103129-82-4Relevant articles and documents
Enantiomeric separation of racemic amlodipine by sequential fractional crystallization through formation of diastereomeric salt solvates and co-crystals of solvate-like compounds with specific structure — A tandem resolution
Bánhegyi, Dorottya Fruzsina,Madarász, János,Pálovics, Emese,Szolcsányi, Dóra
, (2021/11/22)
A new resolution method of racemic amlodipine has been developed. The racemic compound is reacted in a suitable solvent with 0.25-mol equivalent of (R,R)-tartaric acid. After the decomposition of the diastereomeric salt, the remaining racemic fraction is precipitated with half-equivalent of fumaric acid, and the pure amlodipine enantiomer is obtained. A quarter equivalent of the same resolving agent, (R,R)-tartaric acid has been also added to the mother liquor to obtain the other enantiomer. The advantage of this method is that both of the enantiomers of amlodipine could be obtained with high enantiomeric excess with the same resolving agent. The racemic excess can also be isolated and re-resolved. Achiral reagents (urea and thiourea) have been added to the resolving agent. These neutral additives are incorporated as co-crystals in the structure of the diastereomeric salts. The used solvate-former solvents and achiral additives are structurally similar, and their presence can enable the fractional separation of the diastereomers. In addition, the racemate, the enantiomers, and some intermediate salts with high diastereomeric excess obtained in the resolution process of amlodipine have been also subjected to thermal (DSC, TG/DTA-EGA-MS, and -FTIR), analytical (FTIR spectroscopic), and structural (XRD) comparisons, which indicate that the key-intermediate crystalline diastereomeric salts—as solvates and co-crystals—inherit a kind of structural similarity from their related additives—solvents (DMF, DMAA, and DMSO) or (thio)ureas, respectively.
Enantioseparation of racemic amlodipine using immobilized ionic liquid by solid-phase extraction
Liu, Min,Liu, Zhong-Qian,Zhu, Hai,He, Chao-Hong,Wu, Ke-Jun
, p. 1062 - 1071 (2020/05/06)
In this paper, a novel l-glutamate based immobilized chiral ionic liquid (SBA-IL (Glu)) was prepared by chemical bonding method and applied as a solid sorbent for chiral separation of amlodipine. The performance of SBA-IL (Glu) was investigated for the absorption of (S)-amlodipine and separation of amlodipine enantiomer. The static experiment showed that equilibrium adsorption was achieved within 80 minutes, and the saturation adsorptions capacity was 12 mg/g. The complex was then packed in a glass chromatographic column for the separation of amlodipine and the enantiomeric excess (%ee) of (S)-amlodipine reached 24.67%. The immobilized ionic liquids exhibit good reusability, and the separation efficiency remains 18.24% after reused five times, which allows potential scale-up for the chiral separation of amlodipine.
Enantioseparation of chiral pharmaceuticals by vancomycin-bonded stationary phase and analysis of chiral recognition mechanism
Li, Jiaxi,Liu, Ruixia,Wang, Liyang,Liu, Xiaoling,Gao, Hongjie
, p. 236 - 247 (2019/02/01)
The drug chirality is attracting increasing attention because of different biological activities, metabolic pathways, and toxicities of chiral enantiomers. The chiral separation has been a great challenge. Optimized high-performance liquid chromatography (HPLC) methods based on vancomycin chiral stationary phase (CSP) were developed for the enantioseparation of propranolol, atenolol, metoprolol, venlafaxine, fluoxetine, and amlodipine. The retention and enantioseparation properties of these analytes were investigated in the variety of mobile phase additives, flow rate, and column temperature. As a result, the optimal chromatographic condition was achieved using methanol as a main mobile phase with triethylamine (TEA) and glacial acetic acid (HOAc) added as modifiers in a volume ratio of 0.01% at a flow rate of 0.3?mL/minute and at a column temperature of 5°C. The thermodynamic parameters (eg, ΔH, ΔΔH, and ΔΔS) from linear van 't Hoff plots revealed that the retention of investigated pharmaceuticals on vancomycin CSP was an exothermic process. The nonlinear behavior of lnk′ against 1/T for propranolol, atenolol, and metoprolol suggested the presence of multiple binding mechanisms for these analytes on CSP with variation of temperature. The simulated interaction processes between vancomycin and pharmaceutical enantiomers using molecular docking technique and binding energy calculations indicated that the calculated magnitudes of steady combination energy (ΔG) coincided with experimental elution order for most of these enantiomers.