50505-66-3Relevant articles and documents
Preparation method of high-optical-purity tamsulosin impurity
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Paragraph 0014-0016; 0017-0019; 0020-0022; 0023, (2020/06/16)
The invention discloses a preparation method of a tamsulosin impurity I (formula I) and salt thereof, an impurity II (formula II) and salt thereof, and an impurity III (formula III) and salt thereof.The optical purity of the impurity I and the salt thereof is not less than 95%, preferably not less than 99%, the optical purity of the prepared impurity II and the salt thereof is not less than 95%,the optical purity of the prepared impurity III and the salt thereof is not less than 95%, and the impurities and the salts thereof can be used as a tamsulosin impurity reference substance. In the preparation method of the tamsulosin impurity salt, the tamsulosin impurity I and L-(+)-tartaric acid are salified in an ethanol-water mixed solvent, so that the purity of the tamsulosin impurity I can be effectively improved, and the tamsulosin impurity I and the salt thereof with the optical purity not less than 99% can be obtained by refining with an ethyl acetate-ethanol solution.
PROCESS FOR THE SYNTHESIS OF ARFORMOTEROL
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Page/Page column 32, (2009/12/28)
The present invention provides a process for preparing a compound of formula (Vl) or a salt thereof, the process comprising: (i) reacting 4-methoxyphenyl acetone with an amine of formula (VIII) under conditions of reductive amination to produce a compound of formula (II) or a salt thereof, wherein there is no isolation of an imine intermediate formed during the reductive amination; (ii) condensing the compound (II) or the acid addition salt thereof with an α-haloketone of formula (III) to produce the compound of formula (IV); (iii) reducing the compound (IV) to a compound of formula (V); and (iv) reducing the compound (V) to the compound of formula (Vl), wherein the reduction is carried out in the presence of either (1 ) a hydrogen donating compound in the presence of a hydrogen transfer catalyst; or (2) ammonium formate using a hydrogenation catalyst, wherein: R1 and R2 are independently optionally substituted arylalkyl, and Hal is selected from chloro or bromo.
PROCESS FOR THE PREPARATION OF TAMSULOSIN AND INTERMEDIATES THEREOF
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Page/Page column 12-13, (2008/06/13)
A process for producing tamsulosin of formula (I) and pharmaceutically acceptable addition salts, thereof comprises the steps of : a) Reacting compound R,R-[2-(4-methoxy-phenyl)-1-methyl-ethyl]-(1-phenyl-ethyl)-amine of formula (II) or a salt thereof (II) with chlorosulfonic acid with or without an organic solvent, to obtain compound R,R-2methoxy-5-[2-(1-phenyl-ethylamino)-propyl]-benzenesulfonic acid of formula (III) b) Hydrogenolysis of compound R,R-2-methoxy-5-[2-(1-phenyl-ethylamino)-propyl]- benzenesulfonic acid of formula III or a salt thereof carried out in an alcohol in the presence of a palladium catalyst using hydrogen or a source of hydrogen, to obtain compound R-(-)-5-(2-amino-propyl)-2-methoxy-benzenesulfonic acid of formula (IV) c)Reacting primary amine R-(-)-5-(2-amino-propyl)-2-methoxy-benzenesulfonic acid of formula (IV), or a salt thereof, with a compound of formula (V) wherein X represents an halogen atom selected from the group consisting of C1;Br and I, to obtain 5- [(2R)-2-[2-(2-ethoxy-phenoxy)-ethylamino]-propyl]-2-methoxy-benzenesulfonic acid compound of formula (VI) d) Reacting compound of formula (VI) with an halogenating agent, to obtain the corresponding sulfonylchloride of formula (VII). e)Reacting compound VII with ammonia to obtain compound I.
