Trichothecin is the isocrotonic ester of the ketonic alcohol, trichothecolone. On the basis of its properties and those of degradation products, obtained by oxidation, alkaline fission, and dehydrogenation, the alternative structures (I; R=H) and ( 11), of which the former is preferred, are proposed for trichothecolone. On treatment with hot potassium hydroxide, trichothecolone gives an isomer, isotrichothecolone. Some properties and derivatives of the latter are described.TRICHOTHECIN is an antifungal substance, produced by the fungus Trichothecium roseurn Link.1 Some of its chemical and biological properties have been de~cribed.~-~ It is an ester, Cl,H,O5, giving on hydrolysis isocrotonic acid and a ketonic alcohol, trichothecolone, C,,H,04.Trichothecin was readily hydrogenated at atmospheric pressure with palladiumcharcoal, two mols. of hydrogen being absorbed to give the non-crystalline tetrahydrotrichothecin. This uptake was accounted for by saturation of one ethylenic double bond in the isocrotonic ester group and a second ethylenic double bond in the trichothecolone part of the molecule. Trichothecin contained a reactive carbonyl group, which was retained in tetrahydrotrichothecin. Kuhn-Roth determinations showed that trichothecin has at least three C-methyl groups. No methoxyl group was detected. The infrared spectrum of trichothecin had bands a t 1670 (up-unsaturated ketone), 1710 and 1177 (a@unsaturated ester), and 1650 cm.-l (attributed to ethylenic unsaturation). Absence of a band in the region of 3400 cm.-l indicated absence of hydroxyl groups which was confirmed by indifference of trichothecin, even under the most vigorous conditions, to acetic anhydride or benzoyl chloride. There was no indication of benzenoid absorption in the spectrum.
