94666-07-6Relevant academic research and scientific papers
Continuous-Flow Synthesis of (R)-Tamsulosin Utilizing Sequential Heterogeneous Catalysis
Saito, Yuki,Nishizawa, Ken,Laroche, Benjamin,Ishitani, Haruro,Kobayashi, Shū
, (2022/02/16)
We describe the continuous-flow synthesis of (R)-tamsulosin, a blockbuster therapeutic drug employed for dysuria associated with urinary stones and benign prostatic hyperplasia, by utilizing sequential heterogeneous catalysis. Two heterogeneous catalysts have been developed for the synthesis, and the key step involves reductive amination of nitriles using dimethylpolysilane-modified Pd on activated carbon/calcium phosphate. Overall, (R)-tamsulosin was obtained in 60 % yield and 64 % ee (99 % ee after recrystallization) in a flow stream through four catalytic transformations without the need for the isolation or purification of any intermediates or byproduct.
Method of resolving tamsulosin enantiomer
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, (2017/08/29)
The invention relates to a method of resolving tamsulosin enantiomer, and in particular, relates to a method of resolving tamsulosin, represented as the formula (I), into an R-enantiomer and an S-enantiomer. The method includes the steps of: (a) dissolving a solid mixture of (R)-tamsulosin free alkali and (S)-tamsulosin free alkali in a solvent and performing a reaction to the free alkalis with camphor-10-sulfonic acid to form a solution containing a pair of diastereomeric camphor-10-sulfonates of tamsulosin, and then preferentially precipitating one diastereomeric camphor-10-sulfonate of the tamsulosin from the solution containing a pair of the diastereomeric camphor-10-sulfonates of tamsulosin, thereby forming a precipitate, in which one diastereomer is enriched, and a solute, in which the other one diastereomer is enriched; and (b) from one of the precipitate and the solute, releasing tamsulosin free alkali to obtain optical-rotation-enriched tamsulosin free alkali. The method has excellent technical performance.
Process for the resolution of racemic (R,S) -5-(2-(2-(2- ethoxyphenoxy) ethylamino)propyl)-2-methoxybenzene sulfonamide (tamsulosin), its novel R and S isomers and their salts and processes for their preparation
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Page/Page column 6, (2010/10/20)
An improved process is described to resolve a racemic mixture in any proportion of 5-(2-(2-(2-ethoxyphenoxy)ethylamino)propyl)-2-methoxy benzene sulfonamide as a free base or some of its salts, with BPA either S or R form to obtain enantiomerically highly pure R and S-isomer as a well characterized free base or as a salt of the title compound. Also described are novel R and S-isomers of 5-(2-(2-(2-ethoxyphenoxy) ethylamino)propyl)-2-methoxy benzene sulfonamide and their salts and the processes for their preparation.
Process for the separation of R(-)-and S(+)-5-[2-[[2-(2-ethoxyphenoxy)ethyl]amino]propyl]-2-methoxybenzenesulfonamide
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Page 5, (2010/02/10)
The process for separating the R(?)- and S(+)-5-[2-[[2-(2-ethoxyphenoxy)ethyl]amino]propyl]-2-methoxybenzene-sulfonamide enantiomers comprises (a) reacting a mixture of said enantiomers with an optically active organic acid to form diastereoisomeric salts with said enantiomers, where in said diastereoisomeric salts have different solubility and can be separated by crystallization; (b) separating the diastereoisomeric salt mixture enriched in the salt of one of the enantiomers; and (c) releasing said salts to obtain the R(?)or S(+) enantiomer. The R(?)-5-[2-[[2-(2-ethoxyphenoxy) ethyl]amino]propyl]-2-methoxybenzenesulfonamide enantiomer has α-adrenergic blocking activity and is useful as an antihypertensive agent suitable for the treatment of congestive heart failure and benign prostatic hypertrophy.
