Phosphorylation of Biologically Active Analogs of Riboflavin

SummarySeveral analogs of riboflavin selected because of their exceptional biological activity in the rat have been studied as substrates for rat hepatic flavokinase. All of the analogs were phosphorylated, but the rate of phosphorylation showed no correlation with type of activity or potency for these activities. Phosphorylation of a flavin analog may be a prerequisite for significant biological activity but phosphorylation of a flavin does not insure that the substance will be biologically active in the whole animal.