7965. Pyrethrosin

Nomenclature

CAS number: 28272-18-6
(1aR,4E,6R,6aR,9aS,10aR)-6-(Acetyloxy)-1a,3,6,6a,7,9a,10,10a-octahydro-4,10a-dimethyl-7-methyleneoxireno[8,9]cyclodeca[1,2-b]furan-8(2H)-one; 1,10-epoxy-6,8-dihydroxygermacra-4,11(13)-dien-12-oic acid 12,8-lactone acetate.
C17H22O5; mol wt 306.35.
C 66.65%, H 7.24%, O 26.11%.

Description and references

From flowers of Chrysanthemum cinerariaefolium Vis., Compositae. Isoln: Thoms, Pharm. Ztg. 1891, 503. Structure: Barton, de Mayo, J. Chem. Soc. 1957, 150; Barton et al., ibid. 1960, 2263. Revised structure: S. Iriuchijima, S. Tamura, Agric. Biol. Chem. 34, 204 (1970); E. J. Gabe et al., Chem. Commun. 1971, 559.

Chemical structure

Properties

Crystals from ethanol, ethyl acetate or benzene + light petroleum, mp 198-200°. [α]D -31° (c = 1.73 in chloroform). uv max: 204, 210, 220, 230 nm (ε 14,600; 12,200; 6000; 1700). Practically insol in water. Sol in hot alcohol, chloroform; slightly sol in ether or petr ether.