The structure of anhydrolupinine

Summary It has been shown that the anhydrolupinine obtained from lupinine by the action of water-abstracting agents is a mixture of two isomers differing by the position of a double bond in the ring system of the molecule.V. I. Lenin Tashkent State University. Division of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, TAshkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 495–497, July–August, 1976.     

The structure of vincarine

Summary A new base, vincarine, has been isolated from the roots and epigeal part ofV. erecta. Its formula is C₂₁H₂₄O₃N₂.The structure of vincarine has been established by analysis of the UV, IR, NMR, and mass spectra and also by its conversion into polyneuridine; it is a diastereoisomer of quebrachidine.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 2, pp. 110–113, 1965.     

The structure of luteidine

Summary On the basis of UV,¹³C NMR, and mass spectra, it has been established that luteidine belongs to the group of homoproaporphine alkaloids.The IR, PMR, and¹³C NMR spectra of luteidine and the products of its transformations have permitted the structure of 1-hydroxy-2,13-dimethoxy-11-oxo-9,10-dihydrohomoproaporphine to be proposed for this base.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 354–359, May–June, 1976.     

The structure of zapotin

Spectroscopic evidence is presented which indicates that zapotin, a flavone occurring in seeds of Casimiroa edulis Llave et Lex, is 2′,5,6,6′-tetramethoxyflavone. Zapotin thus has a unique 2′,6′-dimethoxy B-ring which has not previously been reported among naturally occurring flavonoids.     

The structure of karakolidine

Summary As the result of a study of chemical transformations and spectral characteristics, for the new alkaloid karakolidine a lycoctonine skeleton with N-ethyl and C₄-methyl groups, hydroxy groups at C₁ (), C₈, C₁₀ (), and C₁₃, and a methoxy group at C₁₅ () has been established.Some peculiarities of the fragmentation of derivatives of karakoline and karakolidine under the action of electron impact have been found.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 481–486, July–August, 1975.     

The structure of karatavicinol

Conclusions The neutral fraction of the resin of the roots ofFerula karatavica Rgl. et Schmalh. has yielded a new coumarin with the composition C₂₄H₃₂O₅, mp 52–53° C, [] _D ²⁰ -12° (c 7.5; ethanol) which has been called karatavicinol. It has been established that karatavicinol is an ether of umbelliferone and a sesquiterpene aliphatic triol. The structural formula I has been proposed for karatavicinol.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 225–227, 1969     

The structure of octachloropentafulvalene

The structure of octachloropentafulvalene has been redetermined by a 3-dimensional X-ray crystallographic analysis. The space group is monoclinic, C2/c, and cell parameters are a = 14·998, b= 7·9110, c= 11·8068 Å, β= 103·38°. The X-ray intensity data were measured on a computer-controlled diffractometer using Mo radiation. The least-squares structure refinement used anisotropic temperature factors for C and Cl and gave a final R of 0·036. Corrections were applied for absorption, Cl dispersion and secondary isotropic extinction. The central CC is twisted by 37° as a result of Cl?Cl repulsions from one C₅Cl₄ half to the other. The central CC length, 1·365 Å, is only slightly larger than the standard 1·34 Å ethylenic value. The bond distance increase can be explained in terms of a decrease in π-bond character accompanying the CC twist. Carbon-carbon distances in the 5-ring have typical values for the cyclopentadienylidene moiety; there is no evidence for single-double bond delocalization.