Synthesis of 2,3,7,8-tetramethyldibenzofuran

3,4,3,4-Tetramethyldiphenyl ether readily forms 2,2-dihalo derivatives on bromination and iodination. Heating 2,2-diiodo-4,5,4,5-tetramethyldiphenyl ether with copper powder or oxidation, of 2,2-dilithio-4,5,4,5-tetramethyldiphenyl ether gives 2,3,7,8-tetramethyldibenzofuran, the structure of which was proved by alternative synthesis from 2,2-dinitroand 2,2-diamino-4,5,4,5-tetramethyldiphenyls.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1599, December, 1972.     

Discrimination between catalyst deactivation mechanisms by kinetic measurements in open systems

Two competitive mechanisms of catalyst deactivation caused by either the starting substance or the reaction product are considered. The problem of the possible discrimination between these mechanisms according to kinetic measurements in open systems can be solved by a numerical experiment on a computer.

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Die γ-Bestrahlung von synthetischem β-Carotin

Zusammenfassung Das feste -Carotin ist gegen -Strahlung ziemlich stabil. Bei Bestrahlung unter Sauerstoffbegasung treten deutliche -Carotin-Verluste erst bei der hohen Dosis von 12 Mrad auf; bei Bestrahlung an der Luft werden ähnliche Radiolyseerscheinungen erst durch wesentlich höhere Strahlendosen ausgelöst. Spaltungsprodukte, die bei 12 Mrad und Sauerstoffbegasung auftraten und dünnschichtchromatographisch aufgetrennt werden konnten, waren Isozeaxanthin, -Carotin-5,6-5, 6-diepoxid, -Carotin-5,8-5,8-diepoxid, -Apo-12-carotinal, -Apo-10-carotinal, 3,3,6-Trihydroxy--carotin-5,8-epoxid und Vitamin-A-Alkohol. Es ist bemerkenswert, daß ein Teil der Radiolyseprodukte (z. B. Vitamin-A₁-Alkohol, -Apo-12-carotinal und -Apo-10-carotinal) Vitamin-A-Wirksamkeit besitzt.

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The -Irradiation of synthetic -carotene. Some physico-chemical and thin-layer chromatographic studies of radiolysis products

Solid -carotene is remarkably stable to -irradiation. In an oxygen atmosphere doses as high as 12 Mrad were required to bring about significant losses of -carotene, whereas in air even larger doses had to be applied in order to effect a comparable degree of radiolysis. Cleavage products which arose in O₂ at a dose of 12 Mrad and which could be separated from each other by thin-layer chromatography were isozeaxanthin, -carotene-5,5-5,6-diepoxide, -apo-12-carotenal, -apo-10-carotenal, 3, 3, 6-trihydroxy--carotene-5,8-epoxide and vitamin A₁. It is notable that some of the radiolysis products (e.g., vitamin A₁, -apo-12-carotenal and -apo-10-carotenal) possess vitamin A activity.

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Herrn Prof. Dr.O. Hromatka zum 65. Geburtstag gewidmet.     

Flavonoids ofHaplophyllum perforatum. New glycosides of limocitrin

Two new glycosides of limocitrin have been isolated from the epigeal part ofHaplophyllum perforatum (M. B.) Kar. et Kir. On the basis of chemical transformations and spectral characteristics the structures of the substances isolated have been established as 7-(6-acetyl--D-glucopyranosyloxy)-3,4,5-trihydroxy-3,8-dimethoxyflavone and 7-[0--L-rhamnopyranosyl-(1 2)--D-glucopyranosyloxy]-3,4,5-trihydroxy-3,8-dimethoxyflavone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 192–196, March–April, 1985.     

Spektrophotometrische Bestimmung von Dehydrokondensationsprodukten der Pyrazine und Chinoxaline

Zusammenfassung Die Absorptionsspektren folgender Verbindungen: Chinoxalin, 2,2-Dichinoxalyl, 2-Methylchinoxalin, 3,3-Dimethyl-2,2-dichinoxalyl, Pyrazin, 2,2-Dipyrazyl, 2-Methylpyrazin und 5,5-Dimethyl-2,2dipyrazyl wurden in Methanol im Bereich von 225–360 nm bestimmt.Eine Methode zur quantitativen Bestimmung der genannten Verbindungen wurde ausgearbeitet, um den Herstellungsprozeß von 2,2Dichinoxalyl, 3,3-Dimethyl-2,2-dichinoxalyl, 2,2-Dipyrazyl und 5,5-Dimethyl-2,2-dipyrazyl aus den entsprechenden Monomeren durch direkte Photometrierung von Proben der Reaktionsgemische, die in einem beliebigen Stadium der Synthese dem Reaktor entnommen wurden, verfolgen zu können.

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Spectrophotometric determination of dehydrocondensation products of pyrazines and quinoxalines

Summary The absorption spectra of the following compounds: quinoxaline, 2,2-diquinoxalyl, 2-methylquinoxaline, 3,3-dimethyl-2-2-diquinoxalyl, pyrazine, 2,2-dipyrazyl, 2-methylpyrazine and 5,5-dimethyl-2,2-dipyrazyl were determined in methanol in the region of 225–360 nm. A method was developed for the quantitative determination of these compounds in order to be able to follow the preparation methods of 2,2-diquinoxalyl, 3,3-dimethyl-2,2-diquinoxalyl, 2,2-dipyrazyl and 5,5-dimethyl-2,2-dipyrazyl from the corresponding monomers through direct photometration of samples of the reaction mixture, which can be taken from the reactor at a selected stage of the synthesis.

     

Investigations in the field of the chemistry of 2-hetarylbenzimidazoles. 6. Synthesis and properties of 1-methyl-2-(2′-selenienyl)benzimidazole

2-(2-Selenienyl)benzimidazole has been synthesized by a Weidenhagen reaction and converted into the N-methylated derivative. Electrophilic-substitution reactions (nitration, sulfonation, bromination, chloromethylation, and acylation) in the selenophene ring have been studied. It has been shown that the substituent enters the position of the selenophene ring in most cases. The bromination of 1-methyl-2-(2-selenienyl)benzimidazole in acetic acid produces the 3,5-dibromo derivative, whereas 1-methyl-5(or 6)-bromo-2-(3,5-dibromo-2-selenienyl)benzimidazole is obtained in polyphosphoric acid.For Report 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1531–1534, November, 1983.     

Transformed steroids. 160. Reaction of 20,20-dimethoxy-16α,17α-epoxypregn-5-ene-3β, 21-diol-20-one with pyridine thiocyanate and carbethoxyhydrazine

Conclusion The reaction of 20,20-dimethoxy-16,17-epoxypregn-5-ene-3,21-diol-20-one with pyridine thiocyanate in the presence of carbethoxyhydrazine proceeds by two competing paths: cisopening of the oxide ring by a -SCN ion at the C¹⁷ atom, and substitution of one of the methoxyl groups by -NCS ion. As a result 2,20-dicarbethoxyhydrazones of pregn-5-ene-3,21-diol-20-one-[17,16-d]-1,3-oxathiolan-2-one and 20-methoxy-16,17-epoxypregn-5-ene-3-ol-[20,21-d]-1,3-oxazolidine-2-thione are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 911–914, April, 1987.     

Synthesis of novel heterocycles from thiazolecarbohydrazides

Cyclization of 2-methyl (or -phenyl)-5-phenylthiazole-4-carbohydrazides (1) and (2) under various conditions gives differing oxadiazoles: 2-(2-substituted-5-phenyl-4-thiazolyl)-1,3,4-oxadiazole-5-thiones (7) and (8), and 2-(2-substituted-5-phenyl-4-thiazolyl)-1,3,4-oxadiazoles (9) and (10). Cyclodehydration of thiazolecarbonyl-thiosemicarbazides (3)–(6) with NaOH givesthe 3-(2-substituted-5-phenyl-4-thiazolyl)-4-substituted-4H-5-mercapto-1,2,4-triazoles (11)–(14), while H ₃ PO ₄ gives the 2-(2-substituted-5-phenyl-4-thiazolyl)-5-phenylamino-1,3,4-thiadiazoles (15) and (16).A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 679–683, March, 1992.     

Structure of some components of the roots of Prangos ferulacea

Summary From a methanolic extract of the roots ofPrangos ferulacea (L) Lindl., growing in the Nakhichevan ASSR, in addition to the compounds found previously, another six substances (I–VI) have been isolated, of which (I) and (VI) have been identified as, respectively, meransin hydrate monoacetate, found for the first time in nature, and umbelliferone: and in the study of a crystalline mixture obtained from the resin of the roots of the plant under investigation collected in Armenia, two coumarins — (VII) and (VIII) — have been isolated.On the basis of a study of IR, NMR, and mass spectra and chemical properties, the structures of the six new cumarin derivatives (II–V, VII, and VIII) have been established. Compound (II) has the structure of 8-(3-methylbutenyloxy)furo-2,3:7,6-coumarin and has been called feruliden; (III) is 7-hydroxy-8-(3-hydroxy-2-senecioyloxyisopentyl) coumarin and has been called ferudiol; (IV) is 7-hydroxy-8-(3-methoxy-2-senecioyloxyisopentyl) coumarin; (V) is 5-[1-(2,3-dihydroxy-3-methylbutyroyloxy)-1-methylethyl]-4,5-dihydrofuro-2,3:7,6-coumarin and has been called lindiol; (VII) is 8-(2-hydroxy-3-methylbut-3-enyloxy)-7-methoxycoumarin and has been called ferudenol; (VIII) is 7-methoxy-8-(3-methyl-2-oxobut-3-enyl)coumarin and has been called prangone.Leningrad Sanitary-Hygenic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 568–574, September–October, 1974.     

Chemical microscopy of platinum metals and gold: Reactions with 4,4′-dipyridyldihydrochloride

Summary It has been shown that an acid solution of 4,4-dipyridyldihydrochloride can serve to identify low concentrations of most of the platinum metals and gold in 1-N hydrochloric acid solutions of their chlorides by the separation of characteristic micro crystalline precipitates. The reagent was most effective for palladium(II) and platinum(IV), which could be identified in a 20-l drop of sample containing less than 0.6g of metal. Under the conditions imposed, rhodium (III) was the only platinum metal which failed to yield a precipitate. By contrast, under similar conditions 2,2-dipyridyl failed to yield a crystalline precipitate with rhodium(III), ruthenium (III), and iridium(III). Cupric ion caused the separation of a crystalline complex with 4,4-dipyridyl reagent only at a relatively high metal concentration.

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Zusammenfassung Eine saure Lösung von 4,4-Dipyridyldihydrochlorid eignet sich zum Nachweis geringer Konzentrationen der meisten Platinmetalle und des Goldes in 1-n salzsauren Lösungen ihrer Chloride durch charakteristische Mikrokristallfällungen. Am wirksamsten ist das Reagens gegenüber Pd(II) bzw. Pt(IV), von denen sich weniger als 0,6g in einem 20-l-Tropfen nachweisen lassen. Unter den angegebenen Bedingungen gibt Rh(III) als einziges Platinmetall keinen Niederschlag. Dagegen gibt 2,2-Dipyridyl unter diesen Bedingungen außer mit Rh(III) auch mit Ru(II) und Ir(III) keine kristalline Fällung. Kupfer(II)-ionen bilden mit 4,4-Dipyridyl erst in relativ hoher Konzentration eine kristallisierte Komplexverbindung.

     

Preparation,spectral and thermal studies of neodymium zirconyl oxalate hexahydrate

Neodymium zirconyl oxalate (NdZrOX) is prepared and characterized by chemical analysis and ir spectral studies. Its thermal decomposition has been investigated by using DTA, TG, DTG, X-ray diffraction and ir spectroscopy. On the basis of thermogravimetry and isothermal studies a probable mechanism for the decomposition is proposed. The decomposition proceeds mainly through three stages: i) dehydration between RT-413 K, ii) decomposition of oxalate between 413–943 K and iii) decomposition of the carbonate between 1028–1235 K to give a mixed oxide. The ir spectra and X-ray diffraction studies are made for identification of the intermediates. X-ray diffraction studies of the end product indicates that it belongs to cubic crystal system witha=11.520 Å.

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Zusammenfassung Neodymzirkonyloxalat (NdZrOX) wurde dargestellt und durch chemische Analyse und IR-spektroskopische Untersuchungen charakterisiert. Die thermische Zersetzung dieser Verbindung wurde mittels DTA. TG, DTG, Röntgendiffraktometrie und IR-Spektroskopie untersucht. Basierend auf Ergebnisse der Thermogravimetrie und isothermer Methoden wird ein möglicher Zersetzungsmechanismus vorgeschlagen. Die Zersetzung verläuft im wesentlichen über drei Stufen: i) Dehydratisierung zwischen Zimmertemperatur und 413 K, ii) Zersetzung des Oxalats zwischen 413 und 943 K und iii) Zersetzung des Carbonats zwischen 1028 und 1235 K unter Bildung eines Mischoxides. IR-spektroskopische und röntgendiffraktometrische Untersuchungen wurden zur Identifizierung der Zwischenprodukte ausgeführt. Die röntgendiffraktometrische Untersuchung des Endproduktes ergibt eine kubische Zelle mita= 11.520 Å.

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-. , , , . . , , : / 413 , / 413943 / 1028–1235 . - . - , =11.520 Å.

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One of the authors (VBR) is grateful to CSIR (India) for the senior research fellowship.     

Entropy in dissimilarity and chirality measures

Within the prospect of quantifying the geometrical dissimilarity of molecular models on the basis of a thermodynamical formalism, the algebra of stereogenic pairing equilibria is reviewed and applied to molecular geometry: developing Rassat's proposition, an interaction energy of two figures F and F is taken as proportional tod _H ^Emphasis>/2 (F, F), whered _H denotes the Hausdorff distance. IfG is a group of rotations in E _n the geometrical version of the general equation (E) of the chemical algebra defines a distance extensionD _p(F,F) ofd _H(F,F), which is independent of the orientations of F and F, and where the coefficientp is interpreted as the reciprocal of a temperature-like parameter:p 1/T. At K (p = ), no formal entropy contributes to the definition of the uniform distanceD . At K (p = 0), the discrimination between homo- and hetero-pairing of figures by the harmonic distance Do is averaged over orientation states. Temperature-dependent chirality measuresc _p are derived fromD _p, andc is analogous to Mislow's chirality measure. If T and oT are normalized enantiomorphic triangles with coincident centroids inE ₂,c _p(T) =D _p (T, T) is calculated forp = 0 andp = , and discussed for 0 <p < . Finally, the Hausdorff interaction model is putatively related to energy profiles versus dihedral angle inmeso- anddl-molecules.     

Mono and dinuclear cationic rhodium(I) and iridium(I) complexes with sulphur donor and group Vb ligands

Summary Rhodium(I) and iridium(I) mixed complexes of the formulae [M(diolefin)LL]ClO₄, [M(diolefin)L₂L]ClO₄, [(diolefin)LIr(-L)₂IrL(diolefin)](ClO₄)₂, [(diolefin)LM(-L-L)ML'(diolefin)](ClO₄)₂, [(diolefin)Rh{-(L-L)}₂Rh(PPh₃)₂](ClO₄)₂ and [(diolefin)LIr{-(L-L)}₂IrL (diolefin)](C1O₄)₂, (L=monodentate sulphur ligand, L-L=bidentate sulphur ligand, L=group Vb ligand; M=Rh, diolefin=1,5-cyclooctadiene (COD) or 2,5-norbornadiene (NBD); M=Ir, diolefin=COD) are described.Author to whom all correspondence should be directed.     

Phthalocyaninartige Bor-Komplexe

Zusammenfassung Aus Halogenboranen und Organohalogenboranen (RBX ₂R=C₆H₅, Cl, Br;X=F, Cl, Br) sowie aus Organoboranen oder Thioboranen entstehen mit Phthalodinitril Triisoindolo-[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8,9a,9b]-hexaazaboraphenalene von denen die B–Cl- und B–F-Verbindungen näher charakterisiert werden.Dekaboran(14), Diboran(6) oder Boranaddukte von Stickstoffbasen liefern hingegen mit Phthalodinitril metallfreies Phthalocyanin.

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Triisoindolo[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8,9a,9b]-hexa-azaboraphenalene

Triisoindolo[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8, 9a,9b]-hexaazaboraphenalenes are obtained from the reactions of haloboranes and organohaloboranes (RBX ₂R=C₆H₅, Cl, Br;X=F, Cl, Br) as well as from organoboranes or thioboranes with phthalodinitrile. The B–Cl and B–F compound have been characterized by analyses, i.r.-, u.v.- and mass-spectrometry.Diborane(6), dekaborane(14) and amine-boranes, however, upon reaction with phthalodinitrile lead to high yields of metal free phthalocyanine.

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Herrn Prof. Dr.M. Pailer zum 60. Geburtstag gewidmet.     

Isoflavones of the roots of Lupinus luteus

Conclusions For the first time in the isoflavone series, a compound which has the structure of 5,7-dihydroxy-3,4-methylenedioxyisoflavone (3,4-methylenedioxyorobol) and two of its glucosides — 3,4-methylenedioxyorobol 7-O--D-glucoside and 3,4-methylenedioxyorobol 7-O--D-glucosylglucoside — and also a genistein C-monoglucoside, have been described. The isoflavones were isolated from the roots ofLupinus luteus L. by preparative chromatography on paper and on columns of polyamide. In addition, the previously known genistein, genistein 7-O--D-glucoside (genistin), and genistein 7-O--D-glucosylglucoside have been obtained.V. F. Kuprevich Institute of Experimental Botany, Academy of Sciences of the Belorussian SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 162–166, March–April, 1974.     

9-(2′,5′-Dimethyl-4′-pyridyl)fluorene in syntheses of fluorospirodihydrofuropyridine and pyridofluoranthene

1,2,5-Trimethyl-4-(9-fluorenylidene)piperidine, which is formed by condensation of fluorene with 1,2,5-trimethyl-4-piperidone, is converted catalytically to 9(2,5-dimethyl-4-pyridyl)fluorene, from which 2-methylpyrido[4,5-a]fluoranthene and its demethylated analog were obtained by catalytic dehydrocyclization. Oxidation of 9-(2,5-dimethy1-4-pyridyl)fluorene gave 9-(2,5-dimethyl-4-pyridyl)9-fluorenol and fluorene-9-spiro-4-(6-oxo-2-carboxypyrido[4,5-c]-4-6-dihydrofuran). 6-Methyl-2-phenyl-7-(9-fluorenyl)indolizine was synthesized by the Chichibabin method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1090, August, 1978.     

Coumarins of Seseli tenuisectum

Summary The herbSeseli tenuisectum has been found to contain — in addition to anomalin — another three coumarins (C-2, C-3, and C-4) which are derivatives of khellactone.On the basis of NMR, mass, and IR spectroscopy, the products of stepwise alkaline methanolysis and hydrolysis, and conversion into pteryxin, it has been established that two of them are isomeric monoesters of khellactone and angelic acid with the structures 3-angeloyloxy-4-hydroxy- and 4-angeloyloxy-3-hydroxy-3,4-dihydroxyseselin, respectively. They have been obtained in the individual state for the first time by thin-layer chromatography, which has enabled their IR spectra to be recorded.The lactone C-4 is a diester of khellactone with the structure 4-angeloyloxy-3-isovaleryloxy-3,4-dihydroseselin.We are the first to have found these substances in plants of the flora of the USSR.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 38–43, January–February, 1972.     

Investigations in the field of lipids

Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966