melatonin. pineal gland hormone. regulator of the circadian rhythm. dietary supplement. c13h16n2o2. structural chemical formula

abstract antioxidant atom atomic bio biochemistry bond c13h16n2o2 chain chem chemical chemistry circadian compound design desynchronosis dietary dream drug equation flat formula gland graphic hormone human icon infographic insomnia line medicine melatonin model molecular molecule night nutrient pineal regulator rhythm science shape sign sleep structure supplement symbol treatment vector