catechol molecule pattern seamless

pattern seamless background repeat catechol molecule simple vector isolated black carbon formula model molecular oxygen science antioxidant atom chemical chemistry cycle education hydrocarbon hydrogen phenol reagent reductant structure allergen atomic benzenediol c6h6o2 cyclic dihydroxybenzene element illustration isomer macromolecule organic compound pyrocatechol study bond chain enzyme ortho photodeveloper structural synthetic white crystal biochemistry