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31.
(1R,2R)-1,2-bis-(5-amino-1,3,4-thiadiazole-2-yl)ethane-1,2-diol (L) has been prepared by the reaction of thiosemicarbazide with (2R,3R)-(+)-tartaric
acid (I) and phosphorous oxychloride, and its complexes with Co(II), Ni(II) and Cu(II) have been obtained. The structures
of the ligand and its complexes have been established by i. r., 1H- and 13C-n.m.r. spectra, u.v.–vis–nir spectroscopy, elemental analyses, T.g.-D.t.a. and magnetic susceptibility measurements. 相似文献
32.
Several reactions of 2-naphthol with 2-alkyl-2-hydroxymethylaldehydes have been investigated. Novel synthesis of 14-(hydroxymethyl)alkyldibenzo[a,j]xanthenes and 3,3-dimethyl-4-(2-hydroxy-1-naphthyl)benzo[f]chroman has been realized. 相似文献
33.
Nuray Ulusoy Muammer Kiraz Ömer Küçükbasmacı 《Monatshefte für Chemie / Chemical Monthly》2002,133(10):1305-1315
Summary. New 4-alkyl/aryl-1-((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-3-thiosemicarbazides and 3-alkyl/aryl-2-(((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinones were synthesized from 6-(4-bromophenyl)-imidazo[2,1-b]thiazole-3-acetic acid hydrazide. Their structures were elucidated by elemental analyses and spectroscopic data. All compounds
were tested for antibacterial and antifungal activities. The antimicrobial activities of the compounds were assessed by the
microbroth dilution technique. The compounds were also evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv (ATCC 27294); they exhibited varying degrees of inhibition in the in vitro primary screening at 6.25 μg · cm−3. The most active compound was 3-(4-nitrophenyl)-2-(((6-(4-bromophenyl)-imidazo[2,1-b]thiazol-3-yl)-acetyl)-hydrazono)-4-thiazolidinone.
Corresponding author. E-mail: nurayulusoy@yahoo.com
Received December 10, 2001. Accepted (revised) March 1, 2002 相似文献
34.
H. Göktürk C. Eylem S. Hatipoĝlu H. N. Erten 《Journal of Radioanalytical and Nuclear Chemistry》1995,198(2):449-456
The sorption behavior of strontium and barium on kaolinite, bentonite and chlorite-illite mixed clay was studied by radioanalytical techniques using the batch method.90Sr (29.1 y) and133Ba (10.5 y) were used as radiotracers. Characterization of the solid matrices was done by FTIR and XRD spectrometries and specific surface area measurements. Synthetic groundwater was used as the aqueous phase. The variation of the distribution ratioR
d, as a function of metal ion loading was examined. The sorption isotherms were fitted to various isotherm models. The sorption energies were calculated to be in the range of 8–10 kJ/mol suggesting an ion exchange type of sorption mechanism. In detailed experiments, chlorite-illite mixed clay was first presaturated with K+, Sr2+, Ca2+ and Al3+ ions, respectively, prior to sorption studies with Ba2+ ions. The results of Ca2+ pretreated chlorite-illite were very similar to those of natural chlorite-illite, suggesting that the Ba2+ ion exchanges primarily with the Ca2+ ion on the clay minerals. 相似文献
35.
Naki Çolak Yılmaz Yıldırır Mustafa Kavutcu Nilhan Nurlu 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1283-1287
Summary. Methotrexate (MTX) is a folate antagonist used in treatment of several chronic inflammatory and neoplastic conditions. In this study, new MTX-like compounds that may-be potential anticancer agents were synthesized and their structures were determined by IR, UV, GC-MS,
1H NMR, and 13C NMR spectra. Also, in this study, a series structurally related to MTX or folate analogous compounds were evaluated whether they have inhibitory properties on the dihydrofolate reductase activity
(DHFR). 相似文献
36.
The ligand has been
prepared from ω-chloroisonitrosoacetophenone and 1,4-phenylenediamine
in the presence of NaHCO3. The ligand have a C=O group
and an –NH–R group adjacent to the oxime group. The Ni(II), Cu(II)
and Co(II) complexes of the synthesized ligand were prepared and their structures
were identified using FTIR, UV-Vis spectral data, elemental analysis, thermal
analysis and magnetic moment measurements. The metal-ligand ratios were found
to be 3:2. The ligands were found to coordinate to the metal ions via the
oxime nitrogen, oxime oxygen, one of the carbonyl group and amide nitrogen
atoms. Thermal analyses data reveals that the water in the complexes was found
to be non-coordinated to the metal ions. In the trinuclear structures, the
metals have the tetrahedral environments. 相似文献
37.
Hakki İsmail Erdoğan 《Journal of Geometry》1991,40(1-2):47-59
In this paper, the problem of determining the pencils of circles which form a hexagonal n-web in E2, is completely solved. It is well-known that n pencils of circles orthogonal to a fixed circle form a hexagonal n-web. Therefore, the main problem is the determination of all circle pencils which form a hexagonal n-web and which do not cut a fixed circle orthogonally. In this connection the following results have been obtained: The number of hexagonal 4-webs is six, whereas the number of hexagonal 5-webs is two.Finally, after having proved that the number of hexagonal 6-webs is one, it is shown that, for n7, there exist no circle pencils forming a hexagonal n-web without being orthogonal to a fixed circle. 相似文献
38.
Uzun O Sanyal A Nakade H Thibault RJ Rotello VM 《Journal of the American Chemical Society》2004,126(45):14773-14777
Polystyrene functionalized with diamidopyridine (DAP) recognition units self-assembles in nonpolar media to form thermally reversible micrometer-scale spherical aggregates. The size and the thermal stability of these microspheres can be controlled by the molecular weight of the polymer. The addition of thymine-functionalized polymer to these self-assembled microspheres converted them into vesicular aggregates with a controlled size. The morphology change was reversible: the addition of DAP-functionalized polymer converted the vesicles back to microspheres. 相似文献
39.
A new alcohol soluble functionalized vic-dioxime, bis-[(1-hydroxyhexyl)-(8,9-hydroxyimino)-7,10-dithiahexacosane (LH2), and its alcohol-soluble mono and dinuclear complexes (NiII, CuII, CoII, MnII, PdII and UO
2
II
) have been prepared from 6-mercapto-1-hexanol and (E,E)-dichloroglyoxime under high dilution basic conditions. Reactive polyalcohol moieties appended at the periphery of the oxime
containing two different heteroatoms (S-, O-), serve as a weak exocyclic binding sites for PdII and AgI metal ions and also provide solubility for the vic-dioxime complexes in low molecular-weight alcohols. Both mono-nuclear (LH)2M and homodinuclear (LH)2(UO2)2(OH)2 and heterotrinuclear (LH)2MM
2
′
Xn, where M = CoII M′ = PdII, X = Cl−, n = 4 and AgI X = NO
3
−
, n = 2) complexes have been obtained with a 1:2, 2:2, 3:2 metal/ligand ratio, respectively. Electronic spectra of the modified
vic-dioximes exhibit monitorable changes in UV. All mono and dinuclear-complexes are soluble in common organic solvents. The
elemental analysis, 1H-n.m.r, i.r., u.v–vis, and f.a.b.–m.s data and by cyclic and differential pulse voltammetry measurements are presented. 相似文献
40.
Refiye Beyza Ozturk Gokhan Zengin Kouadio Ibrahime Sinan Domenico Montesano Dimitrina Zheleva-Dimitrova Reneta Gevrenova Abdullahi Ibrahim Uba Uur aklcolu Alevcan Kaplan Sharmeen Jugreet Stefano DallAcqua Mohamad Fawzi Mahomoodally 《Molecules (Basel, Switzerland)》2022,27(15)
The bioactive content, antioxidant properties, and enzyme inhibition properties of extracts of Alcea fasciculiflora from Turkey prepared with different solvents (water, methanol, ethyl acetate) and extraction methods (maceration, soxhlet, homogenizer assisted extraction, and ultrasound assisted extraction) were examined in this study. UHPLC-HRMS analysis detected or annotated a total of 50 compounds in A. fasciculiflora extracts, including 18 hydroxybenzoic and hydroxycinnamic acids, 7 Hexaric acids, 7 Coumarins, 15 Flavonoids, and 3 hydroxycinnamic acid amides. The extracts had phenolic and flavonoid levels ranging from 14.25 to 24.87 mg GAE/g and 1.68 to 25.26 mg RE/g, respectively, in the analysis. Both DPPH and ABTS tests revealed radical scavenging capabilities (between 2.63 and 35.33 mg TE/g and between 13.46 and 76.27 mg TE/g, respectively). The extracts had reducing properties (CUPRAC: 40.38–78 TE/g and FRAP: 17.51–42.58 TE/g). The extracts showed metal chelating activity (18.28–46.71 mg EDTAE/g) as well as total antioxidant capacity (phosphomolybdenum test) (0.90–2.12 mmol TE/g). DPPH, ABTS, FRAP, and metal chelating tests indicated the water extracts to be the best antioxidants, while the ethyl acetate extracts had the highest overall antioxidant capacity regardless of the extraction technique. Furthermore, anti-acetylcholinesterase activity was identified in all extracts (0.17–2.80 mg GALAE/g). The water extracts and the ultrasound-assisted ethyl acetate extract were inert against butyrylcholinesterase, but the other extracts showed anti-butyrylcholinesterase activity (1.17–5.80 mg GALAE/g). Tyrosine inhibitory action was identified in all extracts (1.79–58.93 mg KAE/g), with the most effective methanolic extracts. Only the ethyl acetate and methanolic extracts produced by maceration and homogenizer aided extraction showed glucosidase inhibition (0.11–1.11 mmol ACAE/g). These findings showed the overall bioactivity of the different extracts of A. fasciculiflora and provided an overview of the combination of solvent type and extraction method that could yield bioactive profile and pharmacological properties of interest and hence, could be a useful reference for future studies on this species. 相似文献