Proanthocyanidins ofZiziphus jujuba

The catechin and proanthocyanidin compositions of the leaves and bark ofZiziphus jujuba have been studied over the vegetation periods. This has led to the isolation of 16 compounds, including 8 monomeric catechins — (–)-epiafzelechin, (–)-epicatechin, (–)-epigallocatechin, (–)-epicatechin gallate, (–)-epigal-locatechin gallate, (+)-catechin, (+)-catechin gallate, and (+)-gallocatechin; 4 dimeric proanthocyanidins — (–)-epiafzelechin-(4-8)-(–)-epicatechin, proanthocyanidin B-2, (–)-epicatechin-(4-8)-(–)-epigallocatechin, and (–)-epiafzelechin-(4-8)-(–)-epigallocatechin; and 4 oligomeric proanthocyanidins consisting of epiafzelechin, epigallocatechin, catechin, and epicatechin with different degrees of polymerization. Their structures have been established by a study of PMR and¹³C NMR spectra and the products of chemical transformation.The materials of this paper were presented at the Second International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–231, March–April, 1997.     

Study of the catechins and proanthocyanidins ofQuercus robur

More than 20 compounds have been isolated from the bark ofQuercus robur. Monomers: (–)-epicatechin, (–)-epicatechin gallate, (+)-catechin, (+)-catechin gallate, (+)-gallocatechin, (–)-epigallocatechin, and (–)-epigallocatechin gallate; dimeric proanthocyanidins: (+)-catechin-(4-8)-(+)-catechin, 3-O-galloyl-(+)-catechin-(4-8)-3-O-galloyl-(+)-catechin, 3-O-galloyl-(+)-gallocatechin-(4-8)-(+)-gallocatechin, (–)-epicatechin-(4-8)-3-O-galloyl-(–)-epigallocatechin gallate, 3-O-galloyl-(–)-epicatechin-(4-8)-3-O-galloyl-(–)-epigallocatechin, 3-O-galloyl-(–)-epigallocatechin-(4-8)-(+)-catechin; and oligomeric proanthocyanidins: D14-D19.Materials presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October, 22–24, 1996).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 819–833, November–December, 1997.     

Proanthocyanidins ofPolygonum coriarium. IV. Structures of proanthocyanidins T3 and T4

Two oligomeric proanthocyanidins have been isolated from the roots ofPolygonum coriarium. By a study of their physical properties and spectral characteristics and analysis of the results of chemical transformations, the chemical structures of these compounds have been established as: (–)-epicatechin-77[O--D-glucopyranosyl]₃ O-⊃-D-glucopyranosyl (m-trigallolyl)-[(4-6)-(–)-epigallocatechin]₂-(4-6)-(–)-epigallocatechin—T3; and (–)-epicatechin-3-O-galloyl-7-[O--D-glucopyranosyl]₃O--D-glucopyranosyl galloyl-[(4-6)-(–)-epicatechin]₄-(4-6)-(–)-epigallocatechin — T4.The materials of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC), Eskiehir, Turkey, October 22–24, 1966).Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 707–713, September–October, 1997.     

Proanthocyanidins ofPolygonum coriarium III. Structures of proanthocyanidins T1 and T2

The roots ofPolygonum coriarum have yielded two oligomeric proanthocyanidins, T1 and T2, and their structures have been established: 3-O-galloyl-7-O-[O-(6-O-galloyl)--D-glucopyranosyl]-(–)-epigallocatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epicatechin-(4-8)-(–)-epigallocatechin 3-O-gallate (T1) and (–)-epicatechin-(4-8)-[3-O-galloyl-(–)-epigallocatechin]-(4-8)-(–)-epicatechin-(4-8)-(+)-catechin (T2).The material of this paper were presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskisehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 588–593, July–August, 1977.     

Oligomeric proanthocyanidin glycosides ofClementsia semenovii. II

The structures of proanthocyanidins CS-3 and CS-4, isolated from the roots ofClementsia semenovii have been established on the basis of chemical and spectral studies. CS-3 is 7-O-(6-O-galloyl--D-Glcp O--D-Glcp O--D-Glcp O--D-Glcp O--D-Glcp)-(+)-catechin-(4—8)-(–)-epigallocatechin-(4—8)-(+)-catechin-(4—8)-(–)-epigaLLocatechin-(4—8)-(–)-epigallocatechin-(4—8)-(–)-epigallocatechin, and CS-4 is 3-O-galloyl-7-O-[6-O-galloyl--D-Glcp O--D-Glcp O--D-Glcp-(+)-gallocatechin-(4—8)-[(+)-catechin-(4—8)-(3-O-galloyl-(–)-epigallocatechin]₂-(4—8)-(–)-epicatechin.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–58, January–February, 1999.     

Phenolic compounds of the plantGossypium hirsutum and of callus tissue from its anthers

The chemical composition of the catechins, leucoanthocyans, proanthocyanidins, and anthocyans of callus tissue ofGossypium hirsutum L. has been studied in comparison with cotton plants growing under natural conditions. From callus tissue of lines L-29, L-32, and L-35 we have isolated (+)-catechin, (±)-gallocatechin, (–)-epicatechin, cyanidin 3-O--D-glucopyranoside, and cyanidin 3-O-[O--D-xylopyranosyl-(14)--D-glucopyranoside]. It has been shown that the components of the phenolic complexes in the plant and in callus tissue differ qualitatively and quantitatively.A. S. Sadykov Institute of Biorganic Chemistry, Academy of Sciences, Tashkent, fax 62 70 71. Institute of Genetics of the Republic of Uzbekistan, Tashkent, fax (3712) 64 32 30. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 250–253, March–April, 1997.     

Examination of the flow behaviour of HEC and hmHEC solutions using structure–property relationships and rheo-optical methods

The effect of solely intermolecular interactions due to hydrophobic alkyl substituents on the flow behaviour of hmHEC solutions was determined via comparison of the structure–property relationships of hmHECs and HECs based on the overlap parameter c[]. For this purpose the ₀–[]–c relationship for HEC was determined to be ₀=8.91·10^–4+8.91·10^–4·c[]+1.07·10^–3(c[])²+1.83·10^–7(c[])^5.56. In addition the structure–property relationship for the longest relaxation time via the –[]–c relationship ·c^1+1/a=2.65·10^–8(c[])²+4.25·10^–8(c[])³+5.44·10^–12(c[])^5.27 has been determined. Although the hmHECs had a higher zero shear viscosity than HECs of comparable overlap parameters at a range of 1<c[]<13, the flow curves could be described via the same –[]–c relationship in that range, indicating a timescale of the intermolecular interactions below the longest relaxation time.The behaviour of the supramolecular structures in solution with an applied shear field was characterized by rheo-optical analysis of the shear thickening behaviour which occurs with addition of surfactant. Contrary to expectations, a slope >1 of the flow birefringence n as a function of shear rate could be observed in double logarithmic plotting. The degree of orientation of the flow birefringence primarily decreases with increasing shear rate, but increases later on at a characteristic shear rate. These two exceptional phenomena can be explained by a pronounced anisotropy of the polymer coils caused by the dilatant flow.This assumption is backed up by the occurrence of a maximum in the dichroism curves which is caused by a finite stability of the aggregated structures in solution. On a molecular basis, these observations agree with the theoretically predicted (Witten and Cohen) transition from intra- to intermolecular polymer micelles. The detected aggregates correspond with the polymer chains that are aligned in one micelle.Abbreviations a Exponent of the Mark–Houwink relationship - c_[]* Critical concentration (determined by intrinsic viscosity) - c_LS* Critical concentration (determined by light scattering) - HASE Hydrophobically modified alkali-swellable emulsions - HEUR Hydrophobically modified ethoxylated urethanes - hmHEC Hydrophobically modified hydroxyethylcellulose - HEC Hydroxyethylcellulose - HPMC Hydroxypropylmethylcellulose - M Molecular mass - MS Molar degree of substitution - n Slope of the flow curve - SEC Size exclusion chromatography - R_G Radius of gyration - Viscosity - ₀ Zero-shear viscosity - _sp Specific viscosity - Longest relaxation time - n Birefringence - n_i Intrinsic birefringence - n_f Form birefringence - n Dichroism - Orientation of the birefringence - ̇ Shear rate     

Triterpene glycosides of Astragalus and of their genins. X. Cyclogalegigenin from Astragalus galegiformis

The flowers of the plantAstragalus galegiformis L. have yielded a new isoprenoid — cyclogalegigenin — the structure of which has been established on the basis of chemical transformations and spectral characteristics as 20R,24S-epoxycycloartane-3,6,16,25-tetraol.I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 332–339, May–June, 1983.     

Proanthocyanidins of Polygonum coriarium. I

Six proanthocyanidins have been isolated from the roots ofPolygonium coriarium. The structures of three oligomeric proanthocyanidins have been established: taranin, consisting of [epigallocatechin gallate]-(48)-[epigallocatechin gallate]-(48)-[epigallocatechin-(48)-epigallocatechin₂-(48)-epigallocatechin; taranoside A - [epigallocatechin gallate]-7-0-[-(16)--D-Glcp]₃-(48)-[epigallocatechin-(48)-epigallocatechin]₂-(48)-gallocatechin; and taranoside B - [epigallocatechin gallate]-7-O-[-(16)--D-Glcp]₄-(48)-[epigallocatechin-(48)-epigallocatechin]₂-(48)-epigallocatechin-(48)-[epigallocatechin gallate).Institute of the Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 59–67, January–February, 1992     

Top soil environmental radioactivity in Akwa Ibom State of Nigeria

A survey of top soil environmental radioactivity in Akwa Ibom State of Nigeria has bean investigated. The results vary considerably from one environment to another ranging between a minimum of 161 mBq·g^–1 and a maximum value of 648 mBq·g^–1 -activity. The work reveals that hospitals and health centres lead in top soil radioactivity with the highest mean values of (378 mBq·g^–1) and (294 mBq·g^–1) followed closely by industrial areas with mean values of (372 mBq·g^–1) and (283 mBq· g^–1) trailing beaches and recreation centres having average values of (364 mBq·g^–1) and (273 mBq·g^–1). Lower levels of top soil radioactivity were observed mostly in environments with high level human interaction activity such as schools, offices, environments and recreation centres. An overall top soil mean of 342 mBq·g^–1 -activity, 271 mBq·g^–1 -activity and 71 mBq·g^–1 -activity were observed in the State.     

Synthesis and thermal decomposition of 3-aroyl-4-aryl-2-pyrazolines

Summary 3-Aroyl-4-aryl-2-pyrazolines (21–40) have been synthesized by the reaction of ,-unsaturated ketones (1–20) with diazomethane. These 2-pyrazolines gave -methyl-,-unsaturated ketones (41–46) on thermal denitrogenation.Dedicated to Prof. Dr.F. Sauter on the occasion of his 65^th birthday     

Asymmetric Solid–Gas Hydrohalogenation of Unfunctionalized Olefins via Formation of Crystalline Cyclodextrin Complexes

Asymmetric solid–gas hydrohalogenation of styrene, -methylstyrene,allylbenzene, and 2-norbornene as unfunctionalized olefins was carried out by using theirchiral crystalline - and -cyclodextrin complexes by exposing them to gaseous HCl and HBrin the dark at room temperature. The optical purities of the Markovnikov products obtainedfrom the ionic addition of HCl to the included olefins appear considerably higher than thosefrom the reaction with HBr. The highest enantioselectivities of 58% and 62% enantiomericexcess (ee) were obtained for the hydrochlorination of 3-phenyl-1-propene (allylbenzene) inthe crystalline - and -cyclodextrin complexes, respectively, and both reactions, which hadlittle danger of racemization, gave (S)-(+)-2-chloro-1-phenylpropane as the same predominantproduct in moderate chemical yields. A much lower enantioselectivity (<10% ee) wasobserved in the hydrobromination of the same olefin in the solid - and -cyclodextrincomplexes involving a racemization reaction. The enantiofacial selection provided the (S)-enantiomer similarly during hydrochlorination.     

Oligomeric proanthocyanidin glycosides ofRhodiola pamiroalaica. II

In a continuation of investigations of proanthocyanidins of the roots ofRhodiola pamiroalaica, we have isolated proanthocyanidins RP-3 and RP-4. Their compositions, structures, and relative configurations have been investigated: RP-3 is 7-O-(6-O-galloyl--D-Glcp)-3-O-galloyl-(-)-epigallocatechin-(4-8)-[(-)-epicatechin-(4-8)-(3-O-galloyl-(-)-epigallocatechin)]₂-(4-8)-[5-O-(-D-GlcpO--D-Glcp)-(+)-catechin], and RP-4 is 7-O-(6-O-galloyl--D-Glcp-3-O-galloyl-(-)-epigallocatechin-(4-8)-[3-O-galloyl-(-)-galloyl-5-(-D-GlcpO--D-Glcp)-(-)-epigallocatechinTranslated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 42–49, January–February, 1999.     

Cardenolides of the seeds ofCoronilla glauca and ofC. scorpioides. New glycosides alloglaucoside and scorpiosidol

Two new glycosides have been isolated from the seeds ofCoronilla glauca L. and C. scorpioides Koch: 3-(0-D-glucopyranosyloxy)-14. 15-dihydroxy-19-oxo-5-card-20(22)-enolide (alloglaucoside) and 3-(-D-gluco-ucofuranosyloxy)-5,14,19-trihydroxy-5-card-20(22)-enolide (scorpiosidol), together with a glycoside previously unknown for theCoronilla genus — 3-(-D-glucopyranosylo)g)-14-hydroxy-5-card-20(22)-enolide (desglucouzarin) and known aglycons (corotoxigenin, alloglaucotoxigenin, coroglaucigenin) and glycosides (glucocorotoxigenin, coronillobioside, glucocoroglaucigenin, coronillobiosidol and scorpioside).Ukraine Pharmaceutical Academy, Kharkov–2. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 372–376, May–June, 1996. Original article submitted August 14, 1995.     

Steroids of the furostan and spirostan series from Nolina microcarpa II. structures of nolinospiroside D and nolinofurosides D, E, and F

Proofs are given of the structures of two new glycosides of the furostan series isolated from the leaves of the plantNolina microscarpa S. Wats. (family Dracaenaceae). Nolinofuroside D is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-galactopyranoside 26-O--D-glucopyranoside (I), and nolinofuroside F is (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside 3-O--L-rhamnopyranoside (VII). The latter was characterized as its 22-O-methyl ether (VIII). Nolinofuroside E (IV) has the structure of (25S)-furost-5-ene-1,3,22,26-tetraol 26-O--glucopyranoside 1-O-[O--L-rhamnopyranosyl-(12)--D-fucopyranoside], which followed from the structure of the fermentation product (VI). The products of the fermentation of the above-named compounds were present in the plant in only trace amounts. Only one of them — nolinospiroside D (III) — has not been described previously. This monoside of the spirostan series is (25S)-spirost-5-ene-1,3-diol 1-O--D-galactopyranoside.M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 678–686, September–October, 1991.     

Steroid glycosides ofNicotiana tabacum seeds I. The structures of nicotianosides A, B, and E

Two steroid glycosides of the spirostan series — nicotianosides A and B — and one glycoside of the furostan series — nicotianoside E — have been isolated from the seeds ofNicotiana tabacum L. Nicotianoside A is (25S)-5-spirostan-3-ol 3-O--D-glucopyranoside, nicotianoside B is (25S)-5-spirostan-3-ol 3-O-[O--L-rhamnopyranosyl-(12)-gb-D-glucopyranoside], and nicotianoside E is (25S)-5-furostan-3,22,26-triol 26-O--glucopyranoside 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside].Institute of Genetics, Academy of Sciences of the Republic of Moldava, Kishinev, ul. Lesnaya, 20. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 737–742, November–December, 1994.     

Triterpene glycosides of Astragalus and their genins. XXIV. Cycloorbicoside G from Astragalus orbiculatus

A bisdesmosidic glycoside — cycloorbicoside G — has been isolated from the epigeal parts of the plantAstragalus orbiculatus Ledeb. (Leguminosae), and on the basis of chemical transformations and spectral characteristics its structure has been established as (23R,24S)-16,23;16,24-diepoxycycloartane-3,7,25-triol 25-O--D-glucopyranoside 3-O--D-xylopyranoside.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 837–842, November–December, 1987.     

Effect of intramolecular rotational reorganization of reagents on the ratio between free energies of activation and reaction

Conclusions The relationship between the free energies of activation G and reaction G_o for proton transfer processes have been analyzed, taking into account the effect of hindered rotation of the reagents. We have shown that the considered effect can considerably affect the shape of the G=f(G_o) curve.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 77–81, January 1989.     

Reaction of methylmagnesium iodide with steroid keto oxides

Summary The reaction of the 3-acetate of the 20-ketal of 16,17-oxido-⁵-pregnenol-3-one-20 with methylmagnesium iodide and subsequent hydrolysis of the reaction product yielded 16-methyl-⁵-pregnenediol-3 –17-one –20. 18-Nor-17-methyl-17-iso-^5.11-pregnadienediol-3,16-one-20 was formed as a by-product.