97845-60-8Relevant articles and documents
Preparation method of penciclovir
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, (2020/02/14)
The invention discloses a preparation method of penciclovir. An existing synthetic route mainly has the following defects that the N-7 site by-products need to be removed through column chromatography, a large amount of three wastes are generated, and the yield of N-9 site products is not high. According to the technical scheme adopted by the invention, the preparation method comprises the following steps: carrying out alkylation on 2-amino-6-chloropurine and triethyl bromopropane under an alkaline condition to introduce an N-9 site side chain, carrying out decarboxylation and transesterification in a methanol solution of sodium methoxide to generate the 2-amino-6-chloro-9-(3,3-dimethoxycarbonyl-1-propyl)purine; then reducing the 2-amino-6-chloro-9-(3,3-dimethoxycarbonyl-1-propyl)purine togenerate 2-amino-6-chloro-9-(3-hydroxymethyl-4-hydroxy-1-butyl)purine with sodium borohydride; and finally, directly hydrolyzing under acidic conditions to obtain penciclovir. According to the method, the target product is obtained by directly hydrolyzing the reduction product, ester group protection and deprotection are not needed, and the method has the advantages of few reaction steps, good product quality, simplicity and convenience in operation, suitability for industrial production and the like.
Method for preparing 2-amino-6-chloro-9-(4-acetoxy-3-acetoxymethylbutyl)purine
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, (2018/08/03)
The invention relates to a method for preparing 2-amino-6-chloro-9-(4-acetoxy-3-acetoxymethylbutyl)purine. The method comprises the following steps: reacting 1,3-dichloro-2-propanol with acetic acid to obtain 1,3-diacetoxy-2-propanol, brominating the 1,3-diacetoxy-2-propanol to obtain 1,3-diacetoxy-2-bromopropane, and reacting the 1,3-diacetoxy-2-bromopropane with zinc powder to obtain 1,3-diacetoxy-2-propylzinc bromide, and then performing a Negishi Coupling reaction on the 1,3-diacetoxy-2-propylzinc bromide and chloro-9-bromoethylpurine to obtain 2-amino-6-chloro-9-(4-acetoxy-3-acetoxymethylbutyl)purine. The obtained 2-amino-6-chloro-9-(4-acetoxy-3-acetoxymethylbutyl)purine has an HPLC purity of 99.5% or more, and can be used for producing famciclovir and penciclovir.
A process for the manufacture of famciclovir using phase-transfer catalysts
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Page/Page column 5, (2008/06/13)
The invention relates to a process for the preparation of Famciclovir, which comprises the preparation of a compound of formula (II) wherein X is a halogen atom by reaction of a compound of formula (III) with a compound of formula (VII) wherein L is a leaving group, in the presence of a catalytic amount of a quaternary ammonium salt, followed by hydrogenation of compound (II) to Famciclovir.