Epoxidation of sesquiterpene lactones tourneforin and ludartin

Epoxy derivatives of the sesquiterpene lactones ludartin and tourneforin were synthesized. Their structures were elucidated using spectral data and x-ray structure analysis.     

Thermochemical Characteristics of a Series of Terpenoids,Alkaloids, and Flavonoids

The heats of combustion and melting of a series of natural terpenoids, alkaloids, and flavonoids were estimated by approximate thermochemical methods. From these quantities, the standard heats of formation of the compounds in the liquid (molten) and solid states were calculated.     

Synthesis and steric structure of [2-(3-pyridyl)piperidino](2-vinyloxyethylamino)methanethione

Thioureas derivatives were synthesized on the basis of anabasine, piperidine, and morpholine, and 2-vinyloxyethyl isothiocyanate. X-Ray diffraction was used to determine the steric structure of [2-(3-pyridyl)piperidino](2-vinyloxyethylamino)methanethione.     

Structure of dimethylaminodihydroarglabin hydrochloride

The structure of dimethylaminodihydroarglabin hydrochloride has been determined on the basis of the results of an x-ray structural investigation.Institute of Phytochemistry, Ministry of Science and Higher Education, Republic of Kazakhstan, 470032, Karaganda, Ul. Erzhanova, a/ya 19, fax 433773 E-mail: arglabin@phyto.karaganda.su. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 339–341, May–June, 1999.     

Buddledin C from Pulicaria prostrata and selective synthesis of its epoxy derivative

The structure of the sesquiterpene ketone buddledin C isolated from Pulicaria prostrata (Gilib.) Aschers., was confirmed by XSA. The stereochemistry of its epoxide, which was formed selectively by treating it with hydrogen peroxide in alkaline solution, was proposed based on quantum-chemical and molecular-mechanical calculations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 34–37, January–February, 2006.     

Crystal and molecular structure of tigogenin

Tigogenin [(25R)-5α-spirostan-3β-o1] was isolated from Digitalis lanata Ehrh., and its crystal and molecular structure was determined by single crystal X-ray diffraction.