Preparative isolation of guaipyridine sesquiterpene alkaloid from Artemisia rupestris L. flowers using high-speed counter-current chromatography

Although the medicinal plant Artemisia rupestris L. has been widely researched for several decades, its alkaloids have never been isolated before. To our surprise, the alkaloids in the plant were not detected in the stems but detected in the flowers. Herein, a novel and strange guaipyridine sesquiterpene alkaloid with a carboxyl group named rupestine was purified successfully from the total alkaloids extracted from the flowers by high-speed counter-current chromatography (HSCCC). The two-phase solvent system used was composed of ethyl acetate-methanol-water (8:1:7, v/v/v). Fifty six milligrams of rupestine was obtained at over 97% purity and 95% recovery from 200 mg of the total alkaloids in one-step separation. Its structure was elucidated by spectroscopic methods including high resolution ESI-MS, (1)H NMR, (13)C NMR, Heteronuclear Multiple Bond Correlation (HMBC), Heteronuclear Single Quantum Coherence (HSQC), and Nuclear Overhauser Enhancement Spectroscopy (NOESY).     

Phytochemical investigation of Datura innoxia

The alkaloids in the various organs of the plantDatura innoxia cultivated in the Darmina sovkhoz [collective farm], Chimkent province, Kazakh SSR, have been studied. Ten individual bases and two terpenoids were isolated. The percentages of the main alkaloids have been determined. It has been shown that the epigeal part of the plant can be used to obtain scopolamine hydrobromide.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Bioorganicheskaya Khimiya, No. 1, pp. 36–38, 1989.     

Derivatives of the alkaloid convolvine and their pharmacological activity

A series of new convolvine derivatives based on the alkaloid from Convolvulus subhirsutus and C. pseudocanthabrica were synthesized using alkylhalides and aliphatic and aromatic acid chlorides. Results of biological tests showed that convolvine and its derivatives exhibited pronounced antihypoxic, immunomodulating, and anti-inflammatory activity.     

Associate of Betonicin with Urea from <Emphasis Type="Italic">Phlomis regelii</Emphasis>

The structure of a base isolated from the aerial part of Phlomis regelii as a solvate of the pyrrolidine alkaloid betonicin with urea in a 1:1 ratio was solved. A three-dimensional framework of intermolecular H-bonds was formed by the betonicin and urea molecules in the crystal. The inclusion of a urea molecule in the complex results in stable heteromolecular associates that persist during isolation of the alkaloid.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 46–48, January–February, 2005.     

The NMR investigation of alkaloids. IX.13C NMR spectra and stereochemistry of convolvine,convolamine, convoline,convolidine, subhirsine,and 6-hydroxyhyoscyamine

On the basis of the results of a study of the¹³C NMR spectra, a correlation has been made of the CSs of the¹³C carbon nuclei with the structure and stereochemistry of the tropane alkaloids convolvine, convolamine, convoline, convolidine, subhirsine, and 6-hydroxyhyoscyamine. It has been established that the N-CH₃ group in convolamine and the N-OH group in convoline are oriented equatorially, and the N-CH₃ in hydroxyhyoscyamine axially.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 80–84, January–February, 1986.     

Alkaloids. Plants,structures, properties

For the beginning of the review, see Chemistry of Natural Compounds, No. 1, 102; No. 2, 216 (1996)