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July 29, 1939


JAMA. 1939;113(5):417. doi:10.1001/jama.1939.02800300047014

Clinically active vitamin K has been obtained principally from putrefied fish meal and alfalfa meal. In 1933 Anderson and Newman1 isolated a pigment from human tubercle bacilli which they designated phthiocol and the chemical constitution of which was determined as 2-methy1-3-hydroxy-1,4-naphthoquinone. The synthetic preparation of this quinone was tested by Almquist and Klose,2 who found that it possessed antihemorrhagic activity similar to that of vitamin K. The term phthiocol however has not been adopted generally by all other American or foreign investigators of this field or by the Council on Pharmacy and Chemistry. The preparation and purification of crystalline concentrates have proceeded rapidly and purified products have been announced almost simultaneously in many different laboratories. From Europe in March of this year a report appeared by Dam, Karrer and their colleagues3 on the isolation of vitamin K from alfalfa. There seems to be now general agreement that