Bleispezies PbX und PbX2 als Brückenliganden in übergangsmetallorganisch geschützten Koordinationsverbindungen/ Leadspecies PbX and PbX2 as Bridging Ligands in Organometallic Protected Coordination Compounds

2002 ◽  
Vol 57 (1) ◽  
pp. 25-42 ◽  
Author(s):  
Peter Rutsch ◽  
Gottfried Huttner
Keyword(s):  
Coordination Compounds ◽  
Dynamic Behaviour ◽  
Disodium Salt ◽  
3D Nmr ◽  
Spectroscopic Techniques ◽  
The Novel ◽  
Bridging Ligands ◽  
X Ray ◽  
Nmr Data ◽  
First Time

The disodium salt Na2[{(CO)5Cr}2Pb(NO3)2], Na2·1, which contains a lead center in a (4+2) coordination mode, reacts with tetraphenylphosphonium halides [Ph4P]X to give the tetrahedral compounds [Ph4P]2[{(CO)5Cr}2PbX2] (X = Cl: 2a; X = Br: 2b; X = I: 2c). Substitution of the nitrate groups of Na2·1 by alcoxides leads to binuclear compounds of the type [{(CO)5Crg2Pb(μ2-OR)2Pb{Cr(CO)5}2]2- (R = Et: 3a; R = n -Pr: 3b; R = i-Pr: 3c; R = Allyl: 3d). NMR experiments show that these dimeric compounds are in equilibrium with the monomeric species [{(CO)5Cr}2PbR]- .Trialkylphosphanes react with Na2·1 to give the neutral phosphane complexes [{(CO)5Cr}2Pb(PR3)2] (R=Me: 4a; R=Et: 4b; R = n-Bu: 4c), which show dynamic behaviour in solution. All of the novel compounds have been characterized by X-ray analysis, as well as by the usual analytic and spectroscopic techniques. 207Pb-NMR data of Cr(CO)5- bound lead species are reported for the first time.

Crystal structure and enantiomeric layer disorder of a copper(I) nitrate π-coordination compound

2021 ◽  
Vol 77 (2) ◽  
Author(s):  
Dorota A. Kowalska ◽  
Vasyl Kinzhybalo ◽  
Yuriy I. Slyvka ◽  
Marek Wołcyrz
Keyword(s):  
Coordination Compound ◽  
Local Structure ◽  
Diffuse Scattering ◽  
Weak Interactions ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Solution ◽  
First Time ◽  
Layer Disorder

The novel π-coordination compound [CuI(m-dmphast)NO3], where m-dmphast = 5-(allylthio)-1-(3,5-dimethylphenyl)-1H-tetrazole, is characterized using single-crystal X-ray diffraction and crystallizes in a noncentrosymmetric space group. Additionally, for the first time in this group of materials, the streaks of X-ray diffuse scattering in the reciprocal space sections were observed and described. This gave the possibility for a deeper insight into the local structure of the title compound. The conjecture about the origin of diffuse scattering was derived from average structure solution. It was then confirmed using the local structure modelling. The extended [Cu(m-dmphast)NO3]∞ chains, connected by weak interactions, produce layers which can exist in two enantiomeric forms, one of which predominates.

Isolation of Bioactive Compounds from Aspergillus terreus

2004 ◽  
Vol 59 (3) ◽  
pp. 324-328 ◽  
Author(s):  
Muhammad I. Choudhary ◽  
Syed G. Musharraf ◽  
Talat Mukhmoor ◽  
Farzana Shaheen ◽  
Shamsher Ali ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
13C Nmr ◽  
Culture Medium ◽  
Aspergillus Terreus ◽  
Ethyl Acetate Extract ◽  
Microsporum Canis ◽  
Spectroscopic Techniques ◽  
Significant Activity ◽  
Nmr Data ◽  
First Time

A new metabolite, 6-(4’-hydroxy-2’-methyl phenoxy)-(-)-(3R)-mellein (1) was isolated from the ethyl acetate extract of Aspergillus terreus culture medium along with three known isocoumarin derivatives, (-)-(3R)-6-methoxymellein (2), (-)-(3R)-6,7-dimethoxymellein (Kigelin) (3) and (3R, 4R)-6,7-dimethoxy-4-hydroxymellein (4). Metabolites 1 and 4 showed significant activity against human pathogenic dermatophytes, Microsporum canis and Trichophyton longifusus. Metabolite 1 also exhibited potent antioxidant activity. The structures of metabolites were characterized on the basis of spectroscopic techniques. 13C NMR data of metabolites 2 - 4 are also being reported for the first time

Fabrication of boron carbonitride (BCN) nanotubes and giant fullerene cages

2010 ◽  
Vol 88 (12) ◽  
pp. 1256-1261 ◽  
Author(s):  
Guifang Sun ◽  
Faming Gao ◽  
Li Hou
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
The Novel ◽  
X Ray Diffraction ◽  
Boron Carbonitride ◽  
X Ray ◽  
Transmission Electron ◽  
New Form ◽  
First Time ◽  
Electron Energy Loss

Boron carbonitride (BCN) nanotubes have been successfully prepared using NH4Cl, KBH4, and ZnBr2 as the reactants at 480 °C for 12 h by a new benzene-thermal approach in a N2 atmosphere. As its by-product, a new form of carbon regular hexagonal nanocages are observed. The samples are characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), transmission electron diffraction (TED), electron energy loss spectroscopy (EELS), and high-resolution transmission electron microscopy (HRTEM). The prepared nanotubes have uniform outer diameters in the range of 150 to 500 nm and a length of up to several micrometerss. The novel carbon hexagonal nanocages have a typical size ranging from 100 nm to 1.5 µm, which could be the giant fullerene cages of [Formula: see text] (N = 17∼148). So, high fullerenes are observed for the first time. The influences of reaction temperature and ZnBr2 on products and the formation mechanism of BCN nanotubes are discussed.

scholarly journals Methylated Flavonols from Amomum koenigii J.F.Gmel. and Their Antimicrobial and Antioxidant Activities

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Minh Giang Phan ◽  
Thi Viet Huong Do ◽  
Quoc Binh Nguyen
Keyword(s):  
Escherichia Coli ◽  
Antioxidant Activities ◽  
Biological Activities ◽  
Spectroscopic Techniques ◽  
Special Group ◽  
X Ray ◽  
Rp Hplc ◽  
Dpph Scavenging ◽  
First Time ◽  
Antimicrobial Assay

Methylated flavonols form a special group with modulating biological activities in comparison with kaempferol and quercetin. The present study isolated ten compounds including two kaempferol methyl ethers: 5-hydroxy-3,7,4′-trimethoxyflavone (1), 3-hydroxy-5,7,4′-trimethoxyflavone (6); four quercetin methyl ethers: retusin (5-hydroxy-3,7,3′,4′-tetramethoxyflavone) (4), 3,5-dihydroxy-7,3′,4′-trimethoxyflavone (5), 3,4′-dihydroxy-5,7,3′-trimethoxyflavone (7), and 3,5,7,3′,4′-pentamethoxyflavone (9); β-sitosterol (2); 5-hydroxy-1-(4′-hydroxyphenyl)eicosan-3-one (3); p-hydroquinone (8); and vanillic acid (10) from the rhizomes and fruit of Amomum koenigii J.F.Gmel. (Zingiberaceae). Their structures were determined by MS, NMR, and X-ray spectroscopic techniques. Among the methylated flavonols, 1, 4–7, and 9 were isolated for the first time from the rhizomes, while 1, 4, and 5 were isolated from the fruit. Compounds 2, 3, 7, 8, and 10 were reported for the first time from the species. Three main methylated flavonols 1, 4, and 5 were quantitatively analyzed in the rhizomes of A. koenigii by RP-HPLC-DAD; their contents were determined to be 1.81% (1), 1.38% (4), and 1.76% (5). The antimicrobial assay against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger, Fusarium oxysporum, Candida albicans, and Saccharomyces cerevisiae and antioxidant DPPH scavenging test were performed for the isolated methylated flavonols.

Electrochemical and spectral properties of tris[tetra(15-crown-5)phthalocyaninato]dilutetium(III)

2005 ◽  
Vol 09 (01) ◽  
pp. 1-6 ◽  
Author(s):  
Igor V. Zhukov ◽  
Lyudmila A. Lapkina ◽  
Yuliya G. Gorbunova ◽  
Vladimir E. Larchenko ◽  
Aslan Yu. Tsivadze
Keyword(s):  
Cyclic Voltammetry ◽  
Spectral Properties ◽  
Redox Properties ◽  
X Ray ◽  
H Nmr ◽  
Nmr Data ◽  
Physicochemical Studies ◽  
First Time

Tris[tetra(15-crown-5)phthalocyaninato]dilutetium(III) ( R 4 Pc )3 Lu 2, whose structure had been confirmed earlier by X-ray analysis, was further examined by physicochemical studies. The redox properties of this complex were investigated by cyclic voltammetry. The spectroelectrochemical study of this compound has been performed for the first time. Based on the results obtained and analysis of literature data, an electrochemical criterion related to double- and triple-decker structure of lanthanide phthalocyanines has been proposed. IR and 1 H NMR data are also reported.

Coordination Compounds of Lanthanide Nitrates with Dimorpholido-N-trichloroacetylphosphorylamide. The Structure of Di(dimorpholido-N-trichloroacetylphosphorylamide)- diaqua Neodymium(III)trinitrate

2000 ◽  
Vol 55 (3-4) ◽  
pp. 262-268 ◽  
Author(s):  
Vladimir A. Ovchynnikov ◽  
Taras P. Timoshenko ◽  
Vladimir M. Amirkhanov ◽  
Joachim Sieler ◽  
Viktor V. Skopenko
Keyword(s):  
Molecular Structure ◽  
Coordination Compounds ◽  
Methanol Solution ◽  
Acetone Solution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nmr Data ◽  
Weak Electrolytes ◽  
Phosphoryl Oxygen ◽  
Lanthanide Nitrates

Abstract Lanthanide, Carbacylamidophosphate The coordination compounds of the general formula Ln(NO3)3(HL)2(H2O)2 H2O , where Ln = La, Ce -Nd, Sm -Dy, HL = CCl3C(O)NHP(O)[N(CH2CH2)2O]2, dimorpholido-N-tri-chloroacetylphosphorylamide, have been synthesized. The complexes were studied by IR, 1H and 31P NMR and UV-VIS absorption spectroscopies. X-ray diffraction analyses indicate that all synthesized compounds are isostructural. The crystal structure of Nd(NO3)3(HL)2(H2O)2 H2O was solved (monoclinic, a = 11.0467(3), b = 15.9080(5), c = 24.1921(7) Å, β = 96.4080(10)°, space group P21/n, V = 4224.7(2) Å3, Z = 4, R = 0.049, wR = 0.0915). The complex has a molecular structure. The monodentate neutral phosphorictriamide ligands are coordinated to the metal atom via the phosphoryl oxygen atom. The coordination polyhedron of Nd is a sphenocorona; C.N. = 10(60[NO3-], 20[HL], 20[H2O]). It was shown that these compounds in methanol solution are 1:1 electrolytes, and in acetone solution weak electrolytes. According to NMR data in acetone solution the complexes of the lanthanides with the ligand {HL} have axial symmetry.

scholarly journals Sicilian Byzantine Icons through the Use of Non-Invasive Imaging Techniques and Optical Spectroscopy: The Case of the Madonna dell’Elemosina

Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7595
Author(s):  
Francesco Armetta ◽  
Gabriella Chirco ◽  
Fabrizio Lo Celso ◽  
Veronica Ciaramitaro ◽  
Eugenio Caponetti ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Spectroscopic Techniques ◽  
Eastern European ◽  
X Ray ◽  
Non Invasive ◽  
Byzantine Art ◽  
Byzantine Icons ◽  
Foreign Materials ◽  
Infrared Reflectography ◽  
First Time

The iconographic heritage is one of the treasures of Byzantine art that have enriched the south of Italy, and Sicily in particular, since the early 16th century. In this work, the investigations of a Sicilian Icon of Greek-Byzantine origin, the Madonna dell’Elemosina, is reported for the first time. The study was carried out using mainly non-invasive imaging techniques (photography in reflectance and grazing visible light, UV fluorescence, infrared reflectography, radiography, and computed tomography) and spectroscopic techniques (X-ray fluorescence and infrared spectroscopy). The identification of the constituent materials provides a decisive contribution to the correct historical and artistic placement of the Icon, a treasure of the Eastern European historical community in Sicily. Some hidden details have also been highlighted. Most importantly, the information obtained enables us to define its conservation state, the presence of foreign materials, and to direct its protection and restoration.

A novel method for determining the X-ray beam angulation of the supraspinatus outlet view

2021 ◽  
pp. 028418512110438
Author(s):  
Xiaoli Zheng ◽  
Jingying Hu ◽  
Jian Xu ◽  
Zhen Wang ◽  
Zhenyu Shu ◽  
...  
Keyword(s):  
Success Rate ◽  
Pearson Correlation ◽  
Three Dimensional ◽  
The Novel ◽  
Ct Reconstruction ◽  
Beam Angle ◽  
X Ray ◽  
Horizontal Angle ◽  
Novel Method ◽  
First Time

Background Rapid and accurate quantification of the supraspinatus outlet view (SOV) is a clinical challenge. Purpose To quantify the X-ray beam angle of the SOV using the horizontal angle of the subscapular spine line (SSSL) and to further verify the feasibility of this method. Material and Methods A total of 119 patients who underwent shoulder computed tomography (CT) examination were enrolled in the retrospective study. Three-dimensional (3D) CT reconstruction was performed and manually adjusted to provide the position similar to SOV. The rotation angle of the 3D image along the long axis of the human body (marked as β) was obtained. The horizontal angle of SSSL (marked as α) was measured on the anteroposterior localizer image of shoulder CT. Pearson correlation and linear regression correlation analysis were performed. In addition, the first-time success rate between the experience-based group and the measurement-based group were compared to verify the novel method. Results We found a linear correlation between α and β (r = 0.962; P = 0.000). There was no significant correlation between the experience-based group and the measurement-based group in terms of age ( P = 0.500), sex ( P = 0.397), and side ( P = 0.710), but there was a significant statistical difference in the first success rate between the two validation groups (χ2 = 5.808a, P = 0.016). Conclusion This novel quantitative measurement method for determining the X-ray beam angle of SOV using the horizontal angle of SSSL is feasible.

scholarly journals Bufadienolides from the Venom of Bufo Bufo gargarizans and Their Enzyme Inhibition Activities and Brine Shrimp Lethality

2018 ◽  
Vol 13 (7) ◽  
pp. 1934578X1801300 ◽  
Author(s):  
Jian Xiao ◽  
Xiang Zhao ◽  
Wan-Tong Zhong ◽  
Fu-Rong Jiao ◽  
Xiao-Ling Wang ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Brine Shrimp ◽  
Bufo Bufo ◽  
Positive Control ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Nmr Data ◽  
Bufo Gargarizans ◽  
First Time ◽  
Potent Inhibitory Activity

A new bufadienolide named dyscinobufotalin (1), along with twenty known bufadienolides (2–21) were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated by spectroscopic analysis. The absolute configuration of the new natural product 2 was determined by X-ray single crystal diffraction and the complete NMR data for 3 was delivered for the first time. Both compounds 4 and 8 showed comparable α-glucosidase inhibitory activity (IC50 values of 0.25 and 0.26 μM, respectively) to the positive control acarbose (IC50 value of 0.42 μM), and 5 displayed potent inhibitory activity on acetylcholinesterase with an IC50 value of 0.12 μM. Moreover, 5, 8 and 13 presented moderate toxicity against brine shrimp.

Konfigurations-Bestimmung von Isomeren des Methyl 4-O-Acetyl-2.3-O-(1-phenylethyliden)-α-L-rhamnopyranosides/ The Configuration of Isomeres of Methyl 4-O-Acetyl-2,3-O-(1-phenylethylidene)-α-L-rhamnopyranoside

1981 ◽  
Vol 36 (8) ◽  
pp. 997-999 ◽  
Author(s):  
Hermann Lotter ◽  
András Lipták
Keyword(s):  
Crystalline State ◽  
X Ray ◽  
Nmr Data ◽  
First Time

AbstractThe diastereomeric 2,3-O-[2-phenyl-2-methyl-1,3 dioxalanes] of methyl-α-L-rhamno-pyranosides were synthesised for the first time. The stereochemical characterisation was carried out by X-ray analysis. Evaluation of the X-ray data and comparison with NMR data indicated that the same configuration exists in the crystalline state as in solution.

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