- Preparing method of levalbuterol
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The invention provides a preparing method of levalbuterol (5) shown in the formula (5). The preparing method includes the steps that a compound shown in the formula (1) reacts with formaldehyde and acetic anhydride to obtain a compound (2) shown in the formula (2); a compound (3) shown in the formula (3) is obtained through bromination; a compound (4) shown in the formula (4) is obtained through asymmetric reduction; the compound finally reacts with tert-butylamine, and the protecting group is removed to obtain levalbuterol (5) shown in the formula (5). The preparing method is simple in path, easy to operate, mild in reaction condition, high in yield and stereoselectivity and low in industrial production, and has short steps and high practical application value and social economic benefits.
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Paragraph 0064; 0065; 0066; 0067; 0068; 0069; 0070-0081
(2017/04/29)
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- Synthesis of the β2 Agonist (R)-Salmeterol Using a Sequence of Supported Reagents and Scavenging Agents
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(Matrix Presented) The enantioselective synthesis of (R)-salmeterol has been achieved by using a sequence of supported reagents and sequestering agents. The saligenin core was installed by a regiospecific alkylation and a chiral auxiliary approach was employed to introduce the desired stereochemistry via a diastereoselective reduction.
- Bream, Robert N.,Ley, Steven V.,Procopiou, Panayiotis A.
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p. 3793 - 3796
(2007/10/03)
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- Esters
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The invention concerns di- and tri-esters derived from alkanoic, (cycloalkyl)alkanoic, benzoic or phenylalkanoic acids with N-(acylaminoalkyl)-dihydroxyphenylethanolamines, and pharmaceutically acceptable salts thereof; processes for their preparation and manufacture; and pharmaceutical compositions thereof. The esters are useful for the topical treatment of an area of inflammation affecting the skin of a warm-blooded animal. Representative esters of the invention are 1-[3,4-bis(pivaloyloxy)phenyl]-2-[2-(2-phenylacetamido)ethylamino]-ethanol, 1-[3,4-bis(pivaloyloxy)phenyl]-2-[1,1-dimethyl-2-(2-phenoxyacetamido)-ethylamino]-ethanol, and the hydrochlorides and hydrobromides thereof.
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