Oxytropis alkaloids II. Structure of oxytriphine

The new alkaloid oxytriphine, the parent of natural 2-oxazoline derivatives, has been isolated from the epigeal part ofOxytropis trichophysa; and its structure has been established as (5S)-(+)-2,5-diphenyl-2-oxazoline. (-)-N-Benzoyl-2-phenyl-2-hydroxyethylamine and benzoic acid have been detected in this plant for the first time. A hypothesis of the possible biogenetic interrelationship of the compounds isolated is put forward.     

Theoretical Study of Molecular Structure, Tautomerism, and Geometrical Isomerism of N-Methyl- and N-Phenyl-Substituted Cyclic Imidazolines, Oxazolines, and Thiazolines

The geometries of various tautomers and isomers of 2-methylamino-2-imidazoline, 2-methylamino-2-oxazoline, 2-methylamino-2-thiazoline, 2-phenylamino-2-imidazoline, 2-phenylamino-2-oxazoline, and 2-phenylamino-2-thiazoline have been studied using the Becke3LYP/6–31+G(d,p) DFT, ONIOM(Becke3LYP/6–31+G(d,p):HF/3–21G^*) and ONIOM(Becke3LYP/6–31+G(d,p):AM1) methods. The optimized geometries indicate that these molecules show a distinctly nonplanar configuration of the cyclic moieties. In the gas phase, the amino tautomers (with exception of 2-phenylamino-2-imidazoline) are computed to be more stable than the imino tautomers. Of the two possible (E and Z) isomers of methyl and phenyl derivatives of imino-oxazolidine and imino-thiazolidine species, the (Z) isomers have the lowest energy. The iminozation free energies in the gas phase were found to be 5 – 15 kJ/mol. Absolute values of K _T depend strongly on the accuracy of the method used for calculation of free energy. Solvation (using the MD simulations) causes, in most cases, a shift in tautomeric preference toward the imino species.     

Isolation of an indanone fromEquisetum arvense and its crystal and molecular structure

Summary From the herbEquisetum arvense L. an indanone compound has been isolated for the first time for which the structure of 4-hydroxy-6-(2-hydroxyethyl)-2,2,5,7-tetramethylindanone has been established by spectroscopy and x-ray structural analysis.Irkutsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR. Institute of Applied Chemistry, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 508–513, July–August, 1978.     

Tannins ofGeranium sanguineum

A study has been made of the phenolic compounds ofGeranium sanguineum. One tannin of the hydrolyzable series has been isolated from the epigeal part, and for this the structure of 1,3-bis-O-digalloyl-2-O-galloyl-4,6-(hexahydroxydiphenoyl)--D-glucose is proposed. Three new proanthocyanidins have been isolated from the roots, and most probable structures have been put forward for these.Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 238–246, March–April, 1997.     

Rhapisterone D 20-acetate from the seeds ofLeuzea carthamoides

In addition to makisterone A, the new ecdysteroid rhapisterone D 20-acetate has been isolated from the seeds ofLeuzea carthamoides.Institute of Petrochemistry and Catalysis, Academy of Sciences of the Bashkortostan Republic, and Urals Scientific Center, Russian Academy of Sciences, 450075, Ufa, Prospekt Oktyabrya, 141, fax (3472) 31-27-50. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 207–208, March–April, 1999.     

A new terpene ketone, a component of the essential oil ofElsholtzia ciliata

A new terpene ketone which has been called dehydroelsholtsia ketone has been isolated from the essential oil ofElsholtzia ciliata (Thumb.) Hyl. The structure of dehydroelsholtzia ketone as 3-methyl-2-(3-methylbut-2-enoyl)furan has been proposed on the basis of a study of its IR, PMR, mass and¹³C spectra and has been confirmed by its conversion into elsholtzia ketone.Institute of Chemical Sciences, Academy of Sciences of the Republic of Kazakhstan, Alma-Ata. Siberian State Medical Institute, Tomsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 823–824, November–December, 1993.     

Diterpenoids ofPulicaria salviifolia. III. The structure of salvicinin

The new diterpene acid salvicinin has been isolated from the epigeal part ofPulicaria salviifolia and its structure has been established as 15-acetoxy-6-hydroxy-trans-cleroda-3,13-dien-19-oic acid. A capacity of salvicinin for undergoing lactonization in the presence of acetic anhydride has been revealed, and the lactone formed has been isolated and chracterized.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Fax (3712) 62 73 48. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 246–249, March–April, 1994.     

Low surface energy polymers and surface active block polymers. I. t-butylphenyl containing polymers

Two new monomers in the 2-oxazoline series were synthesized and polymerized. These were 2-[4-(t-butyl)phenyl]-2-oxazoline ( I ) and 2-[(3-(3,5-di-t-butyl)phenoxy)propyl]-2-oxazoline ( II ). The polymer from I crystallized readily during bulk polymerization and showed T_m at 592 K (319°C). After annealing, the polymer showed a critical surface tension of 23.2 dyn/cm. Polymer from II was amorphous; hence, annealing showed little effect on contact angles. Block polymers were made with I (Xn = 10) and ethyl oxazoline (Xn = 6,20,60). Very sharp molecular weight distributions were obtained. All samples crystallized when annealed. The block polymer was an effective emulsifier for emulsion polymerization of butyl acrylate at 0.1%.     

Berberis Alkaloids XXXVIII. Turcamine — A new isoquinoline alkaloid fromBerberis turcomanica

The new isoquinoline alkaloid turcamine (1) has been isolated from the leaves ofBerberis turcomanica, and its structure has been established as 8-hydroxy-7-methoxy-2-methyltetrahydroisoquinoline. A relationship has been found between a substituent at C-8 and the multiplicities of the signals from C-5 and C-6.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 894–896, November–December, 1996. Original article submitted April 15, 1996.     

3-Oxocostusic acid fromArtemisia altaiensis

From the epigeal part ofArtemisia altaiensis Krash. we have isolated 3-oxocostus acid (selina-4,11(13)-dien-3-on-12-oic acid), the structure of the molecule of which has been confirmed by x-ray structural analysis, while its absolute configuration has been established from the results of circular dichroism.Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 181–184, March–April, 1998.     

Temperature-dependent interfacial properties of hydrophobically end-modified poly(2-isopropyl-2-oxazoline)s assemblies at the air/water interface and on solid substrates

We describe herein the properties at the air/water (A/W) interface of hydrophobically end-modified (HM) poly(2-isopropyl-2-oxazoline)s (PiPrOx) bearing an n-octadecyl chain on both termini (telechelic HM-PiPrOx) or on one chain end (semitelechelic HM-PiPrOx) for different subphase temperatures and spreading solvents using the Langmuir film balance technique. The polymer interfacial properties revealed by the π–A isotherms depend markedly on the architecture and molecular weight of the polymer. On cold water subphases (14 °C), diffusion of PiPrOx chains onto water takes place for all polymers in the intermediate compressibility region (5 mN m⁻¹). At higher subphase temperatures (36 and 48 °C), the HM-PiPrOx film exhibited remarkable stability with time. Brewster angle microscopy (BAM) imaging of the A/W interface showed that the polymer assembly was not uniform and that large domains formed, either isolated grains or pearl necklaces, depending on the polymer structure, the concentration of the spreading solution and the subphase temperature. The Langmuir films were transferred onto hydrophilic substrates (silica) by the Langmuir–Blodgett (LB) technique and onto hydrophobic substrates (gold) by Langmuir–Schaefer (LS) film deposition, resulting in the formation of adsorbed particles ranging in size from 200 to 500 nm, depending on the polymer architecture and the substrate temperature. The particles presented “Janus”-like hydrophilic/hydrophobic characteristics.     

Synthesis of novel glycopeptide-polyoxazoline block copolymers by direct coupling between living anionic and cationic polymerization systems

A novel glycopeptide-containing block copolymer, poly[O-(tetra-O-acetyl-β-D -glucopyranosyl)-L -serine]-block-poly(2-methyl-2-oxazoline) ( 5 ), was synthesized by mutual termination of living polymerizations of a sugar-substituted α-amino acid N-carboxyanhydride (NCA) ( 1 ) and 2-methyl-2-oxazoline ( 3 ). 5 was deacetylated to provide the glycopeptide-polyoxazoline block copolymer, poly[O-(β-D -glucopyranosyl)-L -serine]-block-poly(2-methyl-2-oxazoline) ( 6 ).     

New alkaloids ofDipthychocarpus strictus

New alkaloids with mp 57–59°C and diptamine have been isolated from the seeds and epigeal part ofDipthychocarpus strictus collected in Chimkent Province (KazSSR). It has been established that the base with mp 57–59°C has the structure of N,N-di(6-methylthiohexyl)urea, while diptamine is N-isopropyl-N-(7-methylsulfonylheptyl)urea.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedeninii, No. 3, pp. 363–365, May–June, 1980.     

The structure of xeroferin

Summary From the roots ofFerula xeromorpha Eug. Kor. (xeromorphic giantfennel) an ester of undescribed alcohol — himachal-2-ene-4,7-diol — and isovanillic acid has been isolated.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 581–584, September–October, 1978.     

Berberis alkaloids XXXV. The structure of nummularine

The new N-benzyltetrahydroisoquinoline alkaloid nummularine has been isolated from the leaves ofBerberis nummularia. On the basis of a study of its spectral characteristics (PMR, IR, and mass spectra), the structure of nummularine has been established as 6-hydroxy-N-(3-hydroxy-4-methoxybenzyl)-7-methoxy-1-methyltetrahydroisoquinoline.Translated from Khimiya Prirodnykh Soedinenii, Vol. 33, No. 1, pp. 91–93, January–February, 1997.     

Structure of diptocarpilidine

Diptocarpilidine (bp 193–194° (4 mm)) has been isolated from the epigeal part and seeds ofDiptychocarpus strictus (Fisch) Trautv., and its structure has been established as 1-cyano-6-methylsulfinylhexane.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 84–86, January–February, 1984.     

Cardenolides ofCoronilla glauca andC. scorpioides

The cardenolide glycosides glucocorotoxigenin, scorpioside, and coronillobioside and a new compound which has been called glucocoroglaucigenin have been isolated from the seeds ofCoronilla glauca L. for the first time. The new glycoside has the structure of 3-(-D-glucopyranosyloxy)-14,19-dihydroxy-5-card-20(22)-enolide. This glycoside has also been isolated from the seeds ofC. scorpioides.Khar'kov Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 676–679, September–October, 1985.     

Ab initio studies of peroxynitrite anion-water complexes

Quantum mechanical methods have been applied to thecis-ONOO^–-H₂O,cis-ONOO^–-(H₂O)₂ andtrans- ONOO^–-H₂O complexes. Equilibrium geometries, binding energies, net atomic charges and vibrational frequencies are presented for several different arrangements. The MØller-Plessett second-order perturbation (MP2) method predicted shorter hydrogen bonds than the SCF method, but the computed Hartree-Fock (HF) binding energies are similar to counterpoise corrected MP2 values. The geometry changes of ONOO^– and water after solvation are examined. The ONOO^– and H₂O bond length changes follow typical hydrogen bond structural trends, whereas bond angles in ONOO^– are unaffected when the hydrogen bond is formed, similar to the conclusions from NO ₂ ^– -(H₂O) _n HF/6-31G studies and Monte Carlo simulations. Thecis-ONOO^–-(H₂O) _n frequencies are compared with the solution Raman spectrum and with calculations on isolated ONOO^–.     

Polysaccharide from the leaves ofPhytolacca americana

A polysaccharide has been isolated from the leaves ofPhytolacca americana and has been characterized. It has been established that it contains residues of galactose, arabinose, xylose, and rhamnose, in a ratio of 3:4:1:3 and also D-galacturonic acid (85–90%). The results obtained permit the polysaccharide to be assigned to the class of pectin substances.All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 166–169, March–April, 1982.