A Simple and High-Yield Route to N-9-purinyl-acetic Acid Derivatives Coupled with Amino Acids

A facile route to synthesize amide type N-9-purinyl-acetic acid derivatives both in guanine and hypoxanthine series is described. The regioselective alkylation of the 6-chloro-purine derivatives followed by their conversion into guanine or hypoxanthine nucleus in mild acidic conditions, are the key steps that allow the efficient preparation of compounds with an acetic function coupled with various amino acids.