Phytoecdysones ofSilene praemixta. I. Silenosterone

In addition to known ecdysteroids (2-deoxy--ecdysone and 2-deoxyecdysterone) fromSilene praemixta (Caryophyllaceae) we have isolated new ones — premixisterone and selenosterone (I), C₂₇H₄₂O₇, mp 115–117°C (from MeOH), [] _D ²⁸ +86.9 ± 2° (c 0.92, MeOH), yield 0.003%. The acetylation of (I) with (CH₃CO)₂O in Py gave 22-acetyl-selenosterone (II), C₂₉H₄₄O₆, mp 210–212°C (MeOH-C₆H₁₄), [] _D ²⁷ +45.5 ± 3° (c 0.16; MeOH). On the basis of physiocochemical and spectral characteristics it has been established that (I) has the structure of 14,22R,25-trihydroxy-5-cholest-7-ene-3,6-dione. The IR, PMR, and mass spectra of (I) and (II) are presented.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 793–797, November–December, 1979.     

Inverse boundary-value problems of cauchy type for harmonic functions

We apply two methods for solving the inverse boundary-value problem (the so-called problem (A)) in the Cauchy statement for an analytic function and an unknown curve ??. We obtain criteria for ?? to be the unit circle. We apply the proposed methods for solving a modified Hadamard example and generalize the obtained results for the case of doubly connected domains.     

Triterpene glycosides ofLeontice eversmannii. I

Summary Triterpene glycosides, which we have called leontosides A, B, C, D, and E, have been isolated from the tubers ofLeontice eversmannii Bge. The monosaccharide composition and the approximate quantitative ratio of the sugars in the carbohydrate moiety of each leontoside have been established. In leontosides A, B, and C, the carbohydrate moiety is bound only to the alcoholic group of hederagenin, while in leontosides D and E there is also an O-acyl glycosidic bond to the carboxy group.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 421–426, 1966     

Triterpene glycosides ofGypsophilla trichotoma

Chemistry of Natural Compounds - The plantGypsophilla trichotoma Wend. has been found to contain four triterpene glycosides, which have been called “trichosides” A, B, C, and D....