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1.
Summary (Z)-Narceine imide (1) reacted with 1,2-epoxypropane to narceone imide (2) and with an excess of epoxide to N-(2-hydroxypropyl)narceone imide (3). Cyclization of3 in acidic media afforded two isomers of 8,14-dimethyl-11,12-methylenedioxy-3,4,10-trimethoxyindano[1,2:2,3]morpholino[3,4-a]isoindolin-5-ones16 and17 which differed in the spatial orientation of the C-8-CH3. Narceonic acid (18) cyclized into the isochroman-3-spiro-3-phthalide derivative19.
Reaktion des (Z)-Narceinimid mit 1,2-Epoxypropan
Zusammenfassung (Z)-Narceinimid (1) reagierte mit 1,2-Epoxypropan zu Narceonimid (2) und bei Überschuß von Epoxid zu N-(2-Hydroxypropyl)narceonimid (3). Cyclisierung der letztgenannten Verbindung in Anwesenheit von Mineralsäuren fürhrte zu zwei Indano[1,2:2,3]morpholino[3,4-a]isoindol-5-on-Isomeren16 und17. Narceonsäure (18) wurde zu dem Isochroman-3-spiro-1-phthalid19 umgewandelt.
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2.
Two new samples of poly(amide–imide)/montmorillonite reinforced nanocomposites containing N,N′-pyrromellitoyl-bis-l-phenyl acetic acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide–imide) (PAI) 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N′-pyrromelitoyl-bis-l-phenyl acetic acid 1 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 10% and 20% silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using UV–vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.  相似文献   

3.
Several new steroid derivatives have been synthesised by the reaction of steroid-amino acid conjugates with N,N′-dicyclohexyl-carbodiimide. Selectivity of the reaction was found to depend greatly on the properties of the amino acid moiety. While the reaction of the glycine derivative led to the corresponding 5(4H)-oxazolone, an unusual imide formation together with an N-acylurea side product was observed in the case of conjugates of l-alanine, l-phenylalanine and l-methionine. The structures of the new products, steroidal imide and N-acylurea derivatives, were determined by various spectroscopic methods.  相似文献   

4.
Streptomyces sp. XT-11989 produces a mixture of two antibiotics with litmus-like indicator properties. One of them was shown to be identical with granaticin, the other was identified as [1S,3S,4S,7R,9R,10S,13R]-4,7,9,10-tetrahydro-5,12-dioxo-4, 6,10,11,13-pentahydroxy-1,9-dimethyl-(1H,3H)-7,10-ethanonaphtho[2,3-c: 6,7-c]dipyran-3-acetic acid and termed granaticinic acid. Microbial production and nuclear magnetic resonance data of these antibiotics are discussed and the antibacterial properties of the antibiotics are compared.
Mikrobielle produkte. II. Granaticinsäure, ein neues Antibiotikum von einem thermophilen Streptomyceten
Zusammenfassung Der Streptomycetenstamm XT-11989 produziert eine Mischung von zwei Antibiotika mit Lakmus-ähnlichen Indikatoreigenschaften. Eines dieser Antibiotika erwies sich als Granaticin, das andere wurde als [1S,3S,4S,7R,9R,10S,13R]-4,7,9,10-tetrahydro-5,12-dioxo-4,6,10,11,13-pentahydroxy-1,9-dimethyl-(1H,3H)-7,10-ethanonaphto[2,3-c: 6,7-c]dipyran-3-essigsäure identifiziert und Granaticinsäure benannt. Mikrobiologische Produktion und Kernresonanzdaten dieser antibiotika werden besprochen und ihre antibakteriellen Eigenschaften verglichen.
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5.
Two new neodymium complexes, [Nd2(abglyH)6(2,2′-bipy)2(H2O)2] · 4H2O 1 and {[Nd(abglyH)3(H2O)2] · (4,4′-bipy) · 7H2O}n 2 (abglyH2 = N-P-acetamidobenzenesulfonyl-glycine acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been synthesized and their structures have been measured by X-ray crystallography. In 1, nine-coordinated Nd(III) ions are bridged by two synsyn bidentate and two tridentate bridging carboxylate groups from four different abglyH anions to form dinuclear motifs, which are further connected into a 3-D supramolecular framework via hydrogen bonds between the binuclear motifs and the uncoordinated water molecules. In 2, eight-coordinated Nd(III) ions are linked by six carboxylate groups adopting a synsyn bidentate bridging fashion to form a 1-D inorganic–organic alternating linear chain. These polymeric chains generate microchannels extending along the a direction, and these cavities are occupied by discrete tetradecameric water clusters, which interact with their surroundings and finally furnish the 3-D supramolecular network via hydrogen bonds. At the same time, π–π stacking interactions between benzene rings from abglyH anions also play an important role in stabilizing the network.  相似文献   

6.
A series of new poly(amide–imide)s (PAIs, series III ) with good processability and characteristics was synthesized by utilizing organosoluble polyimide (PI, 6FDA–PI series) to improve poor‐solubility polyamide (PA, PTPA series), which used terephthalic acid (TPA) as a monomer. The III series PAIs were synthesized starting from the 2 : 1 molar ratio of aromatic diamines ( I ) and 6FDA to prepare imide ring‐preformed diamines ( II ) and then reacted with equimolar amount of TPA by direct polycondensation. Furthermore, by adjustment of the stoichiometry of the I , II, and TPA monomers, PAIs IV having various components were prepared. Most of the resulting PAIs having inherent viscosities between 0.70 and 1.74 dL/g were obtained in quantitative yields, and they were readily soluble in polar solvents such as N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidone, dimethylformamide, and dimethyl sulfoxide. All of the soluble PAIs afforded transparent, flexible, and tough films. The glass‐transition temperatures of PAIs III were in the range of 236–256 °C, and the 10% weight loss temperatures were recorded at 522–553 °C in nitrogen. The char yields of the III series polymers in nitrogen atmosphere were all higher than 56% even at 800 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 93–104, 2001  相似文献   

7.
In this study, the fatty acid contents of some Astragalus L. (Fabaceae) species from Turkey were determined by GC and GC-MS techniques. The seed oils of Astragalus sp. (A. echinops Aucher ex. Boiss., A. subrobustos Boriss., A. jodostachys, Boiss. & Buhse., A. falcatus Lam., A. fraxinifolius DC.) contained linolenic (between 23–41.%), linoleic (23–37%), and oleic acids (8–19%) as the major components. Fatty acid composition of the studied Astragalus taxa showed uniform fatty acid patterns. Palmitic and stearic acids were the major saturated fatty acids in the seed oils. The amounts of unsaturated fatty acids were higher than saturated fatty acids. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 526–528, November–December, 2006.  相似文献   

8.
A novel tetraimide dicarboxylic acid was synthesized with the ring‐opening addition of 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride, 4,4′‐oxydianiline, and trimellitic anhydride in a 1/2/2 molar ratio in N‐methyl‐2‐pyrrolidone followed by azeotropic condensation to tetraimide dicarboxylic acid. A series of poly(amide imide imide)s (PAIIs) with inherent viscosities of 0.8–1.1 dL/g were prepared from tetraimide dicarboxylic acid with various aromatic diamines by direct polycondensation. Most of the PAIIs were readily soluble in a variety of amide polar solvents and even in less polar m‐cresol and pyridine. Solvent‐cast films had tensile strengths ranging from 99 to 106 MPa, elongations at break ranging from 8 to 13%, and initial moduli ranging from 2.0 to 2.3 GPa. The glass‐transition temperatures of these PAIIs were recorded at 244–276 °C. They had 10% weight losses at temperatures above 520 °C in air or nitrogen atmospheres. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1092–1102, 2002  相似文献   

9.
Foldamer population of imide triads derived from (R,R)-1,2-diaminocyclohexane was studied with the use of 1H NMR and CD spectroscopy, as well as computational modeling. Two stable foldamers of C and S shape, having correspondingly M and P helicity, are found to differ very little in energy. However, their interaction with the solvent results in significant shift of the equilibrium. For the interaction with aromatic solvent molecules a sandwich-type donor-acceptor model, stabilizing the S foldamer, is proposed. The limitations of the NMR and CD methods for studying the foldamer equilibrium in solution are discussed, pointing to the inadequacy of static computational models of CD spectra, not including the effect of rotation of the imide chromophores in the dynamic model of real molecules.  相似文献   

10.
N-Substituted amides of 2-cyanopenta-2E,4-dienoic acid were synthesized by condensation ofN-substituted cyanoacetamides with acrolein in a dioxane-DMSO solution in the presence of Zn(OAc)2·2H2O as a condensing agent. X-ray diffraction study of 3-methylanilide of 2-cyanopenta-2E,4-dienoic acid (2d) demonstrated that the crystal structure of this compound is similar to that of 2-cyanopenta-2E,4-dienoic acid studied previously. However, the presence of themeta-tolyl substituent in molecule2d apparently results in the fact that the β-structure, which is typical of 2-cyanopenta-2E,4-dienoic acid, does not exist in the crystalline phase of2d. Henkel Kommanditgesellschaft auf aktien, Deutschland, D-40191 Dusseldorf, Henkelstrasse, 67. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 933–937, May, 1999.  相似文献   

11.
Amido- and aminophosphites and hydrospirophosphoranes can be used as ligands in the Pd-catalyzed allylation of ethyl malonate with ethyl (3-phenylprop-2-enyl) carbonate. Bidentate ligands (RO)2P--O(CH2)n--NR"2 (n = 2 and 3) were found to be the most effective ligands.  相似文献   

12.
The component composition of essential oils produced by steam distillation from flower heads, leaves, and stems of Salvia anatolica (Lamiaceae), a recently described new species endemic from Turkey, was studied by GC/FID and GC/MS. A total of 127 volatile components representing 96% of the oil was identified in essential oil from flower heads and leaves. It was found that the principal oil components of flower heads and leaves were α-pinene (10.9%), β-pinene (6.7%), α-copaene (6.3%), heptacosane (6.2%), and hexadecanoic acid (5.0%). A total of 109 volatile compounds representing 87.9% of the oil was characterized in essential oil isolated from stems. The principal oil components of stems were identified as hexadecanoic acid (27.2%), tetradecanoic acid (15.2%), dodecanoic acid (5.5%), and α-copaene (5.0%). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 552–555, November–December, 2007.  相似文献   

13.
A novel compound, biotinylated 18β-glycyrrhetinic acid (BGA), was synthesized. It is a compound of 18β-glycyrrhetinic acid linked with biotin. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 266–267, May–June, 2006. An erratum to this article is available at .  相似文献   

14.
The potentialities of new ionic liquids (ILs) based on choline were evaluated as an electrophoretic medium in capillary electrophoresis for the analysis of alkaline and alkaline earth cations (Li+, K+, Na+, Cs+, Mg2+, Ba2+, Ca2+, and Sr2+) with indirect UV detection. Two types of capillaries were tested: an untreated fused silica and fused silica coated with a film of polyvinylalcohol. The coated capillary proved to be the best adapted for the metal ions studied. Moreover, it appeared that the nature of the ionic liquid anion influenced the baseline stability, and the bis(trifluoromethylsulfonyl) imide (NTf2 ) anion seemed to be the most efficient. These preliminary studies led us to synthesize a new ionic liquid, 2-hydroxy-N,N,N-trimethyl-1-phenylethanaminium NTf2 (phenylcholine NTf2). This liquid was able to act as the running electrolyte and probe, generating the background signal in indirect UV light and consequently simplifying the electrophoretic medium. Excellent baseline stability, good reproducibility, as well as good sensitivity of detection were obtained with this new ionic liquid. Thus, 510,000 plates/meter for Li+ with 40 mM IL were successfully obtained. The optimal concentration of IL was 20 mM with a detection limit ranging from 28 μg L−1 for Li+ to 1,000 μg L−1 for Cs+. This method (phenylcholine NTf2 with polyvinylalcohol capillary) was applied to analyze different commercial source and mineral waters. Finally, the potentiality of this ionic liquid in nonaqueous capillary electrophoresis was explored. The use of phenylcholine NTf2 with a fused silica capillary, in pure methanol medium and in the presence of acetic acid, made it possible to obtain separation selectivity different from that obtained in aqueous medium.  相似文献   

15.
A new synthesis of octadeca-2E,13Z-dienylacetate from 10-undecenoic acid is developed by constructing the carbon framework of the pheromone in the key step and introducing the 2E double bond by Doebner condensation of hexadec-11-ynal and malonic acid.Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, 450054, Ufa, prospekt Oktyabrya, 71, fax: (3472) 35 60 66. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 164–166, March–April, 2000.  相似文献   

16.
Escherichia coli strain NZN111, which is unable to grow fermentatively because of insertional inactivation of the genes encoding pyruvate: formate lyase and the fermentative lactate dehydrogenase, gave rise spontaneously to a chromosomal mutation that restored its ability to ferment glucose. The mutant strain, named AFP111, fermented glucose more slowly than did its wild-type ancestor, strain W1485, and generated a very different spectrum of products. AFP111 produced succinic acid, acetic acid, and ethanol in proportions of approx 2:1:1. Calculations of carbon and electron balances accounted fully for the observed products; 1 mol of glucose was converted to 1 mol of succinic acid and 0.5 mol each of acetic acid and ethanol. The data support the emergence in E.coli of a novel succinic acid:acetic acid:ethanol fermentation pathway.  相似文献   

17.
Torlon®, a polyamide–imide polymer, was used for high-pressure CO2 separations, as it can form inter- and intra-chain hydrogen bonding that may provide stability against plasticization. Asymmetric hollow fiber membranes with a defect-free selective skin were successfully formed from Torlon® using a dry–wet spinning process. Dope and spinning parameters were optimized to obtain these fibers, which had CO2/CH4 selectivity of 44 and O2/N2 selectivity of 7.7. These selectivities are about 85% of the intrinsic (dense film) value of 52 for CO2/CH4 and 90% of the intrinsic value of 8.3 for O2/N2, respectively. Based on analyses presented, the reduced selectivities are attributed to substructure resistance rather than actual skin layer defects. Macrovoids, which compromise the strength of the fiber, were reduced by increasing the polymer concentration. The resulting fiber could withstand up to 2000 psi of N2, and a CO2 permeation study indicates that this fiber can perform selective separations under supercritical conditions of 1100 psi of CO2 at 35 °C.  相似文献   

18.
Treatment of acetylated phenyl thioglycoside of N-acetylneuraminic acid with m-chloroperbenzoic acid (MCPBA) in CH2Cl2 affords quantitatively mixtures of the respective sulfone and glycal free from the sulfoxide. The outcome of the reaction does not depend on the anomeric configuration of the starting thioglycoside. The sulfone can be selectively prepared (yield 100%) by oxidation with an excess of MCPBA and NaHCO3. In the presence of pyridine (2 equiv.) and MCPBA (2 equiv.), the major product is glycal (yields 81—88%). This version of the reaction can be regarded as a new method for the preparation of sialic acid glycals.  相似文献   

19.
AnO,N-dialkylation product, 1-methyl-5-metlioxy-6-oxo-1,6-diliydropyridine-3 carboxylic acid, is formed in the reaction of 5,6-dihydroxynicotinic acid with dimethylsulfate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1554–1555, June, 1996.  相似文献   

20.
Condensation of 4-bromomethylquinoline derivatives1 a-1 c with glycine and thioglycolic acid gave the corresponding quinolylmethylglycine and quinolylmethylthioacetic acid derivatives2 a-2 c and2 d-2 f, respectively. Cyclization of2 a-2 f was affected either by polyphosphoric acid or concentrated sulphuric acid to give3 a-3 f. Chlorination of2 a-2 f and3 a-3 f were also accomplished.
Die Reaktivität von 4-Brommethylchinolin-Derivaten gegenüber Glycin und Thioglycolsäure. Ein neues Ringsystem
Zusammenfassung Die Reaktion von 4-Brommethylchinolin-Derivaten1 a-c mit Glycin und Thioglycolsäure gab die entsprechenden Kondensationsprodukte2 a-c und2d-f.2 a-f konnten mit Polyphosphorsäure bzw. mit konzentrierter Schwefelsäure zu Benzo[c]-2,6-naphthyridinen3 a-f zyklisiert werden.2 a-f und3 a-f waren einer Chlorierung (POCl3) zugängig.
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