Phenylethyl Resorcinol is also known as SymWhite 377 and was developed by Symrise researchers to serve as a lightening and brightening ingredient in skin care products, hair lightening products, and cosmetics. It is an antioxidant that is considered effective in influencing the formation of pigmentation, and therefore able to lighten the skin, according to research. It is a synthetic compound that is partially derived from natural lightening compounds found in scotch pine bark, and is considered a reliable whitening agent. According to studies published by Symrise (no independent studies were found), when directly compared to B-Arbutin, SymWhite 377 (Phenylethyl Resorcinol) was shown to be over one hundred times as effective at lightening hair, and when tested in vivo on skin that had not been exposed to light, 0.5% concentrations of SymWhite 377 proved to be more effective than 1.0% kojic acid.cts.