Yamagishi,Yamada,Yamatsu,Katayama
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p. 1995 - 1998
(2007/10/02)
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