Tiazofurin is a drug which acts as an inhibitor of the enzyme IMP dehydrogenase. Tiazofurin and its analogues were under investigation for potential use in the treatment of cancer,[1] though side effects such as pleuropericarditis and a flu-like syndrome precluded further development. They also show antiviral effects and may be reevaluated as potential options in the treatment of newly emerging viral diseases.[2]
The treatment of 1-O-Acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose [6974-32-9] (1) with trimethylsilyl cyanide gives 2,3,5-Tri-O-benzoyl-beta-D-ribofuranosyl cyanide [23316-67-8] (2). Treatment with hydrogen sulfide led to (2R,3R,4R,5R)-2-((Benzoyloxy)methyl)-5-carbamothioyltetrahydrofuran-3,4-diyl dibenzoate, PC10907289 (3). Cyclization with Ethyl bromopyruvate [70-23-5] (4) led to 2-(2,3,5-Tri-O-benzoyl-beta-D-ribofuranosyl)-4-thiazolecarboxylic Acid Ethyl Ester [60084-09-5] (5). Removal of the protecting groups with sodium methoxide afforded 2-beta-D-Ribofuranosyl-4-thiazolecarboxylic Acid Ethyl Ester [95936-53-1] (6). Amide-ester interchange by treatment with dry ammonia completed the synthesis of Tiazofurin (7).