Costus lactone

Semmler and Feldstein have isolated a lactone from costus root oil, which they named costus lactone, having the following characters —... 

Dihydro-costus lactone, CjjHj Og, is also present in the oil. 

The same substrate (249) was fed by A. niger for 7 days to afford four metabolites, costus lactone (250), and their derivatives (251-253), of which 251 was the major product (28%) while the same substrate was cultivated with A. niger for 10 days, two minor metabolites (254, 255) were newly obtained in addition to 252 and 253 of which the latter lactone was predominant (20.7%) (Hashimoto et al., 2001) (Figure 20.77). 

Costus essential oil is used in perfumery and has been responsible for a number of cases of contact dermatitis (Cheminat et al. 1981). Sesquiterpene lactone compounds are believed to be responsible for the reaction (Cheminat et al. 1981 Pandey et al. 2007 Robinson et al. 2008 Sun et al. 2003). 

The S. A-E are components of the dried, Chinese Saussurea root (Saussurea costus, syn. 5. lappa) which is used in Chinese and Japanese traditional medicine for stomach complaints. S. A, C20H29NO4, Mr 347.45, mp, 115-117°C, [a]i3 +36.7° (CH3OH), corresponds to the Michael adduct from costunolide and proline S. B and C represent the amino acid conjugates of proline and asparagine, respectively, with the corresponding a, 8-unsaturated dehydrocostus lactone. In animal experiments, S. A exhibits a pronounced protective effect against stress-induced stomach ulcers. 

Costunolide is a germacranolide sesquiterpene lactone extracted from costus oil. With alantolactone and dehydrocostuslactone, it is a component of lactone mix used to elicit reactions in Compositae-sensitive patients. An erythema-multiform-like occupational contact dermatitis case occurred in a chemistry student after accidental exposure to costus oil (CJ Le Coz JP Lepoittevin, unpublished results). 

A guaianolide sesquiterpene lactone extracted from costus oil. Dehydrocostuslactone is one of the components of lactone-mix, with costunolide and alantolac-tone, used to detect Compositae-sensitive patients. 

From the fraction boiling at 200 to 210 at 11 mm. a lactone of the formula was obtained, which the authors have named costus... 

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