However , two B vitamins , niacin and riboflavin , bind with adenine to form the essential cofactors nicotinamide adenine dinucleotide -LRB- NAD -RRB- and flavin adenine dinucleotide -LRB- FAD -RRB- , respectively .

However , two B vitamins , niacin and riboflavin , bind with adenine to form the essential cofactors NAD and FAD respectively .
