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Upstream product

• 127047-77-2 4-acetoxy-3-(acetoxymethyl)-1-iodobutane 
• 10310-21-1 2-Amino-6-chloropurin 
• 128139-38-8 Acetic acid 2-acetoxymethyl-4-methanesulfonyloxy-butyl ester 
• 126589-88-6 1,3-diacetoxy-2-(2-hydroxyethyl)propane 
• 126589-82-0 2-Acetoxymethyl-4-bromobut-1-yl acetate 
• 131266-10-9 2-acetoxymethyl-4-benzyloxybutyl acetate 
• 77661-80-4 2-(2-(benzyloxy)ethyl)propane-1,3-diol 
• 225111-63-7 diethyl <2-(1-ethoxyethoxy)ethyl>malonate 
• 225111-64-8 1-acetoxy-2-acetoxymethyl-4-(1-ethoxyethoxy)butane 

Relevant academic research and scientific papers

Convenient syntheses of 9-[4-hydroxy-3-(hydroxymethyl)butyl]guanine (penciclovir) and 9-[4-acetoxy-3-(acetoxymethyl)butyl]-2-amino-9h-purine (famciclovir)

Guanine 11 was converted, in a one pot reaction, into 2-amino-6-[(4- chlorophenyl)sulfanyl]purine 9a in 88% isolated yield. 4-Acetoxy-3- (acetoxymethyl)butanol 123 was prepared from 2-chloroethanol in five steps and in 46% overall yield. The mesylate ester of compound 23 reacted with 9a in the presence of potassium carbonate with a high degree of regioselectivity (89%) to give the N-9 alkylated product 26 which was isolated in 80% yield. Acidic hydrolysis of the latter compound 26 gave penciclovir 4 in virtually quantitative yield. Penciclovir 4 and famciclovir 5 were prepared from 2- amino-6-[(4-chlorophenyl)sulfanyl]purine 9a in four and five steps, respectively, by procedures involving initial alkylation with 1,2- dibromoethane. The overall yields obtained were 65 and ca. 60%, respectively.

A PROCESS FOR THE PREPARATION OF 2-ACETOXYMETHYL-4 HALO-BUT-1-YL ACETATES

A process for the preparation of 2- acetoxymethyl-4-halo-but-l-yl acetates (I) in which X is chlorine or bromine, which are useful intermediates for the preparation of antiviral medicaments such as Penciclovir and Famciclovir, comprising the opening of 3-hydroxymethyl-tetrahydrofuran (V) in the presence of an acylating agent and a Lewis acid selected from magnesium bromide and samarium triiodide.