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1.
Summary From the roots ofSeseli grandivittatum, together with -sitosterol and (–)-3R-decursinol, found in nature for the first time, and its angelate, we have isolated two new compounds which we have called grandivittin and grandivittinol.On the basis of IR, PMR, and mass spectra and chemical transformations, the structure of 3-senecioyloxy-3,4-dihydro-3R-xanthyletin is proposed for grandivittin, and 7-hydroxy-6-(3-hydroxy-2-senecioyloxyisopentyl) coumarin for grandivittinol.Leningrad Sanitary-Hygienic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 640–646, September–October, 1977.  相似文献   

2.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research.  相似文献   

3.
Summary Complexes of adenosine-5-triphosphate, adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, cytidine-5-monophosphate and uridine-5-monophosphate with vanadyl ion, have been studied in the solid state by i.r. spectroscopy and magnetochemically. All complexes have normal magnetic moments, very close to the spin-only values. From the i.r. spectra it is suggested that the vanadyl ion is interacting with adenosine-5-triphosphate, through the N-1 of the purine ring, with adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, through the N-7 of the purine ring, with cytidine-5-monophosphate through the N-3 of the pyrimidine ring, and most probably through the phosphate group with uridine-5-monophosphate. The complexes of vanadyl ion with the nucleotides are probably polymeric.  相似文献   

4.
By the condensation of -halogenomethyl derivatives of pyrroles with -unsubstituted pyrroles the synthesis of the following unsymmetrical dipyrrolylmethanes has been effected: 5-benzyloxycarbonyl-5-ethoxycarbonyl-3, 3-di(-methoxycarbonylethyl)-4,4-dimethyl-2,2-dipyrrolylmethane (IIIa), 5-benzyloxycarbonyl-5-ethoxycarbonyl-3-(-methoxycarbonylethyl)-4, 4-diniethyl-3-n-propyl-2,2-dipyrrolylmethane(IIIb), 3-acetyl-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIIc), and 3-bromo-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIId). Hydrogenation of the unsymmetrical dipyrrolylmethanes IIIa, b, c, and d has given the corresponding monocarboxylic acids IVa, b, c, and d. The formylation of the dipyrrolylmethanemonocarboxylic acid IVa has given 5-ethoxycarbonyl-5-formyl-3,3-di(-methoxycarbonylethyl)-4, 4-dimethyl-2,2-dipyrrolylmethane (V).For communication II, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1045–1047, August, 1970.  相似文献   

5.
2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979.  相似文献   

6.
The compatibility of a lauric fat with several milk fat fractions (MF) was investigated. The enthalpy of crystallization was measured by differential scanning calorimetry (DSC). These values were related to the corresponding values calculated for an Ideal Blend. The different compatibility of the milk fat fractions with the lauric fat could be shown by this method very clearly.
Untersuchungen zur Mischbarkeit/Verträglichkeit von Milchfettfraktionen mit laurischen Fetten
Zusammenfassung Die Mischbarkeit/Verträglichkeit von Milchfettfraktionen mit einem laurischen Fett wurde differenzkalorimetrisch untersucht. Die Auswertung der Befunde bezieht sich auf die entsprechenden Rechnungswerte einer Idealen Mischung. Es wurde nachgewiesen, da sich diese Milchfette deutlich in ihrer Mischbarkeit unterscheiden.

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7.
Zusammenfassung Arylhydrazon-cyanacetylcarbamidsäureäthylester (I) wurde durch Einwirkung einer Na2CO3-Lösung auf 1-Aryl-5-cyan-6-azauracile (II)1,2 cyclisiert. Nitrile (II) wurden durch Addition von Hydroxylamin in entsprechende Amidoxime (III) übergeführt, welche durch Kochen mit Acetanhydrid die zugehörigen 1-Aryl-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracile (IV) lieferten.
Aryl hydrazone-cyanoacetylcarbamic acid ethyl esters (I) have been cyclized in Na2CO3 soln. yielding 1-aryl-5-cyano-6-azauraciles (II)1,2. Addition of NH2OH to the nitriles (II) gave the corresponding amidoximes (III), which by refluxing with Ac2O were converted to the corresponding 1-aryl-5-[5-methyl-1, 2, 4-oxdiazolyl(3)]-6-azauraciles (IV).
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8.
Summary 2-O-Ethyluracil and 2-O-ethylthymine were silylated with 1,1,1,3,3,3-hexamethyldisilazane and condensed in the presence ofTMS triflate with 2,3-dideoxy-3-fluoro-D-erythro-pentofuranoside, 3-azido-2,3-dideoxy-D-erythro-pentofuranoside, and 2,3-dideoxy-3-phthalimido--D-erythro-pentofuranose derivatives to give the corresponding 2-O-ethyl nucleosides. Deprotection with saturated methanolic ammonia afforded the 2,3-dideoxy-3-fluoro-2-O-ethyluridines, whereas 3-azido-2,3-dideoxy-3-O-ethyluridine was obtained by deprotection with tetrabutylammonium fluoride in tetrahydrofuran. 3-Amino-2,3-dideoxy-3-O-ethyluridine could be obtained only by treatment of the corresponding 3-azido nucleoside with triphenylphosphine in pyridine. 3-Deoxy-2-O-ethyl-3-fluorothymidine (6b) showed moderate activity against HIV-1.
Synthese von 2-O-Ethyl-Analogen von 3-Azido- und 3-Fluor-23-dideoxyuridinen und Bestimmung ihrer biologischen Aktivität gegenüber HIV
Zusammenfassung 2-O-Ethyluracil und 2-O-Ethylthymin wurden mit 1,1,1,3,3,3-Hexamethyldisilazan silyliert und in Gegenwart vonTMS-triflat mit 2,3-Dideoxy-3-fluoro-D-erythro-pentofuranosid, 3-Azido-2,3-dideoxy-D-erythro-pentofuranosid und 2,3-Dideoxy-3-phthalimido--D-erythro-pentofuranosederivaten zu den entsprechenden 2-O-Ethyl-Nucleosiden umgesetzt. Entfernung der Schutzgruppe mit gesättigter methanolischer Ammoniaklösung lieferte 2,3-Dideoxy-3-fluor-2-O-ethyluridin; 3-Azido-2,3-dideoxy-3-O-ethyl-uridin wurde durch Entschützung mit Tetrabutylammoniumfluorid in Tetrahydrofuran erhalten. 3-Amino-2,3-dideoxy-3-O-ethyl-uridin konnte nur durch Behandeln des entsprechenden 3-Azido-Nucleosids mit Triphenylphosphin in Pyridin hergestellt werden. 3-Deoxy-2-O-ethyl-3-fluor-thymidin (6b) zeigt geringe Aktivität gegenüber HIV-1.
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9.
Zusammenfassung Analog wie in vorherigen Mitteilungen1–4 wurden -Pyridyl-hydrazono-cyanacetylcarbamidsäureäthylester (1), 1-(-Pyridyl)-5-cyan-6-azauracil (2), 1-(-Pyridyl)-6-azauracil-5-carbonsäure (3), deren Thioamid (4), und Amidoxim (5), welches in 1-(-Pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6) überge-führt wurde, hergestellt.
-Pyridylhydrazono-cyanacetylcarbamic acid ethyl ester (1), l-(-pyridyl)-5-cyano-6-azauracil (2), 1-(-pyridyl)-6-azauracil-5-carboxylic acid (3), its thioamide (4) and amidoxime (5) were prepared as described in preceding communications. (5) was converted into l-(-pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6).
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10.
Conclusions The previously expressed theory that the tricyclic triethyl triphosphite of D-mannitol is 2-ethoxy-4, 5-bis-(2-ethoxy-1, 3, 2-dioxaphospholan-4-yl)-l,3,2-dioxa-4-phospholane was corroborated on the basis of the differential-thermal analysis and31P NMR data.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1390–1395, June, 1972.  相似文献   

11.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

12.
A study has been made of natural C-methylflavones and their dealkylated analogues: 5-hydroxy-4,7-dimethoxy-7-methylflavone (noreucalyptin); 4,5,7-trihydroxy-6-methylflavone; 5-hydroxy-4,7-dimethoxy-6,8-dimethylflavone (eucalyptin); 4,5-dihydroxy-7-methoxy-6,8-dimethylflavone (sideroxylin); 4,5,7-trihydroxy-6,8-dimethylflavone; 4,5,6-trihydroxy-3-methoxy-8-methylflavone (silpin) and 3,4,5,6-tetrahydroxy-8-methylflavone.All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 306–309, May–June, 1984.  相似文献   

13.
Mononuclear [Co(HL)2LCl)], [Co(LBF2)2LCl] or [Cu-(HL)2] H2L = {N,N-bis (4-N-phenylaza [15]crown-5)diaminoglyoxime} and a trinuclear, [Cu(L)2(CuL)2](NO3)2, complex of the ligand were synthesized and characterized. The mononuclear copper(II) species coordinates to two copper(II) ions through the deprotonated oximate oxygens to yield a trinuclear structure cis-bridged by the oximate groups, with 1,10-phenanthroline as an end-cap ligand. The terminal copper adopts an essentially planar configuration with the nitrogen atoms of H2L. The structure of the ligand and its complexes is proposed and formulated according to the elemental analyses, 1H- and 13C-n.m.r, i.r. and m.s. spectral data.  相似文献   

14.
Four Hg(II) complexes, containing as ligands 6-amino-5-nitrosouracil (AH), 6-amino-3-methyl-5-nitrosouracil (BH) or 6-amino-1-methyl-5-nitrosouracil (CH), have been synthesized and their thermal behaviour studied by TG and DSC techniques: Hg3Cl6(AH)4, HgCl2(BH)2· 2 H2O, HgCl2(BH)2 · H2O and HgC2· 2 H2O.The dehydration processes take place in only one step, with enthalpies in the range 40.2–60.0 kJ · mole–1 H2O.Pyrolytic processes start between 200 and 250°, in all cases the thermal stability of the corresponding pyrimidine derivative being lower than that of the free ligand. These processes finish between 600 and 750°, with no residue.
Zusammenfassung Vier 6-Amino-5-nitrosouracil (AH), 6-Amino-3-methyl-nitrosouracil (BH) oder 6-Amino-1-methyl-5-nitrosouracil (CH) als Liganden enthaltende Hg(II)-Komplexe wurden synthetisiert: Hg3Cl6(AH)4, HgCl2(BH)2 · 2 H2O, HgCl2(BH)2 · H2O und HgC2 · 2 H2O. Die Dehydratisierungsprozesse verlaufen in nur einem Schritt mit Enthalpien im Bereich von 40.2–60.0 kJ pro mol H2O. Pyrolitische Prozesse setzen zwischen 200 und 250° ein. In allen Fällen ist die thermische Stabilität der entsprechenden Pyrimidin-Derivate geringer als die der freien Liganden. Diese Prozesse sind zwischen 600 und 750° beendet, wobei kein Rückstand zurückbleibt.

g3l6()4, gl2( )2 · 2 2O, gl2()2 · 2O, g2 · 2 2, — 6- -5-, — 6--3- — 6---5- . , 40.2–60.0 · –1 2. 200 250° 600–750° - . , .
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15.
Summary Conformational properties of two nucleoside analogs, namely nebularine and isoguanosine have been investigated by using PCILO (Perturbative Configuration Interaction using Localized Orbitals) method. Nebularine (9--ribofurnosyl purine) is a naturally occurring purine nucleoside which is structurally similar to adenosine and it inhibits the growth of tumor cells and influenza B virus. Isoguanosine is one of the two naturally occurring analogs of guanosine. Both C2-endo and C3-endo sugar puckerings have been considered for both the molecules with preselected values of torsion angles around C2–O2 and C5–O5 bonds. The results indicate that nebularine has conformational preferences very similar to those of its parent nucleoside, adenosine; whereas the conformational properties of isoguanosine are very different from those of guanosine as well as adenosine. The important implications of these results have been discussed in terms of the biological activity of these molecules.  相似文献   

16.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
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17.
Zusammenfassung Die Synthese von geschützten 2,3-Dideoxy-2-hydroxymethyl-nucleosiden wird beschrieben. Die durch ein Mehrstufenverfahren aus Isopropylidenglycerol erhaltenen Nucleoside können als Bausteine zur Darstellung von Oligonucleotiden verwendet werden, deren 2- und 5-Positionen über eine Etherbrücke verbunden sind.
Synthesis of 2,3-dideoxy-2-hydroxymethyl nucleosides
Summary The synthesis of protected 2,3-dideoxy-2-hydroxymethyl nucleosides is presented. The nucleosides, obtained in a multi-step procedure starting from isopropylideneglycerol, may be used as building blocks for the synthesis of 2,5-ether linked oligonucleotides.
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18.
Sulfamides were synthesized via the reaction of cytisine with 4,4(5)-dibenzo-18-crown-6-disulfonyl-, 4-sec-butyl-4(5)-dibenzo-18-crown-6-sulfonyl-, and 4-acetyl-4(5)-dibenzo-18-crown-6-sulfonylchlorides. The structures of the prepared compounds were confirmed by PMR.  相似文献   

19.
A general approach to the solution of peak seperation problem applicable not only in nonisothermal kinetics, but also in chromatographic, spectroscopic and polarographic studies of catalysts is suggested.
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20.
Summary 1. In a study of the kinetics of the alkaline hydrolysis of flavone glycosides it has been found that derivatives of 3,3,4,5,7-pentahydroxyflavone hydrolyze faster than derivatives of 3,4,5,7-tetrahydroxyflavone and of 3,4,5,7-tetrahydroxy-3-methoxyflavone.2. In the hydrolysis of diglycosides of 3,3,4,5,7-pentahydroxyflavones the maximum amount of intermediate product is formed after 2 min (3,4,5,7-tetrahydroxyflavone glycoside), and in the case of 3,4,5,7-tetrahydroxy-3-methoxyflavone glycosides after 120–150 min.I. V. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 646–649, September–October, 1977.  相似文献   

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