142678-35-1Relevant articles and documents
Biphasic recognition chiral extraction - Novel way of separating pantoprazole enantiomers
Liu, Jia-Jia,Liu, Chang,Tang, Ke-Wen,Zhang, Pan-Liang
, p. 599 - 607 (2014)
This paper presents a biphasic recognition chiral extraction system developed as a new chiral separation technology for the separation of pantoprazole enantiomers, combining a hydrophilic β-CD derivative in the aqueous phase and a hydrophobic tartaric acid in the organic phase which preferentially recognise the (R)-enantiomer and (S)-enantiomer, respectively. In this study, a number of factors which influence the efficiency of the extraction were investigated including types of organic solvents, β-CD and tartaric acid esters and their concentrations, pH and temperature. As a result, enantioselectivity for pantoprazole enantiomers can be improved up to 1.42 under optimised conditions; in addition, it is clear that the combined action of β-CD and tartaric acid esters leads to formation of the biphasic chiral extraction system with a stronger separation capacity than a monophasic chiral extraction system.
Method for preparing chiral sulfoxide drugs in water phase
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Paragraph 0053-0055, (2020/09/09)
The invention relates to the field of chiral drug preparation, in particular to a method for preparing chiral sulfoxide drugs in a water phase. The method for preparing the chiral sulfoxide drugs in the water phase comprises the following steps: using a hydrogen peroxide solution as oxidant, using a temperature-sensitive ferrocene chiral amino acid titanium complex as a catalyst and using prochiral thioether as a substrate in the pure water phase to perform an asymmetric oxidation reaction to synthesize the chiral sulfoxide drugs. The temperature-sensitive ferrocene chiral amino acid titaniumcomplex catalyst can be utilized to catalyze the asymmetric oxidation reaction of thioether in the pure water phase and has the characteristics of high catalytic efficiency and easy recovery of the catalyst.
Synthesis of Esomeprazole and Related Proton Pump Inhibitors through Iron-Catalyzed Enantioselective Sulfoxidation
Nishiguchi, Shigenobu,Izumi, Takuhiro,Kouno, Takayoshi,Sukegawa, Junpei,Ilies, Laurean,Nakamura, Eiichi
, p. 9738 - 9743 (2018/10/09)
We report here an application of iron catalysis for the kilogram scale asymmetric synthesis of a proton pump inhibitor, esomeprazole, in 87% yield and 99.4% ee by catalytic sulfoxidation with hydrogen peroxide using an iron salt/chiral Schiff base in combination with a carboxylate salt. Under similar reaction conditions, other proton pump inhibitors such as (S)-lansoprazole, (S)-rabeprazole, and (S)-pantoprazole, were also synthesized in high yield and ee. A carboxylate additive was crucial for the success of this reaction, and we consider that it coordinates to the active iron species, and it also acts as a hydrogen-bond acceptor to coordinate to the substrate through the imidazole NH.