Tungsten carbonyl complexes of Main Group IV organometallic sulfides

1983 ◽  
Vol 61 (6) ◽  
pp. 1096-1099 ◽  
Author(s):  
C. Robert Lucas
Keyword(s):  
Electron Density ◽  
Long Range ◽  
Spectroscopic Data ◽  
Spectroscopic Properties ◽  
Group Iv ◽  
Carbonyl Complexes ◽  
Multiple Bonds ◽  
Organic Systems ◽  
Tungsten Carbonyl ◽  
New Compounds

Vibrational spectroscopic data from the literature and from seven new compounds is treated by the methods of Cotton and Kraihanzel and of Graham. The results are interpreted as evidence that in (R3MSPh)W(CO)5 (R = Me, Ph: M = Si, Ge, Sn) there are W → S dπ–dπ and S → M pπ → dπ components to the bonding, the extent of the latter varying in the order Si > Ge > Sn. It is concluded that changes in the carbonyl stretching spectra reflect changes in electron density on sulfur. Thus, the carbonyl spectra are affected both by the electronegativity of groups bound to sulfur and by the extent of S → M π-bonding. The fact that changing M affects spectroscopic properties of a bond three atoms away represents long range transmission of effects via multiple bonds but in a manner quite unlike that in conjugated organic systems.

Synthese und Kristallstrukturen einiger Tetramethylstibonium-Hydrogendicarboxylate / Synthesis and Crystal Structures of Some Tetramethylstibonium Hydrogendicarboxylates

1982 ◽  
Vol 37 (11) ◽  
pp. 1393-1401 ◽  
Author(s):  
Beatrix Milewski-Mahrla ◽  
Hubert Schmidbaur
Keyword(s):  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Spectroscopic Data ◽  
Molar Ratio ◽  
Ionic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carboxylate Oxygen ◽  
Donor Acceptor ◽  
New Compounds

Reactions of pentamethylantimony (CH3)5Sb with carboxylic acids in the molar ratio 1:2 afford one equivalent of methane and essentially quantitative yields of crystalline tetramothylstibonium hydrogendicarboxylates. Six new compounds of this series have been synthesized using benzoic, o-phthalic, salicylic, 4-ethoxy-salicylic, oxalic, and malic acid, and characterized by analytical and spectroscopic data. An ionic structure with strong hydrogen bonds in the anionic components is proposed.The crystal structures of the hydrogen-dibenzoato (1), hydrogen-ortho-plithalato (2) and 4-ethoxy-hydrogen-salicylate (3) were determined by single crystal X-ray diffraction. The compounds can be described as having ionic lattices with some donor-acceptor inter­actions between the stibonium centers and the carboxylate oxygen atoms. The anions are characterized by strong hydrogen bonds O...H...O. Thus, the (CH3)4Sb-tetrahedron in 1 is distorted by two benzoate oxygon atoms (at 304(2) and 340(2) pin). The cation in 2 is largely undistorted and the anion has a hydrogenphthalate hydrogen bond of d(O...H...O) = 232 pm. The cation-anion contact in 3 is as short as d(Sb-O) = 289 pm rendering the Sb atom pentacoordinate.

scholarly journals Antibacterial and Cytotoxic Phenolic Polyketides from Two Marine-Derived Fungal Strains of Aspergillus unguis

2022 ◽  
Vol 15 (1) ◽  
pp. 74
Author(s):  
Cao Van Anh ◽  
Joo-Hee Kwon ◽  
Jong Soon Kang ◽  
Hwa-Sun Lee ◽  
Chang-Su Heo ◽  
...  
Keyword(s):  
Tumor Cell ◽  
Detailed Analysis ◽  
Cell Lines ◽  
Spectroscopic Data ◽  
Bacterial Activity ◽  
Tumor Cell Lines ◽  
Fungal Strains ◽  
Aspergillus Unguis ◽  
Ic50 Values ◽  
New Compounds

A chemical investigation on the EtOAc extracts from two marine-derived fungal strains of Aspergillus unguis resulted in the isolation of three previously undescribed phenolic polyketides including unguidepside C (1), aspersidone B (3), and agonodepside C (12), and their 14 known congeners. The structures of the new compounds were determined based on detailed analysis and comparison of their spectroscopic data with literature values, as well as Snatzke’s method. The new compounds (1, 3, and 12) displayed a significant anti-Gram-positive bacterial activity, with MIC values ranging from 5.3 to 22.1 µM. Additionally, the isolated compounds (1–11 and 13–16) were evaluated for their cytotoxicity against a panel of tumor cell lines. Most of them (except for 9) displayed cytotoxicity against all the tested cell lines, with IC50 values ranging from 2.5 to 46.9 µM.

scholarly journals α-Amylase and α-Glucosidase Inhibitory Activities of Chemical Constituents from Wedelia chinensis (Osbeck.) Merr. Leaves

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Nguyen Phuong Thao ◽  
Pham Thanh Binh ◽  
Nguyen Thi Luyen ◽  
Ta Manh Hung ◽  
Nguyen Hai Dang ◽  
...  
Keyword(s):  
Spectroscopic Data ◽  
Chemical Constituents ◽  
2D Nmr ◽  
Inhibitory Effects ◽  
Meoh Extract ◽  
Inhibitory Activities ◽  
Isolated Compound ◽  
New Compounds ◽  
Modified Mosher’S Method

As part of an ongoing search for new natural products from medicinal plants to treat type 2 diabetes, two new compounds, a megastigmane sesquiterpenoid sulfonic acid (1) and a new cyclohexylethanoid derivative (2), and seven related known compounds (3–9) were isolated from the leaves of Wedelia chinensis (Osbeck.) Merr. The structures of the compounds were conducted via interpretation of their spectroscopic data (1D and 2D NMR, IR, and MS), and the absolute configurations of compound 1 were determined by the modified Mosher’s method. The MeOH extract of W. chinensis was found to inhibit α-amylase and α-glucosidase inhibitory activities as well as by the compounds isolated from this extract. Furthermore, compound 7 showed the strongest effect with IC50 values of 112.8 ± 15.1 μg/mL (against α-amylase) and 785.9 ± 12.7 μg/mL (against α-glucosidase). Compounds 1, 8, and 9 showed moderate α-amylase and α-glucosidase inhibitory effects. Other compounds showed weak or did not show any effect on both enzymes. The results suggested that the antidiabetic properties from the leaves of W. chinensis are not simply a result of each isolated compound but are due to other components such as the accessibility of polyphenolic groups to α-amylase and α-glucosidase activities.

scholarly journals Noncovalent Bonds, Spectral and Thermal Properties of Substituted Thiazolo[2,3-b][1,3]thiazinium Triiodides

Crystals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 506 ◽  
Author(s):  
Irina Yushina ◽  
Natalya Tarasova ◽  
Dmitry Kim ◽  
Vladimir Sharutin ◽  
Ekaterina Bartashevich
Keyword(s):  
Electron Density ◽  
Noncovalent Interactions ◽  
Material Design ◽  
Spectroscopic Properties ◽  
Structural Features ◽  
Halogen Bonds ◽  
X Ray Diffraction ◽  
Raman Spectroscopic ◽  
Pairwise Interactions ◽  
Noncovalent Bonds

The interrelation between noncovalent bonds and physicochemical properties is in the spotlight due to the practical aspects in the field of crystalline material design. Such study requires a number of similar substances in order to reveal the effect of structural features on observed properties. For this reason, we analyzed a series of three substituted thiazolo[2,3-b][1,3]thiazinium triiodides synthesized by an iodocyclization reaction. They have been characterized with the use of X-ray diffraction, Raman spectroscopy, and thermal analysis. Various types of noncovalent interactions have been considered, and an S…I chalcogen bond type has been confirmed using the electronic criterion based on the calculated electron density and electrostatic potential. The involvement of triiodide anions in the I…I halogen and S…I chalcogen bonding is reflected in the Raman spectroscopic properties of the I–I bonds: identical bond lengths demonstrate different wave numbers of symmetric triiodide vibration and different values of electron density at bond critical points. Chalcogen and halogen bonds formed by the terminal iodine atom of triiodide anion and numerous cation…cation pairwise interactions can serve as one of the reasons for increased thermal stability and retention of iodine in the melt under heating.

scholarly journals Four New Minor Compounds from Seeds of Plantago asiatica

2016 ◽  
Vol 11 (5) ◽  
pp. 1934578X1601100
Author(s):  
Zhonghua Gao ◽  
Ling Zhang ◽  
Lingmei Kong ◽  
Yan Yang ◽  
Debing Pu ◽  
...  
Keyword(s):  
Spectroscopic Data ◽  
Indole Alkaloid ◽  
Comprehensive Analysis ◽  
Significant Activity ◽  
Plantago Asiatica ◽  
Minor Compounds ◽  
New Compounds

Four new compounds, a dibenzylbutane lignin, plasiaticine F (1), an acetylenic glycoside, plasiaticine G (2), an indole alkaloid, plasiaticine H (3), and an ionone derivative, plasiaticine I (4), were isolated from the seeds of Plantago asiatica. The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data. Compounds 1–3 were tested for their cytotoxicity, but lacked significant activity.

Reactions of organotin compounds. X. Reactions of tin hydrides with CF2=CFRe(CO)5, CF3CF=CFRe(CO)5, and some fluorinated alkenes

1969 ◽  
Vol 47 (20) ◽  
pp. 3753-3758 ◽  
Author(s):  
M. Akhtar ◽  
H. C. Clark
Keyword(s):  
Ultraviolet Irradiation ◽  
Spectroscopic Data ◽  
Organotin Compounds ◽  
Vinyl Fluoride ◽  
New Compounds ◽  
Derivatives Of

Trimethyltin hydride reacts with CF2=CFRe(CO)5 under ultraviolet irradiation to give new fluorovinyl derivatives of —Re(CO)5. Similar products were obtained using dimethyltin dihydride, but no reaction occurred between trimethyltin hydride and CF3CF=CFRe(CO)5. The reactions of trifluoroethylene, 1,1-difluoroethylene, and vinyl fluoride with trimethyltin hydride have been studied, thus completing the sequence of such reactions with fluorinated ethylenes. While both possible addition products were obtained with trifluoroethylene, and also from the corresponding reaction with perfluoropropene, 1,1-difluoroethylene gave only (CH3)3SnCH2CF2H, and with vinyl fluoride only trimethyltin fluoride and ethylene were isolated. Possible explanations are proposed and spectroscopic data for the new compounds are presented.

Tungsten carbonyl complexes with azoles

1972 ◽  
Vol 21 (3) ◽  
pp. 592-594
Author(s):  
A. D. Garnovskii ◽  
N. E. Kolobova ◽  
I. B. Zlotina ◽  
G. K. Mitina ◽  
K. N. Anisimov ◽  
...  
Keyword(s):  
Carbonyl Complexes ◽  
Tungsten Carbonyl
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