125602-71-3Relevant academic research and scientific papers
Identification, Characterization and HPLC Quantification of Process-Related Impurities in Bepotastine Besilate Bulk Drug
Zhang, Chaowei,Han, Chengqun,Sun, Lili,Yu, Jinlong,Zou, Qiaogen
, p. 12 - 22 (2020)
Bepotastine besilate (here after referred to as BTST), chemically known as ({d(S)4[4[(4chlorophenyl) (2pyridyl) methoxy] piperidino} butyric acid monobenzene sulphonate), is a second-generation antihistamine drug. To the best of our knowledge, no studies concerning the isolation or identification of process-related impurities have been reported so far. The current study reports the development and validation of a stability-indicating RP-HPLC method for the separation and identification of 5 potential impurities in bepotastine besilate. In this experiment, the structures of 3 process-related impurities were found to be new compounds. They were characterized and confirmed by NMR and MS spectroscopy analyses. These 3 new compounds were proposed to be (S)-4-[(phenyl)-2-pyridinylmethoxy]-1-piperidinebutanoic acid,(Imp-A); 4-[(S)-(4-chlorophenyl)-2-pyridinylmethoxy]-1- piperidinebutyric acid, N-oxide (Imp-B) and (S)-4-[(4- chlorophenyl)-2-pyridinylmethoxy]-1-piperidylethane (Imp-C). In addition, an efficient optimized chromatographic method was performed on a Shimadzu Inertsil C8-3 column (150 mm×4.6 mm, 3 μm) to separate and quantify these 5 impurities. It was using 15 mmol ammonium formate buffer in water (pH adjusted to 3.8 with formic acid) and acetonitrile as the mobile phase in gradient mode. The method was developed to separate and quantify these 5 impurities obtained in the range of 0.05-0.75 μg/mL. It was validated and proven to be selective, accurate and precise and suitable. It is the first publication of identification and characterization data of the 3 new compounds. It is also the first effective HPLC method for separation and quantification of all of process-related impurities in bepotastine besilate.
Total synthesis method of bestatin
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Paragraph 0020; 0050; 0064-0066; 0066; 0080-0081, (2021/10/11)
The method comprises the following steps: (4 - chlorophenyl) (2 - pyridyl) - methanol as a starting raw material, and sequential addition reaction. Examples of the etherification reaction include a deprotection reaction, a chiral resolution, a condensation reaction, a hydrolysis reaction, and the like. The synthesis method has the advantages of cheap and easily available raw materials, no need of expensive chiral catalysts, simpler synthesis method, mild conditions, less side reactions and low cost.
METHOD FOR MAKING PIPERIDINE DERIVATIVE INTO RACEMATE
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Paragraph 0072, (2019/02/07)
PROBLEM TO BE SOLVED: To provide a method for making efficiently a (R)-piperidine derivative into a racemate, and a method for producing a (S)-piperidine derivative from the racemate. SOLUTION: A method for producing a piperidine derivative of a racemate
IMPROVED PROCESS FOR THE MANUFACTURE OF BEPOTASTINE AND ITS BESILATE SALT
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, (2019/05/02)
The present invention discloses a process for preparation of Bepotastine and its Besilate salt of formula I with good yield and purity. The invention also describes a process for recycle and reuse of the Ethyl-4-hydroxy piperidine-1-carboxylate from the aqueous medium after isolating the 2-[(S)-(4-Chlorophenyl)(piperidin-4- yloxy)methyl]pyridine, for subsequent batches in the production of Ethyl 4-[(4- Chlorophenyl)(pyridin-2-yl)methoxy]piperidine-1-carboxylate. The invention further discloses novel intermediates, viz., 2-[Chloro(4- chlorophenyl)methyl]pyridine hydrochloride and bis{2-[(S)-(4- Chlorophenyl)(piperidin-4-yloxy)methyl]pyridine} Dibenzoyl tartrate, useful in the preparation of Bepotastine and its Besilate salt.
Iridium-Catalyzed Highly Enantioselective Transfer Hydrogenation of Aryl N-Heteroaryl Ketones with N-Oxide as a Removable ortho-Substituent
Liu, Qixing,Wang, Chunqin,Zhou, Haifeng,Wang, Baigui,Lv, Jinliang,Cao, Lu,Fu, Yigang
, p. 971 - 974 (2018/02/23)
A highly enantioselective transfer hydrogenation of non-ortho-substituted aryl N-heteroaryl ketones, using readily available chiral diamine-derived iridium complex (S,S)-1f as a catalyst and sodium formate as a hydrogen source in a mixture of H2O/i-PrOH (v/v = 1:1) under ambient conditions, is described. The chiral aryl N-heteroaryl methanols were obtained with up to 98.2% ee by introducing an N-oxide as a removable ortho-substituent. In contrast, no more than 15.1% ee was observed in the absence of an N-oxide moiety. Furthermore, the practical utility of this protocol was also demonstrated by gram-scale asymmetric synthesis of bepotastine besilate in 51% total yield and 99.9% ee.
A stable besylate bepotastine crystal and its preparation method
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Paragraph 0054-0055, (2018/02/04)
The invention discloses a stable bepotastine besilate crystal in novel crystal form through a recrystallization method. The obtained bepotastine besilate crystal is confirmed through X-ray powder diffraction and infrared spectrum. Stability contrast experiments prove that the provided bepotastine besilate crystal has extremely high stability, and both bulk drug and preparation of the bepotastine besilate crystal have stability obviously better than that of existing bepotastine besilate crystals.
Asymmetric syntheses method of ophthalmologic drug bepotastine besilate
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, (2017/09/01)
The invention relates to an asymmetric synthesis method of an ophthalmologic drug pylistramine besylate. The method concretely comprises the following steps: oxidizing (4-chlorophenyl)(2-pyridyl)methanone to obtain (4-chlorophenyl)(2-pyridyl)ketone-N-oxide; carrying out asymmetric transfer hydrogenation reduction on the (4-chlorophenyl)(2-pyridyl)ketone-N-oxide through using a complex of monosulfonyl chiral diamine and metallic ruthenium, rhodium and iridium as a catalyst and a sodium formate or formic acid and triethylamine mixture or isopropanol as a hydrogen source in order to prepare (S)-(4-chlorophenyl)(2-pyridyl)methanol-N-oxide; reducing the (S)-(4-chlorophenyl)(2-pyridyl)methanol-N-oxide to prepare (S)-(4-chlorophenyl)(2-pyridyl)methanol; and condensing the (S)-(4-chlorophenyl)(2-pyridyl)methanol and ethyl 4-(4-bromopiperidine-1-yl)butyrate to obtain the ophthalmologic drug pylistramine besylate. The total yield is 61.6%.
Salt-forming method of bepotastine besilate
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Paragraph 0021, (2016/12/22)
The invention discloses a salt-forming method of bepotastine besilate, wherein the method includes the steps of: 1) adding benzenesulfonic acid monohydrate to organic alcohol, stirring the solution until the benzenesulfonic acid is completely dissolved for later use; 2) dissolving (+)-(S)-4-{4-[(4-chlorophenyl)(2-pyridyl)methoxyl]piperidyl}n-butyric acid in organic alcohol, controlling the temperature at -20 - 20 DEG C and stirring speed at 50-200 rpm, adding a less amount of bepotastine besilate crystal seeds, dropwisely adding the benzenesulfonic acid organic alcohol solution, and then continuously stirring the solution with temperature maintained; and 3) performing crystallization for 1-5 h and filtering the solution, pour-washing a filter cake with the organic alcohol, and performing pressure reduced drying to obtain the bepotastine besilate. The method can form uniform granules in the product, is high in yield, has good impurity removal effect and excellent operability, is low in production cost and high in efficiency, and is suitable for industrial production.
Improved preparation method of bepotastine besilate
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Paragraph 0047, (2016/10/09)
The invention relates to an improved preparation method of bepotastine besilate.The improved preparation method of bepotastine besilate includes the following steps that firstly, 2-[(4-chlorophenyl)(4-piperidinyloxy)methyl]pyridine and a resolving agent a
