Chemistry  of a color reaction of retinoic acid (vitamin A acid) in sulfuric acid.
D055598:Chemical Phenomena; D002621:Chemistry; D003124:Colorimetry / Q000379:methods; D013329:Structure-Activity Relationship; D013464:Sulfuric Acids; D014212:Tretinoin; D014801:Vitamin A / Q000031:analogs & derivatives
D013464:Sulfuric Acids; D014801:Vitamin A; D014212:Tretinoin