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1.
Zusammenfassung Die Komplexbildung des p-Methylbenzamidoxims (pMB) mit Ni2+ wurde in neutraler und alkalischer Lösung spektrophotometrisch untersucht. In neutraler Lösung wird ein grüner Komplex 11 gebildet, dessen Bildungskonstante 1=1,12 ist. In alkalischer Lösung werden zwei Komplexe (11 und 12) gebildet mit Bildungskonstanten 1=4·105 und 2=0,2.
Nickel complexes with p-methyl benzamide oxime
The complex formation of p-methyl benzamidoxime with Ni2+ was studied spectrophotometrically in neutral and in alkaline solution. A green complex 11 is formed in neutral solution. Its formation constant is 1=1.12. In alkaline solution two complexes (11 and 12) are formed. Their formation constants are 1=4·105 and 2=0,2 resp.


Mit 6 Abbildungen  相似文献   

2.
4-(,-Dicarboethoxy--acetylamino) ethyl-7-aminobenzo-2,1, 3-thiadiazole (IV) and ethylene oxide form mainly the 7-(-hydroxyethyl) amino derivative (V); the 7- di (-hydroxyethyl) amino derivative VII was isolated in low yield. Action of POCl3 on compound VII gave the 7-di (-chloroethyl) amino derivative VIII, which was converted into 4-(-amino--carboxy)-ethyl-7 -di (-chloroethyl) aminobenzo-2, 1, 3-thiadiazole (IX). 5-(, -dicarboethoxy--acetylamino) ethyl-4-nitrobenzo-2, 1, 3-thiadiazole (XI) was converted to 5-(-carboxy--amino) ethyl-4-nitrobenzo-2, 1, 3-thiadiazole hydrochloride (XII), from which was prepared, by known routes, and in satisfactory yield, 5-(-carboxy--amino) ethyl-4-di (-chloroethyl)-aminobenzo-2, l, 3-thiadiazole hydrochloride (XVII).For Part XXXIX see [8].  相似文献   

3.
Cyclosiversigenin 6-O--L-rhamnopyranoside and 6-O--D-glucopyranoside were isolated fromAstragalus coluteocarpusBoiss. (Leguminosae) andAstragalus dissectusB. Fedtsch. et N. Ivanova, respectively. Cyclosiversigenin 5-O--L-rhamnopyranoside was shown to be an artifact forAstragalus coluteocarpus.Thus, the cyclosiversigenin 6-O--D-glucopyranoside that was isolated from certainAstragalusspecies is hypothesized also to be an artifact. Glycosylation of the 6 -hydroxyl group of cycloartanes by D-glucose and D-xylose, in contrast with other substituents, does not change the low-field position of the PMR signal of the 4-CH 3 group (1.65 2.01 ppm) that is caused by the influence of deuteropyridine directly on the 6 -hydroxyl. Obviously one of the hydroxyls of the -D-glucopyranoside or -D-xylopyranoside residues has the same effect in this instance.  相似文献   

4.
Conclusions The triterpene glycosides scabiosides D, E, F, and G have been isolated from the roots ofPatrinia scabiosofolia Fisch. et Link. It has been established that scabioside D is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)--D-xylopyranose, and scabioside E is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)-O--D-xylopyranosyl-(4 1)--L-rhamnopyranose.  相似文献   

5.
The crystal and molecular structure of [Au(C14H22N4)]Br has been determined. Monoclinic crystals, a=12.592(2), b=6.309(1), c=19.628(2) ; =98.00(1)°, V=1544.1(4) 3, Z=4, dcalc=2.251 g/cm3, space group C2/c. The structure consists of virtually planar centrosymmetric [Au(C14H22N4)]+ cations and Br- anions. The coordination sphere of the gold atom involves four nitrogen atoms of the ligands, forming a planar square. The Au–N bond lengths are equal (the mean length is 1.982(7) ). The C–C and C–N bonds inside the -diiminate rings are delocalized. The parameters of the -diiminate rings of the [Au(C14H22N4)]+ cation are compared with the parameters of the related complexes.  相似文献   

6.
Menthone on reduction with sodium dithionite,showed a good amount of mentholformation in the water/DMF system, withincreasing -cyclodextrin (-CD)concentration from 47.0% for 0.1 equivalent of-CD to 93.5% for 1 equivalentof -CD. Increasing hydroxypropyl--cyclodextrin(HP-CD) gave higher menthol/neomenthol (M/N) ratiosfrom 2.8 to 3.5. In the case of pulegone,increasing -CD showed an increase in the formationof menthols in thewater/DMF system from 13.3% for 0.1 equivalent of-CD to 78.1% for 1equivalent of -CD with greater proportions ofneomenthol and neoisomenthol.However, HP-CD which showed only marginalenhancement in the formationof menthol from menthone (32.1–41%), exhibiteda greater proportion of mentholformation in the case of pulegone (55.1%).However, the phase-transfer capabilityof HP-CD was not found to be significant.  相似文献   

7.
A low-background -counter and a simple direct method, based on total -counting, have been developed in order to estimate the concentration of uranium at the g/g level in ordinary rock samples. The method is a relative one; international standards have been used for calibration. Only 3 g of rock powder is needed. Combining this method with -spectrometry, direct determination of238U (independently of226Ra) becomes possible near the above concentration level.  相似文献   

8.
Conclusions The hydration of the triple bond in 17-ethynyltestosterone, its 17-acetate, and in 17-ethynyland-rost-5-ene-3,17-diol, its 3-acetate and the 3,17-diacetate by treatment with mercuric acetate in the presence of cationite Dowex-50 (H+ form) was accomplished, as a result of which some 20-ketols of the 17-isopregnane series were obtained.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 639–641, March, 1973.  相似文献   

9.
Zusammenfassung Die Synthese von 3, 16-Diacetoxy-5 -pregnan-20-on (VI) aus 3-Acetoxy-5 -pregn-16-en-20-on und eine verbesserte Darstellung von 3, 16-Diacetoxy-5 -pregnan-20-on (III) aus 3-Acetoxy-pregna-5, 16-dien-20-on werden beschrieben.  相似文献   

10.
Conclusions Syntheses are reported for ,-dithioalkyldivinyl ketones, which react with ammonia to give -amino--thioalkyldivinyl ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2414–2415, October, 1988.The authors thank A. M. Kachurin for assistance in taking the spectra.  相似文献   

11.
Four NiII chloro complexes were identified spectrophotometrically in aprotic media such as DMSO, DMF and propylene carbonate for the first time. An original multiwavelength numerical treatment, based on a Marquardt method, results in the determination of the individual electronic spectra of the mononuclear chloro complexes and of their stability constants, the values of which indicate the presence of rather weak complexes in DMSO and DMF, much stronger in the less solvating propylene carbonate solvent. The overall stability constants calculated for the NiII chloro complexes are: 1=52, 2=140, 3=160, 4=210 in DMSO, 1=60, 2=110, 3=900, 4=15000 in DMF, 1=1.6×109, 2=6.4×1015, 3=2.7×1021, 4= 5.1×1026 in PC.The solvent effect is discussed in terms of the quantitative results obtained from this spectrophotometric study and reveals that the stability of the complexes is an inverse function of the donor properties of the solvent. This result illustrates the general behavior of complex formation in dipolar aprotic solvents, i.e. the substitution of one solvent molecule in the inner coordination sphere by the ligand is easier if the solvation strength of the solvent is lower. The solvent effect is also described in terms of the variation of shifts of the calculated absorption maxima for the individual electronic spectra of the chloro complexes. This result is used to identify clearly at which step of coordination the octahedral configuration of the nickel ion changes to the tetrahedral configuration, by comparison with the well-known structural properties of these complexes in the solid state.  相似文献   

12.
Conformational analysis of inclusion complexes of sodium 3-hydroxy-2-naphthalenecarboxylate with -cyclodextrin and heptakis-(2,3,6-tri-o-methyl)--cyclodextrin in D2O was investigated by 1D and 2D 1HNMR measurements. The results show that part of the naphthyl group of sodium 3-hydroxy-2-naphthalenecarboxylate is situated in the 2,3-OH side of the -cyclodextrin cavity asymmetrically while the whole naphthyl group is included in the heptakis-(2,3,6-tri-o-methyl)--cyclodextrin cavity with the caboxylate and hydroxy group close to the 6-OCH3 group.  相似文献   

13.
Conclusions A synthesis was carried out for the 3-acetate of 16,23-oxido-21,24-dinorchol-5-en-3,17-diol-20-one and acetates of 16,23-oxido-21,24-dinorchol-5-en-3,17,20-triol, which are new polyhydrosteroids with an additional D-series E ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1156–1159, May, 1982.  相似文献   

14.
Rhodamine B-ethylenediamine--cyclodextrins (RhB--CDen) and rhodamine B--cyclodextrins (RhB--CD) can form inclusive complexes with many guest molecules, a reaction which can be used as a nucleic acid probe. In this paper, the most stable conformations of RhB--CDen and RhB--CD have been determined by fluorescence experiments and analyzed by molecular modeling simulation. The interaction between RhB--CDen and two guest molecules, 1-borneol and cyclohexanol, has also been investigated. The results showed that RhB--CDen has a stronger interaction with 1-borneol than with cyclohexanol. Borneol could push the three aromatic-rings of rhodamine B out of the CD cavity, while the cyclohexanol could not. The interactive sites of host and guest are also presented.  相似文献   

15.
The synergic extraction of La(III), Nd(III), Sm(III), Tb(III) and Lu(III) with 0.1M acetylacetone (Hacac) and 1,10-phenanthroline (phen) in benzene was studied. The adduct formation constant, s, for RE(acac)3 (phen) in benzene was determined. The s decreases with inceasing atomic number of RE(III). The s in different organic solvents can be predicted in connection with the activity coefficients of the solutes, and the validity of this prediction is confirmed by good agreement with the experimental values of s in carbon tetrachloride and heptane.  相似文献   

16.
The reaction of benzylidene-2-naphthylamine with ethyl -(3-ethyl)--oxopropionate under various conditions gave the ethyl ester of -(2-naphthylamino)benzyl--(3-pyridyl)--oxopropionic acid, 1-(3-pyridyl)-3 phenylbenzo[f]quinoline, ethyl ester of 1-(3-pyridyl)-3-phenylbenzo[f]quinoline-2-carboxylic acid, and N-(2-naphthyl)amide of -(3-pyridyl)--oxopropionic acid. The IR, UV, and mass spectra of the products were studied and the pathways for their formation were discussed.Institute of Physical Organic Chemistry, Belorussian Academy of Sciences, Minsk 220603. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 807–810, June, 1996. Original article submitted December 30, 1995.  相似文献   

17.
Semeik  A. S.  Berez  M. B.  Chernova  O. M.  Antina  E. V.  Syrbu  S. A.  Lyubimova  T. V.  Kutepov  A. M. 《Russian Chemical Bulletin》2003,52(8):1807-1813
New data on the spectral properties and solution enthalpies of unsymmetrically substituted 2-(alkyl-2-pyrrolylmethylidene)methylpyrrolium bromides (or ,-dipyrrylmethene hydrobromides), their ,-, ,-isomers, as well as their oxa and thia analogs, that is, 2-(2-furylmethylidene)- and 2-(2-thienylmethylidene)-3,4,5-trimethyl-1H-pyrrolium bromides, in solutions of organic solvents of different nature are presented. A decrease in the number of substituents, as well as replacement of the heteroatom (N) in one five-membered ring of the dipyrrylmetnehe by oxygen or sulfur atoms cause a monotonic hypsochromic shift of absorption bands in the electronic absorption spectrum and weakening of the chromophore properties of the compounds. The chromophore properties of isomers are weakened from the ,- to ,- and ,-dipyrrylmethenes. Main trends in the influence of structural factors on the specific features of thermooxidative destruction of the above-mentioned compounds were analyzed.  相似文献   

18.
The aim of our investigation was the development of carrier systems for an application of inert drugs in polyphasic photodynamic tumor therapy. As carrier systems, -cyclodextrin dimers linked at their primary and secondary faces by spacers of varying lengths were synthesized. Cyclodextrins are known to form stable inclusion complexes with porphyrinoïd photosensitizers. The influence of spacer length on the -cyclodextrin dimer inclusion complexes with porphyrinoïd photosensitizers was studied.  相似文献   

19.
Stereoregular polystyrene (PS) was prepared using various molarequivalents of -cyclodextrin (-CD) by polymerisingstyrene in the presence of -CD. Stereoregular (isotactic,atactic and syndiotactic) distributions of the preparedpolystyrene polymers were determined from terminal modelBernoullian statistics using 13C NMR data. Inclusioncomplexation of styrene by -cyclodextrin was detected byUV-Visible spectroscopy, which gave a binding constant value of31606 ± 3350 M-1 for the 1 : 1 complex. With anincrease in the styrene : -CD ratios, the proportionof syndiotactic polymers increased. The glass transitiontemperature (Tg) of the polymer also increased along withmelting temperature (Tm) at higher styrene : -CDratios. In addition, the molecular weight of the polymers prepareddecreased with increase in the -CD concentration.  相似文献   

20.
We report the first observation of confirmed 79Se activity in Savannah River Site high level fission product waste. 79Se was measured after a seven step chemical treatment to remove interfering activity from 137Cs, 90Sr, and plutonium at levels 105 times higher than the observed 79Se content and to remove 99Tc at levels 300 times higher than observed 79Se. 79Se was measured by liquid scintillation -decay counting after specific tests to eliminate uncertainties from possible contributions from 99Tc, 147Pm, 151Sm, 93Zr, or 241Pu, whose -decay spectra could appear similar to that of 79Se, and whose content would be expected at levels near or greater than 79Se.  相似文献   

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