Given the task definition and input, reply with output. In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

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

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