Chemical reduction of pterins to dihydropterins as substrates for enzymatic reactions

Dihydropterins are important intermediates in various metabolic pathways, including the biosynthesis of tetrahydrofolate and tetrahydromethanopterin, a key coenzyme in the one-carbon metabolism of methanogenic Archaea. Some procedures for the reduction of pterins to dihydropterins may produce undesirable tetrahydropterin contaminants. This work describes a procedure for the rapid reduction of pterins to dihydropterins while minimizing tetrahydropterin production that may be particularly useful in producing substrates for enzyme reactions when the dihydropterin substrate cannot be purchased commercially.