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1.
An enantioselective high-performance liquid chromatographic method, with precolumn derivatization with Marfey’s chiral reagent,
sodium 2,4-dinitro-5-fluorophenyl-l-alanine amide, has been developed for resolution of the enantiomers of a new antiepileptic drug, pregabalin, in the bulk
drug. The diastereomers of the pregabalin enantiomers were resolved to baseline on a reversed-phase ODS column with a 60:40
(v/v) mixture of aqueous 0.2% triethylamine (pH adjusted to 3.5 with dilute orthophosphoric acid) and acetonitrile as mobile phase.
Resolution between the diastereomers was not less than five. The method was extensively validated and proved to be robust.
The calibration plot was indicative of an excellent linear relationship between response and concentration over the range
750 (LOQ) to 7,500 ng L−1 for the R enantiomer. The limits of detection and quantification of the R enantiomer were 250 and 750 ng L−1, respectively, for an injection volume of 10 μL. Recovery of the R enantiomer from bulk drug samples of pregabalin ranged from 97.5 to 101.76%. Solutions of pregabalin in water and in the
mobile phase were found to be stable for at least 48 h. The method was found to be suitable and accurate for quantitative
determination of the R enantiomer in the bulk drug. It can be also used to test the stability of samples of pregabalin. 相似文献
2.
Amidoalkyl naphthols have been synthesized in high yields in the presence of 1-hexanesulphonic acid sodium salt as an inexpensive solid catalyst under solvent-free conditions and microwave-irradiation.This catalyst provides clean conversion;greater selectivity and easy workup make this protocol practical and economically attractive. 相似文献
3.
A rapid reversed-phase high-performance liquid chromatographic procedure is developed and validated for the resolution of
the cis-isomer of 1-[[p-[2-(3-ethyl-4-methyl-2-oxo-3-pyrroline-1-carboxamido) ethyl] phenyl] sulfonyl]-3-(trans-4-methylcyclohexyl) urea, a dopamine agonist in bulk drugs. The cis-isomer and glimepiride were baseline resolved on a Waters Symmetry column (50 × 4.6 mm, 3.5 μm) using a mobile phase system
containing water: tetrahydrofuran (75:25; v/v. The chromatographic resolutions between cis-isomer and glimepiride were found to be greater than two. The developed method was extensively validated and proved to be
robust. The limit of detection and the limit of quantification of cis-isomer were 500 and 1,500 ng mL−1, respectively, for 10 μL injection volume. The percentage recovery of the cis-isomer ranged from 97.3 to 102.0 in bulk drug samples of glimepiride. Glimepiride sample solution and mobile phase were found
to be stable for at least 48 h. The proposed method was found to be suitable and accurate for the quantitative determination
of the cis-isomer in bulk drugs. 相似文献
4.
Kiran F. Shelke Suryakant B. Sapkal Kirti S. Niralwad Bapurao B. Shingate Murlidhar S. Shingare 《Central European Journal of Chemistry》2010,8(1):12-18
A green, mild and efficient method for Knoevenagel condensation of 3-formylchromone/2-chlroquinoline-3-carbaldehyde with active
methylene compounds such as Meldrum’s acid/ethyl cyanoacetate using biosupported cellulose sulphuric acid (CSA) in the solid-state
by grinding under solvent-free condition has been developed. This method provides several advantages including environmental
friendliness, shor t reaction times, high yields and a simple work-up procedure. Moreover, the CSA was successfully reused
for four cycles without significant loss of activity. 相似文献
5.
Kirti S. Niralwad Bapurao B. Shingate Murlidhar S. Shingare 《Ultrasonics sonochemistry》2010,17(5):760-763
1-Hexanesulphonic acid sodium salt was found to be an efficient catalyst for the green synthesis of α-aminophosphonates by the coupling of aldehydes/ketone, an amine and triethyl phosphite under ultrasound irradiation at ambient temperature for appropriate time to furnish the desired product in good to excellent yield under solvent-free condition. This catalyst provides clean conversion; greater selectivity and easy workup make this protocol practical and economically attractive. 相似文献
6.
7.
S.A. Sadaphal P.D. Ghogare S.G. Gupta B.B. Shingate M.S. Shingare 《Arabian Journal of Chemistry》2012,5(2):257-261
Potential biologically active derivatives of arylhydrazotriazole (3a–l) were prepared by the condensation reaction of diazonium salts using various aromatic amines (1a–l) and 1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl) ethanones (2). The synthesized products were obtained in 75–85% yield. All the synthesized products were having good-excellent antifungal activity as compared with standard (Fluconazole and Ketoconazole) drugs. 相似文献
8.
Deepak V.Dekhane Shivaji S.Pawar Sunil V.Gupta Murlidhar S.Shingare Shivaji N.Thore 《中国化学快报》2010,21(5):519-523
<正>The first successful lithium bromide mediated solvent free condensation of arylenediamine and esters to obtain 2-substituted benzimidazole and imidazopyridine in good to excellent yields is described. 相似文献
9.
A. H. Kategaonkar S. B. Sapkal B. R. Madje B. B. Shingate M. S. Shingare 《Chemistry of Heterocyclic Compounds》2010,46(6):754-758
Some new 4,5-diphenyl-1H-imidazole derivatives were synthesized in good yields by treating various tetrazolo[1,5-a]quinolines with benzil and ammonium acetate in glacial acetic acid. 相似文献
10.
Shivaji S. Pawar Deepak V. Dekhane Shivaji N. Thore Murlidhar S. Shingare 《Journal of heterocyclic chemistry》2008,45(6):1869-1873
A novel approach for the Aza‐Michael addition reactions between various amines and α,β‐unsaturated esters, nitriles and ketones using N‐donor Ligand catalyst (3 mol %) is described. The reactions are carried out in aqueous media at an ambient temperature to afford the products in excellent yields. 相似文献