Determination of the absolute configuration of carbohydrate components of flavonol glycosides of the chestnut

Conclusions On the basis of the rates of their acid hydrolysis, their optical activities, and their IR spectra, it has been established that the glycosides ofAesculus hippocastanum L. are (SK-1) 3--L-arabofuranosyloxy-5,7,4-trihydroxyflavone, (SK-2) 3--L-rhamnofuranosyloxy-5,7,4-trihydroxyflavone, (SK-3) 3--L-arabofuranosyloxy-5,7,3,4-tetrahydroxyflavone, and (SK-4) 3--L-rhamnofuranosyloxy-5,7,3,4-tetrahydroxyflavone.The glycoside SK-3 is identical with avicularin isolated from the leaves ofPsidium quajava [5]. The complete structures of the other three glycosides have been established for the first time.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 5–7, 1969     

Steroid compounds from ophiuroids II. Sulfated steroids from Ophiura sarsi and Ophiura leptoctenia

The previously described cholest-5-ene-3,4,21-triol 3-(sodium sulfate) has been obtained from extracts of the Far Eastern ophiuroidOphiura leptoctenia. Two new sulfated steroid polyols have been isolated from the ophiuroidO.sarsi; cholest-5-ene-3,4,21-triol 3,21-di(sodium sulfate) and cholest-5-ene-2,3,21-triol tri(sodium sulfate). The new polyol 4-acetoxycholest-5-ene-3,21-diol has been identified among the products of the desulfation of this ophiuroid.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 483–487, July–August, 1990.     

Cardiac glycosides of Cheiranthus allioni. V

Conclusions Two additional cardiac glycosides, glucoerysimoside and glucoerysimosol, have been isolated from the seeds ofCheiranthus allioni Hort. Glucoerysimoside is strophanthidin 3-[O--D-digitoxopyranosyl-(4 1)-O--D-glucopyranosyl-(4 1)--D-glucopyranoside]. Glucoerysimosol is a new cardenolide having the same carbohydrate component, but its aglycone is strophanthidol. From these glycosides a new trisaccharide has been obtained which has been characterized as 4-O--cellobiosyl-D-digitoxose.Khar'kov Scientific-Research Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 566–571, September–October, 1970.     

Electrochemical Determination of 4-Nitrophenol Using a Single-Wall Carbon Nanotube Film-Coated Glassy Carbon Electrode

A single-wall carbon nanotubes (SWNT) film coated glassy carbon electrode (GCE) was fabricated for the direct determination of 4-nitrophenol (4-NP). The electrochemical behaviors of 4-NP at the SWNT-film coated GCE were examined. In 0.1M phosphate buffer with a pH of 5.0, 4-NP yields a very sensitive and well-defined reduction peak at the SWNT-modified GCE. It is found that the SWNT film exhibits obvious electrocatalytic activity towards the reduction of 4-NP since it not only increases the reduction peak current but also lowers the reduction overpotential. Based on this, an electrochemical method was proposed for the direct determination of 4-NP. The reduction peak current varies linearly with the concentration of 4-NP ranging from 1×10^–8 to 5×10^–6M, and the detection limit is 2.5×10^–9M after 3min of open-circuit accumulation. The relative standard deviation at 2×10^–7M 4-NP was about 6% (n=10), suggesting excellent reproducibility. This new method was successfully employed to determine 4-NP in several lake water samples.     

Triterpene glycosides of Astragalus and their genins XXX. Cycloaraloside A from Astragalus amarus

In addition to -sitosterol, cyclosieversigenin, and -sitosterol -D-glucopyranoside, the roots of the plantAstragalus amarus Pall. (Leguminosae) have yielded a new triterpene glycoside of the cycloartane series — cycloaraloside A, which has the structure of 2OR,24S-epoxycycloartane-3,6,16,25-tetraol 3-O--D-glucopyranoside.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 806–809, November–December, 1989.     

Triterpene glycosides of alfalfa. IV. Medicoside J

A new triterpene glycoside has been isolated from the roots ofMedicago sativa L. (family Fabaceae) — medicoside J, and its structure has been established as a medicagenic acid 3-O--D-glucopyranoside 28-O-[O--D-xylopyranosyl-(1 4)-O--L-rhamnopyranosyl-(1 2)--L-arabinopyranoside].Institute of the Chemistry of Plant Substances of the Uzbek Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 610–613, September–December, 1986.     

Flavonoids of Ammothamnus lehmannii. Structure of lehmannin and of ammothamnidin

The new flavanon lehmannin (I) has been isolated from the roots ofAmmothamnus lehmannii Bunge. On the basis of chemical transformations and with the aid of physicochemical characteristics it has been established that compound (I) has the structure of 2,4,7-trihydroxy-8-(2-isopropenyl-5-methylhex-4-enyl)flavanone. The alkaline cleavage of lehmannin gave ammothamnidin (V). The structure proposed previously for the chalcone ammothamnidin has been corrected. It has been shown that it has the structure of 2,2-4,4-tetrahydroxy-3-(2-isopropenyl-5-methylhex-4- enyl)chalcone. A comparative study of the¹³C NMR spectra of a number of flavanones has revealed an empirical law permitting the prediction of the presence or absence of substituents (OH and OCH₃) at C-2 from the value of the chemical shift of the signal of the C-2 carbon atom.Institute of the Chemistry of Plant Substances of the Uzbek SSR Academy of Sciences, Tashkent. I. P. Pavlov Samarkand State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 516–524, July–August, 1987.     

Iriterpene glycosides of Astragalus and their genins XLIII. Cycloaraloside B from Astragalus amarus

The structure of a new cycloartane glycoside, cycloaraloside B, isolated from the roots ofAstragalus amarus Pall. (Leguminosae) has been established on the basis of chemical transformations and spectral characteristics: it is 20R,24S-epoxycycloartane-3,6,16,25-tetraol 3-O-[O--L-rhamnopyranosyl-(12)-(6-O-acetyl--D-glucopyranoside)].Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 528–531, September–October, 1992.     

The structure of seselirin: A new chromone from the roots ofSeseli sessiliflorum

Conclusions From the roots ofSeseli sessiliflorum Schrenk a new chromone has been isolated for which the structure of 2,2-dimethyl-3-(3-methylthioacryloyloxy)-3,4-dihydropyrano-5,6:6,7-(5-hydroxy-2-methyl) chromone has been proposed. It is the first representative of this group of natural compounds containing sulfur.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 4, pp. 412–415, 1970     

Flavonoids of Crataegus. The structure of cratenacin

Conclusions The complete structure of the new C-glycoside, cratenacin, isolated from the leaves ofCrataegus curvisepala (Lindm.) has been determined by chemical and spectral methods; it is 5,7,4-trihydroxyflavone 8-C-[6-O-acetyl--D-glucopyranosyl(4 1)--L-rhamnopyranoside].Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 234–236, 1969     

Investigations in the field of complex lipids

Summary 1. The synthesis of L-(+)--oleoyl--linoleoyl--glycerylphosphorylethanolamine has been effected.2. During the investigations the following substances were isolated and characterized: L--oleoyl--glycerylphosphoryl-N-phthaloylethanolamine and L---linoleoyl--glycerylphosphoryl-N-phthanoylethanolamine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 2, pp. 80–83, 1966     

Depsipeptides Communication 31. Synthesis of depsipeptides containing α-hydroxy α-amino acid residues

Summary Depsipeptides containing -hydroxy -amino acid residues as hydroxy-acid component were synthesized.Communication 11 of the series -Substituted -Amino Acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 1987–1992, November 1965     

Some peculiarities of π—π interactions between tetraphenylporphine metal complexes and aromatic solvents

The — complexes of metal tetraphenylporphinates with benzene, toluene, and xylenes were characterized by means of thermogravimetry. The ability of metalloporphyrins to form — complexes with certain -donor molecules depends largely on the -acceptor capacity of the macroheterocycle, and on the peculiarities of the metal—porphyrin coordinative linkage. Stoichiometry, energy parameters, and thermal stability of the - complexes of metalloporphyrins with various aromatic ligands are determined to a great extent by the molecular structure of solvents.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp.850–853, May, 1993.     

Cardiac glycosides of Erysimum crepidifolium

Summary Four cardiac glycosides have been isolated from the leaves ofErysimum crepidifolium Rchb. Three of them have been identified as erysimin, erysimoside, and erycordin. The fourth glycoside, which has been named glucostrophalloside, is new, and it consists of strophanthidin 3-O-[4-O--D-glucopyranosyl--D-allomethylopyranoside].Khar'kov Scientific-Research Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 611–614, September–October, 1974.     

Triterpene glycosides ofLeontice eversmannii

Summary The structures of the triterpene glycosides leontiside A and leontoside B fromLeontice eversmannii have been established. It has been shown that the leontoside A is hederagenin 3--L-arabopyranoside and leontoside B is hederagenin 3--L-arabopyranosido-4--D-glucopyranoside.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 2, pp. 101–105, 1967     

Reaction of ammonia with β,β′-dithioalkyl-α,α′-divinyl ketones

Conclusions Syntheses are reported for ,-dithioalkyldivinyl ketones, which react with ammonia to give -amino--thioalkyldivinyl ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2414–2415, October, 1988.The authors thank A. M. Kachurin for assistance in taking the spectra.     

Triterpene glycosides of alfalfa. VI. Medicoside L

A new triterpene pentaglycoside — medicoside L — has been isolated from the roots ofMedicago sativa L. (Leguminosae). It has the structure of medicagenic acid 28-O--D-glucopyranoside 3-O-{[O--D-glucopyranosyl-(1 2)][O--L-rhamnopyranosyl-(1 3)]-O--D-glucopyranosyl-(1 2)}--D-glucopyranoside.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–228, March–April, 1990.