THE CHEMISTRY OF THE "AMINOCHROMES": PART II. THE PREPARATION, PAPER CHROMATOGRAPHY, AND SPECTROSCOPIC PROPERTIES OF PURE ADRENOLUTIN; THE INFRARED SPECTRUM OF ADRENOCHROME

Abstract

The preparation of adrenolutin monohydrate in pure crystalline form has been carried out by the alkaline rearrangement of aqueous solutions of adrenochrome, prepared from the silver oxide oxidation of adrenaline in aqueous solution. An anion-exchange resin (Dowex-1 (Cl−)) was employed to remove inorganic contaminants from the reaction mixture prior to treatment with alkali. The pure anhydrous material has been prepared by the high vacuum sublimation of the monohydrate. The paper chromatographic, spectroscopic, and fluorimetric characteristics of adrenolutin have been investigated. On the basis of the infrared spectrum it is suggested that in the solid state, adrenolutin exists in the keto form, i.e. 2,3-dihydro-5,6-dihydroxy-N-methyl-3-ketoindole. The infrared spectrum of adrenochrome, in the solid state, agrees with the zwitterionic formulation suggested for this compound.