What is a derivative of urea, C3H4N2O2, obtained from allantion, as a white, crystalline substance, with a sweetish taste; -- called also glycolyl urea called?

hydantoin — A derivative of urea, C3H4N2O2, obtained from allantion, as a white, crystalline substance, with a sweetish taste; -- called also glycolyl urea. (Webster's 1913.)

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