Urocanic acid synthesis

A method of producing trans-urocanic acid, which involves treating D-glucose with aqueous ammonia and formalin in molar ratio D-glucose: aqueous ammonia: formalin equal to 1:24:2.7, in water in the presence of basic copper carbonate at temperature 85-90°C for 3 hours to form (1S,2S,3S)-1-(1H-imidazol-4-yl)-butane-1,2,3,4-tetrazole, which is extracted in form of a hydrochloride. Through periodate splitting in water, the obtained (1S,2S,3S)-1-(1H-imidazol-4-yl)-butane-1,2,3,4-tetrazole is converted at room temperature to 1H-imidazole-4-carbaldehyde, condensation of which, in acetic anhydride in the presence of anhydrous potassium acetate at temperature 120°C for 2 hours, leads to formation of trans-urocanic acid with subsequent extraction thereof from the reaction mass.