89371-44-8Relevant articles and documents
Kinetic study of the alkaline degradation of imidapril hydrochloride using a validated stability indicating HPLC method
Abdulla, Shabaan A.,Frag, Eman Y.,Ahmed, Heba E.
, p. 69239 - 69250 (2016/08/05)
An aqueous alkaline degradation study was performed for imidapril hydrochloride (IMD) drug in the presence of its degradation products and an isocratic stability indicating method was presented using a HPLC technique. The separations were performed using an ACE Generix 5C8, 150 × 4.6 mm column and a mobile phase consisting of buffer solution (0.1 M potassium dihydrogen phosphate and 0.02 M tetra-N-butyl ammonium hydrogen sulphate of pH = 4.5 with 1 N HCl) and acetonitrile 60:40 (v/v). The wavelength of the detector was adjusted at 210 nm. The method showed high sensitivity concerning accuracy, precision, linearity and specificity within the acceptable range from 0.1 to 100 μg mL-1 and the limit of quantification was found to be 0.0211 μg mL-1 for IMD. The proposed method was used to determine the drug in its pharmaceutical formulation and to investigate the degradation kinetics of the drug's alkaline-stressed sample. The reactions were found to follow a first-order reaction. The activation energy could also be estimated. The optimized stability indicating HPLC method was validated according to ICH guidelines.
Hydrolytic profile for ester- or amide-linkage by carboxylesterases pI 5.3 and 4.5 from human liver
Takai, Satomi,Matsuda, Ayuka,Usami, Yoshiko,Adachi, Tetsuo,Sugiyama, Tadashi,Katagiri, Yoshihiro,Tatematsu, Masae,Hirano, Kazuyuki
, p. 869 - 873 (2007/10/03)
Carboxylesterases (EC 3.1.1.1) from human liver were purified using Q- Sepharose, Sephadex G-150, isoelectrofocusing and Con A-Sepharose. The calculated molecular mass of the pI 5.3 enzyme was 120 kDa and 61 kDa from the results of Sephadex G-150 gel filtration and SDS-polyacrylamide gel electrophoresis (PAGE), respectively, suggesting that this enzyme is a dimer. On the other hand, carboxylesterase pI 4.5, with a molecular-mass of 64 kDa, was a monomer. The activities of both enzymes were inhibited by typical serine enzyme inhibitors. Amino acid sequence analysis of the purified enzymes pI 5.3 and 4.5 showed high homology with rabbit carboxylesterase form 1 and 2, respectively. The results also suggested that carboxylesterase pI 5.3 is identical to the deduced amino acid sequence from cDNA for HUI, and that carboxylesterase pI 4.5 is identical to the deduced amino acid sequence from the cDNA registered as human carboxylesterase (hCE-2) in GenBank. We first purified carboxylesterase pI 4.5 and investigated its hydrolytic activity upon various drugs. The two enzymes differed in substrate specificity. Prodrugs of angiotensin-converting enzyme inhibitors, such as delapril and imidapril, were converted to active metabolites by carboxylesterase pI 5.3, but not by carboxylesterase pI 4.5. The hydrolysis velocity of temocapril by carboxylesterase pI 5.3 was 12-fold faster than by carboxylesterase pI 4.5. In contrast, aspirin oxybutynin and procaine were hydrolyzed by only carboxylesterase pI 4.5. We also found that an amide- linkage in drugs, except for that in aniracetam was not a good substrate for the two enzymes. Consequently, carboxylesterases pI 5.3 and 4.5 maybe involved in the metabolism of various drugs containing an ester-linkage.
Process for preparing optically active 2-oxoimidazolidine derivatives
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, (2008/06/13)
Disclosed are a process for preparing an optically active 2-oxoimidazolidine derivative of the formula: STR1 wherein R1 represents hydrogen atom or a lower alkyl group, according to the process described in the specification; and a 3-acyl-2-oxo
