Helenium autumnale

This American genus has yielded several ornamental plants (e.g., Helenium autumnale), but is also known for its toxic effects on herbivores. Helenium genus comprises about 40 species of annual and perennial herbs. Helenium mexicanum is taken orally if a person is very sick or to treat a stomachache, faint heartbeat, throbbing temples, quivering nerves, fever, or pus in the genital organ. Helenium quadridentatum is used for treatment of fever, catarrh, and testicular inflammations and as a diuretic and insecticide. 

The structure of autumnolide (443), an anticancer agent isolated from Helenium autumnale, has been determined by X-ray analysis.Autumnolide co-occurs with the antineoplastic agent helenalin (440), and although the compounds have very similar structures their conformations in the solid state are different. Thus only in autumnolide does the preferred conformation permit hydrogen-bonding between the C-4 and C-6 hydroxy-groups. Carbon-13 n.m.r. spectra of tenulin (444) and derivatives indicate that the natural compound actually occurs as a mixture of C-16 epimers. ... 

Helenium Autumnale is a tall long-flowering perennial whose blooms appear in late summer to early autumn in cooler cli-... 

Ci5H g04, Mr 262.31, cryst., mp, 168 °C, [ajp -102° (acetone), soluble in alcohol, chloroform, poorly soluble in water. A toxic sesquiterpene lactone that induces sneezing from Helenium and Arnica species such as, e.g., Helenium autumnale and Arnica mon-tana [LD50 (mouse p.o.) 150 mg/kg]. After intoxication, the symptoms are nasal irritation, vomiting, diarrhea, vertigo, palpitation, respiratory impairment, and finally collapse with a weak, very rapid pulse. In the past deaths have been reported after consumption of Arnica preparations. Contact with the skin leads to dermatitis. 

Pigment of Helenium autumnale, Tagetes. Dipalmitate of lutein. Deep red ne les from EtOH. M.p. 92°. Absorption bands in GS , 511, 478, 466 mp. Hyd.—> lutein + paboitic acid. 

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