2,4-Imidazolidinedione, 5,5-bis(3,4,5-trihydroxyphenyl)- 5,5-Bis(3,4,5-trihydroxyphenyl)-2,4-imidazolidinedione 5,5-Bis(3,4,5-trihydroxyphenyl)hydantoin 74697-64-6