Abstract
In order to obtain lipid soluble vitamin B_2,riboflavin-2', 3'-dibenzoate, -4', 5'-dibenzoate, -2', 3'-dibutyrate, -4', 5'-dibutyrate, -2', 3'-dinicotinate and -4', 5'-dinicotinate were prepared via the O-isopropylidene derivatives. Migration of acyl group was observed in the riboflavin-2', 3'-diesters. Reaction of riboflavins with acyl chloride afforded 3-N-acyl derivatives. Using hog pancreatic lipase, enzymic hydrolysis of riboflavin diesters was examined. Of the riboflavin diesters prepared, 2', 3'-diesters are found to be more hydrolyzable than 4', 5'-diesters by the enzyme.
