Methyl 3-[(1R)-3-[Bis(1-methylethyl)amino]-1-phenylpropyl]-4-hydroxybenzoate (2S,3S)-2,3-Bis(benzoyloxy)-butanedioic Acid; Methyl 3-[(1R)-3-[Bis(1-methylethyl)amino]-1-phenylpropyl]-4-hydroxybenzoate Dibenzoyl-D-tartaric Acid; 3-[(1R)-3-Bisisopropylamino-1-phenylpropyl-4-hydroxy Benzoic Acid Methyl Ester (2S,3S)-2,3-Bis(benzoyloxy)-butanedioic Acid