28.10.23

Chamomile Flowers
(CHAPTER V. The Flavone Group.)

The Natural Organic Colouring Matters
By
Arthur George Perkin, F.R.S., F.R.S.E., F.I.C., professor of colour chemistry and dyeing in the University of Leeds
and
Arthur Ernest Everest, D.Sc., Ph.D., F.I.C., of the Wilton Research Laboratories; Late head of the Department of Coal-tar Colour Chemistry; Technical College, Huddersfield
Longmans, Green and Co.
39 Paternoster Row, London
Fourth Avenue & 30th Street, New York
Bombay, Calcutta, and Madras
1918

Kaikki kuvat (kemialliset kaavat) puuttuvat // None of the illustrations (of chemical formulas) included.

Anthemis Nobilis. An examination of the flowers of Anthemis nobilis (Linn.) by Power and Browning (Chem. Soc. Trans., 1914, 105, 1833) has shown that these contain in addition to numerous other substances an apigenin glucoside, C21H20O10.2H2O, faintly yellow microscopic crystals melting at 178-180°. It dissolves in alkalis with a yellow colour and gives with aqueous ferric chloride a purplish-brown coloration. Dried at 125-130° it loses one molecule of water of crystallisation, but the second molecule cannot be eliminated without decomposing the substance. This is evident from the composition of the hexa-acetyl derivative, C21H14O10(COCH3)6, colourless microscopic crystals, melting-point 144-146°, the molecule of water in question being eliminated in the process of acetylation.

By digestion with 5 per cent, aqueous sulphuric acid for three hours, this glucoside yields apigenin and dextrose according to the equation -
C21H20O10, H2O = C15H10O5 + C6H12O6

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