This section is from the book "The Volatile Oils Vol2", by E. Gildemeister. Also available from Amazon: The Volatile Oils.
The flowers of Trifolium incarnatum, L. have been distilled by H. Rogerson4) who obtained 0,029 p.c. of a pale yellow oil with reference to the dried clover and 0,006 p.c. with reference to the fresh flowers. The oil, which has a strong odor boiled between 120 and 180° (15 mm.); d20/20o0,9597; aD - 1°48 Furfurol was the only constituent that could be identified.
From the flowers of the red clover, Trifolium pratense, L., F. B. Power and A. H. Salway5) obtained an oil with a rather unpleasant odor. Computed with reference to the dry flowers the yield was 0,028 p. c, with reference to the fresh flowers 0,006 p.c. d20/20o0,9476; aD + 4°10'. Furfurol was identified.
1) Apotheker Ztg. 25 (1910), 303.
2) Ibidem 18 (1903), 51.
3) H. Haensel, Ibidem 15 (1900), 516.
4) Journ. chem. Soc. 97 (1910), 1004.
5) Ibidem 232.
 
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