131490-70-5Relevant academic research and scientific papers
Process for the preparation of 9-substituted guanine derivatives
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, (2008/06/13)
A process for the preparation of 9-substituted quanine derivatives of general formula (I), in which R is C1 -C4 -alkyl optionally substituted with one or more hydroxy groups, or R is (α), benzyl, ribosyl, 2'-deoxyribosyl or (CH2)n -OR1 where n is 1 or 2, and R1 is CH2 CH2 OH or (β) or salts thereof, in which a 1-substituted5-(thiocarbamoyl)amino-1H-imidazole-4-carboxamide of general formula (III), where R has the same meaning as in formula (I), is cyclized: a) by treatment with a heavy metal salt of the group of Cu-, Ag-, Pb- and Hg-salts in an aqueous alkaline medium containing at least for equivalents of OH-ions at a temperature form about 0° C. to the reflux temperature, or b) by treatment with a peroxy compound in an aqueous alkaline medium at a temperature of about 0°-30° C., whereafter (I) is isolated by treatment with a acid and, if desired, is converted into a salt. The invention further comprises intermediates for use in the preparation of the above-mentioned compounds.
