220329-19-1Relevant articles and documents
A left hand chlorine paipai Si Tingfenoak acid preparation method of the
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Paragraph 0143; 0144; 0161; 0172; 0187; 0202, (2017/08/25)
The invention discloses a preparation method of levo cloperastine fendizoate, which comprises the following steps: carrying out nucleophilic substitution reaction on 4-chlorobenzhydrol and 2-chloroethanol in a benzene organic solvent, so that an intermediate product is obtained; reacting the intermediate product with piperidine, so that racemic cloperastine is obtained; resolving the racemic cloperastine by using a resolving agent in a fatty alcohol solvent, so that levo cloperastine is obtained; and carrying out salt forming reaction on the levo cloperastine and a fendizoic acid, so that levo cloperastine fendizoate is obtained, wherein the resolving agent is an R-substituted dibenzoyl-L-tartaric acid, and R refers to alkyl, alkoxy, -Cl, -F, -Br or -H. In the method provided by the invention, in a fatty alcohol solvent, an R-substituted dibenzoyl-L-tartaric acid is adopted as a resolving agent for carrying out resolving on racemic cloperastine, and the resolving yield is high, so that the obtained levo cloperastine fendizoate has high optical purity, and has a high product yield.
