vitamin b3 complex nicotinamide niacin and nicotinamide riboside chemical formulas

vitamin b3 niacin nicotinamide riboside nicotinamide complex vitamin formula chemical skeletal niacinamide nicotinic acid bionic nicotinic vitamer form amide pellagra medication drug dietary supplement prevention treatment medicine deficiency health care structure supplementation structural compound composition molecule organic substance molecular model science essential research chemistry pharmacy biochemistry flat isolated vector