The production and purification of actinomycin B are described. Addition of dilute alkali to an alcoholic solution of actinomycin causes a marked hypsochromic effect which is reversible. The reaction obeys secondorder kinetics and is interpreted as a fission of the oxygen bridge of the phenoxazin-3-one nucleus, giving rise to a highly strained and non-planar quinone anil. The reverse reaction involves two stages ; ring closure and elimination of water. Isatin, another molecule which shows a hypsochromic shift in the spectrum after addition of alkali, is shown to possess spectral characteristics which differ from those of actinomycin in several respects.

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Optimum conditions have been determined for the preparation of various -fluoroalkylmagnesium halides. The effects of halogen and chain-length on the course of the reactions were investigated. A series of -fluorocarboxylic acids were prepared by carbonation of the Grignard reagents.