[′meth·ə‚lȯl ′rī·bə‚flā·vən] (organic chemistry) An orange to yellow powder, soluble in water; used as a nutrient and in medicine.
methylol riboflavin
meth·yl·ol ri·bo·fla·vin
a mixture of methylol derivatives of riboflavin formed by the action of formaldehyde on riboflavin in weakly alkaline solution; it has the same action as riboflavin, but is preferred for parenteral administration.