- KIO4-mediated Selective Hydroxymethylation/Methylenation of Imidazo-Heteroarenes: A Greener Approach
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Herein, we report a KIO4-mediated, sustainable and chemoselective approach for the one-pot C(sp2)?H bond hydroxymethylation or methylenation of imidazo-heteroarenes with formaldehyde, generated in situ via the oxidative cleavage of ethylene glycol or glycerol (renewable reagents) through the Malaprade reaction. In the presence of ethylene glycol, a series of 3-hydroxymethyl-imidazo-heteroarenes was obtained in good to excellent yields. These compounds are important intermediates to access pharmaceutical drugs, e.g., Zolpidem. Furthermore, by using glycerol, bis(imidazo[1,2-a]pyridin-3-yl)methane derivatives were selectively obtained in good to excellent yields.
- Braga, Antonio Luiz,Franco, Marcelo Straesser,Rafique, Jamal,Saba, Sumbal
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p. 18454 - 18460
(2021/07/21)
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- 2-ARYL IMIDAZO[1,2-A]PYRIDINE-3-ACETAMIDE DERIVATIVES, PREPARATION METHODS AND USE THEREOF
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Disclosed are 2-arylimidazo[1,2-a]pyridine-3-acetamide derivatives represented by formula I, their tautomer, racemate or optical isomer, their pharmaceutically acceptable salt, or their solvates, wherein R1, R2, R3 and R4 are defined as in the specification. Preparation methods of said compounds and use of said compounds in treating and/or preventing central nervous system disease associated with TSPO functional disorder
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Paragraph 0053
(2013/05/09)
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- PROCESS FOR PREPARING ZOLPIDEM AND ITS INTERMEDIATE
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The present invention relates to an improved process for the preparation of 6- methyl-2-[4-methylphenyl]imidazo[l,2-a]pyridine-3-N,N-dimethyl acetamide having formula (1). The compound of formula (1) has adopted name "Zolpidem". The present invention also relates to novel intermediate of the formula (2) and a process for its preparation.Wherein R represents methyl, ethyl, propyl, butyl, isopropyl, isobutyl or tertiary butyl group. The novel intermediate of formula (2) is used in preparation of Zolpidem having formula (1). Zolpidem is useful in the treatment of anxiety, sleep disorders and convulsion.
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Page/Page column 11; 13-14; 15-17
(2009/03/07)
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- PROCESS FOR PREPARING ZOLPIDEM
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A process for preparing zolpidem.
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Page/Page column title page; sheet 1; 6
(2010/11/25)
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- A structure-activity relationship study of the affinity of selected imidazo[1,2-a]pyridine derivatives, congeners of zolpidem, for the ω1-subtype of the benzodiazepine receptor
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A series of 6-substituted 2-aryl-N,N-dimethylimidazol [1,2-a]pyridine-3-acetamides, congeners of zolpidem and alpidem, was synthesized and tested in vitro for binding with the benzodiazepine receptor in the competition with 3H-zolpidem as an ω1-selective radioligand. Molecular electrostatic potential (MEP) and the HOMO and LUMO energies were calculated for the compounds by semi-empirical quantum chemistry methods. The lipophilicity parameter of the compounds, expressed as the logarithm of the octanol-water partition coefficient (log P), was calculated; alternatively, standard values of the Hansch hydrophobic substituent constants π were used. In agreement with earlier investigations on the benzodiazepine receptor ligands with a high preference for the ω1-subtype, a quantitative correlation of the biological data with molecular parameters has revealed a significant dependence (r=0.954) of the binding affinity (IC50) on the deepest MEP minimum, in this case associated with the amide carbonyl oxygen atom. The lipophilicity parameters were found to be of lower significance.
- Lange,Karolak-Wojciechowska,Wejroch,Rump
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