An efficient ten-step synthesis of deazathiamin is described. The synthesis starts from commercially available a-acetyl-g-butyrolactone and proceeds via deamination of the key aminothiophene 6. The Gewald synthesis of thiophenes is shown to give a mixture of isomeric products with the unsymmetric ketone used here and so a modified procedure giving a single isomer is developed.
Department of Chemistry
University of Cambridge