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Molecules (Basel, Switzerland) Mar 2024A convenient protocol for the synthesis of 25,26,27-tribenzoyl-28-[(()-1-diphenylphos- phanyl-propan-2-yl)oxy]-calix[4]arene via stereospecific methylation on Evans'...
A convenient protocol for the synthesis of 25,26,27-tribenzoyl-28-[(()-1-diphenylphos- phanyl-propan-2-yl)oxy]-calix[4]arene via stereospecific methylation on Evans' oxazolidinone moiety was reported. According to the C NMR analysis of this phosphine, the calix[4]arene skeleton adopted a 1,3-alternate conformation. The latter conformation of the macrocycle and the ()-chirality of the carbon atom bearing the methyl substituent were confirmed by a single-crystal X-ray diffraction study. After coordination of the phosphinated ligand to the dimeric [RuCl(-cymene)] organometallic precursor, the resulting arene-ruthenium complex was tested in the asymmetric reduction of acetophenone and alcohol was obtained with modest enantiomeric excess.
PubMed: 38474667
DOI: 10.3390/molecules29051156 -
Molecules (Basel, Switzerland) Mar 2024A wide range of platinum(0)-η-()-1,2-ditosylethene complexes bearing isocyanide, phosphine and -heterocyclic carbene ancillary ligands have been prepared with high...
Platinum(0)-η-1,2-()ditosylethene Complexes Bearing Phosphine, Isocyanide and -Heterocyclic Carbene Ligands: Synthesis and Cytotoxicity towards Ovarian and Breast Cancer Cells.
A wide range of platinum(0)-η-()-1,2-ditosylethene complexes bearing isocyanide, phosphine and -heterocyclic carbene ancillary ligands have been prepared with high yields and selectivity. All the novel products underwent thorough characterization using spectroscopic techniques, including NMR and FT-IR analyses. Additionally, for some compounds, the solid-state structures were elucidated through X-ray diffractometry. The synthesized complexes were successively evaluated for their potential as anticancer agents against two ovarian cancer cell lines (A2780 and A2780) and one breast cancer cell line (MDA-MB-231). The majority of the compounds displayed promising cytotoxicity within the micromolar range against A2780 and MDA-MB-231 cells, with IC values comparable to or even surpassing those of cisplatin. However, only a subset of compounds was cytotoxic against cisplatin-resistant cancer cells (A2780). Furthermore, the assessment of antiproliferative activity on MRC-5 normal cells revealed certain compounds to exhibit in vitro selectivity. Notably, complexes , and showed low cytotoxicity towards normal cells (IC > 100 µM) while concurrently displaying potent cytotoxicity against cancer cells.
Topics: Female; Humans; Cisplatin; Platinum; Cell Line, Tumor; Cyanides; Breast Neoplasms; Spectroscopy, Fourier Transform Infrared; Ovarian Neoplasms; Coordination Complexes; Antineoplastic Agents; Ligands; Methane; Phosphines
PubMed: 38474631
DOI: 10.3390/molecules29051119 -
Scientific Reports Mar 2024Herein, core-shell magnetic nanoparticles are modified with imidazolium-tagged phosphine and propylene glycol moieties and used for the stabilization of bimetallic AuCu...
Herein, core-shell magnetic nanoparticles are modified with imidazolium-tagged phosphine and propylene glycol moieties and used for the stabilization of bimetallic AuCu nanoparticles. The structure and morphology of the prepared material are identified with SEM, TEM, XRD, XPS, atomic absorption spectroscopy, Fourier translation infrared spectroscopy, and a vibrating sample magnetometer. This hydrophilic magnetic bimetallic catalyst is applied in the reduction of toxic nitroarenes and reductive degradation of hazardous organic dyes such as methyl orange (MO), methyl red (MR), and rhodamine B (RhB), as well as in the degradation of tetracycline (TC). This magnetic AuCu catalyst indicated superior activity in all three mentioned reactions in comparison with its single metal Au and Cu analogs. This catalyst is recycled for 17 consecutive runs in the reduction of 4-nitrophenol to 4-aminophenol without a significant decrease in catalytic activity and recycled catalyst is characterized.
PubMed: 38462664
DOI: 10.1038/s41598-024-56559-4 -
Scientific Reports Mar 2024In these studies, we designed and investigated the potential anticancer activity of five iron(II) cyclopentadienyl complexes bearing different phosphine and phosphite...
In these studies, we designed and investigated the potential anticancer activity of five iron(II) cyclopentadienyl complexes bearing different phosphine and phosphite ligands. All complexes were characterized with spectroscopic analysis viz. NMR, FT-IR, ESI-MS, UV-Vis, fluorescence, XRD (for four complexes) and elemental analyses. For biological studies, we used three types of cells-normal peripheral blood mononuclear (PBM) cells, leukemic HL-60 cells and non-small-cell lung cancer A549 cells. We evaluated cell viability and DNA damage after cell incubation with these complexes. We observed that all iron(II) complexes were more cytotoxic for HL-60 cells than for A549 cells. The complex CpFe(CO)(P(OPh))(η-N-maleimidato) 3b was the most cytotoxic with IC = 9.09 µM in HL-60 cells, IC = 19.16 µM in A549 and IC = 5.80 µM in PBM cells. The complex CpFe(CO)(P(Fu))(η-N-maleimidato) 2b was cytotoxic only for both cancer cell lines, with IC = 10.03 µM in HL-60 cells and IC = 73.54 µM in A549 cells. We also found the genotoxic potential of the complex 2b in both types of cancer cells. However, the complex CpFe(CO)(η-N-maleimidato) 1 which we studied previously, was much more genotoxic than complex 2b, especially for A549 cells. The plasmid relaxation assay showed that iron(II) complexes do not induce strand breaks in fully paired ds-DNA. The DNA titration experiment showed no intercalation of complex 2b into DNA. Molecular docking revealed however that complexes CpFe(CO)(PPh) (η-N-maleimidato) 2a, 2b, 3b and CpFe(CO)(P(OiPr))(η-N-maleimidato) 3c have the greatest potential to bind to mismatched DNA. Our studies demonstrated that the iron(II) complex 1 and 2b are the most interesting compounds in terms of selective cytotoxic action against cancer cells. However, the cellular mechanism of their anticancer activity requires further research.
Topics: Humans; Molecular Docking Simulation; Phosphites; Coordination Complexes; Iron; Carcinoma, Non-Small-Cell Lung; Leukocytes, Mononuclear; Spectroscopy, Fourier Transform Infrared; Lung Neoplasms; DNA; Maleimides; Ferrous Compounds; Antineoplastic Agents; Ligands; Cell Line, Tumor; Phosphines
PubMed: 38454122
DOI: 10.1038/s41598-024-56339-0 -
Journal of Chromatography. B,... Apr 2024This study aimed to prove the validity of a mixture of chemicals, including salts, small organic molecules, mucin, and α-amylase, as saliva surrogate ("artificial...
This study aimed to prove the validity of a mixture of chemicals, including salts, small organic molecules, mucin, and α-amylase, as saliva surrogate ("artificial saliva") for assessing leakage of methacrylate monomers and other constituents from dental materials. To achieve this, we developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA), diurethane dimethacrylate (UDMA), bisphenol A glycerolate dimethacrylate (BisGMA), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), bisphenol A (BPA), and five homologues of ethoxylated bisphenol A dimethacrylate (BisEMA EO2-6) in unstimulated and artificial saliva, and compared their concentrations in the two saliva media following either spiking with a mixture of the compounds or incubation of test specimens of printed biomaterials. Test specimens were immersed in unstimulated/artificial saliva, incubated at 37 °C for 24 h, and saliva aliquots were extracted with methanol and subsequently analyzed by LC-MS/MS. The method was validated with regard to matrix effects, linearity, selectivity, lower limits of quantification (LLOQ), precision, bias and combined measurement uncertainty (u'). The performance characteristics of the method were comparable for unstimulated and artificial saliva samples. The combined u' for individual chemicals at a concentration of 10 × LLOQ were within the range of 5.3-14 % for unstimulated saliva and 6.9-16 % for artificial saliva, except for the BisEMA homologues. Combined u' for the latter were 27-74 % in unstimulated saliva, and 27-79 % in artificial saliva. There was no detectable release of BPA from the test specimens, and the TPO concentrations were mainly below the LLOQ. TEGDMA and UDMA were detected in the highest quantities, and at comparable concentrations in the unstimulated and artificial saliva. For all BisEMA homologues, the release was higher in unstimulated saliva than in artificial saliva. The study showed that the artificial saliva model can be a suitable replacement for native saliva, but might underestimate leakage of more lipophilic methacrylates.
Topics: Humans; Saliva; Chromatography, Liquid; Composite Resins; Saliva, Artificial; Tandem Mass Spectrometry; Methacrylates; Polymethacrylic Acids; Polyethylene Glycols; Materials Testing; Benzhydryl Compounds; Phenols
PubMed: 38452631
DOI: 10.1016/j.jchromb.2024.124073 -
RSC Advances Feb 2024The transition metal-mediated dimerisation of terminal alkynes is an attractive and atom-economic method for preparing conjugated 1,3-enynes. Using a phosphine-based...
The transition metal-mediated dimerisation of terminal alkynes is an attractive and atom-economic method for preparing conjugated 1,3-enynes. Using a phosphine-based macrocyclic pincer ligand, we demonstrate how this transformation can be extended to the synthesis of novel, hydrocarbon-based interlocked molecules: a rotaxane by 'active' metal template synthesis and a catenane by sequential 'active' and 'passive' metal template procedures.
PubMed: 38444978
DOI: 10.1039/d4ra00566j -
Nature Communications Mar 2024The development of stable and efficient ligands is of vital significance to enhance the catalytic performance of carbonylation reactions of alkenes. Herein, an...
The development of stable and efficient ligands is of vital significance to enhance the catalytic performance of carbonylation reactions of alkenes. Herein, an aryldiphosphine ligand (L11) bearing the [PhP(ortho-CH)]CH skeleton is reported for palladium-catalyzed regioselective carbonylation of alkenes. Compared with the industrially successful Pd/1,2-bis(di-tert-butylphosphinomethyl)benzene catalyst, catalytic efficiency catalyzed by Pd/L11 on methoxycarbonylation of ethylene is obtained, exhibiting better catalytic performance (TON: >2,390,000; TOF: 100,000 h; selectivity: >99%) and stronger oxygen-resistance stability. Moreover, a substrate compatibility (122 examples) including chiral and bioactive alkenes or alcohols is achieved with up to 99% yield and 99% regioselectivity. Experimental and computational investigations show that the appropriate bite angle of aryldiphosphine ligand and the favorable interaction of 1,4-dioxane with Pd/L11 synergistically contribute to high activity and selectivity while the electron deficient phosphines originated from electron delocalization endow L11 with excellent oxygen-resistance stability.
PubMed: 38443382
DOI: 10.1038/s41467-024-46286-9 -
Beilstein Journal of Organic Chemistry 2024Kinetic studies on the intramolecular hydroamination of protected variants of 2,2-diphenylpent-4-en-1-amine were carried out under a variety of conditions with cationic...
Kinetic studies on the intramolecular hydroamination of protected variants of 2,2-diphenylpent-4-en-1-amine were carried out under a variety of conditions with cationic gold catalysts supported by phosphine ligands. The impact of ligand on gold, protecting group on nitrogen, and solvent and additive on reaction rates was determined. The most effective reactions utilized more Lewis basic ureas, and more electron-withdrawing phosphines. A DCM/alcohol cooperative effect was quantified, and a continuum of isotope effects was measured with low KIE's in the absence of deuterated alcoholic solvent, increasing to large solvent KIE's when comparing reactions in pure MeOH to those in pure MeOH-. The effects are interpreted both within the context of a classic gold π-activation/protodeauration mechanism and a general acid-catalyzed mechanism without intermediate gold alkyls.
PubMed: 38440168
DOI: 10.3762/bjoc.20.43 -
Monatshefte Fur Chemie 2024The synthesis, characterization, and reactivity of several group 4 metal complexes featuring a central anionic pyrrole moiety connected via CH linkers to two phosphine...
UNLABELLED
The synthesis, characterization, and reactivity of several group 4 metal complexes featuring a central anionic pyrrole moiety connected via CH linkers to two phosphine donors is described. Treatment of [P(NH)P-Pr] with [MCl(THF)] (M = Zr, Hf) in the presence of base yields the dimeric complexes [M(PNP)(μ-Cl)(Cl)] featuring two bridging chloride ligands. These complexes react with sodium cyclopentadienyl and SiMeI to give the mononuclear complexes [M(PNP)(η-Cp)(Cl)] and [M(PNP)(I)], respectively. The latter react with MeMgBr to form the trialkyl complexes [M(PNP)(Me)]. Upon treatment of [Ti(NMe)] with [P(NH)P-Pr] a complex with the general formula [Ti(PNP)(NMe)] is obtained. DFT calculations revealed that the most stable species is [Ti(κ- PNP)(NMe)] featuring a κ-bound PNP ligand. When [P(NH)P-Pr] is reacted with [Ti(NMe)] in CHCl complex [Ti(PNP)(Cl)(NMe)] is formed. Treatment of a solution of [P(NH)P-Pr] and [Zr(NMe)] with SiMeBr affords the anionic seven-coordinate tetrabromo complex [Zr(PNP)(Br)][HNMe]. The corresponding hafnium complex [Hf(PNP)(Br)][HNEt] is obtained in similar fashion by utilizing [Hf(NEt)] as metal precursor. All complexes are characterized by means of NMR spectroscopy. Representative complexes were also characterized by X-ray crystallography.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s00706-024-03171-x.
PubMed: 38440089
DOI: 10.1007/s00706-024-03171-x -
ACS Omega Feb 2024Discovering new applications for discarded materials, such as leather waste (LW), has proven to be an effective approach to an ecofriendly and sustainable production....
Discovering new applications for discarded materials, such as leather waste (LW), has proven to be an effective approach to an ecofriendly and sustainable production. The manufacture of halogen-free flame retardant LW containing thermoplastic polyurethane (TPU)-based samples containing an organic phosphinate (OP)-based flame retardant additive would represent an advance in this area. The effects of LW and OP levels on the thermal, flame retardant, and tensile properties of the samples using thermal gravimetric analysis (TGA), limiting oxygen index (LOI), vertical UL-94 (UL-94 V), mass loss calorimetry, and tensile tests have been assessed. OP is highly effective in LW-filled TPU. The highest UL-94 V rating of V0, LOI value of 31.4%, the lowest peak heat release rate (93 ± 3 kW/m), and total heat evolved (49 ± 2 MJ/m) values are obtained with the use of 20 wt % OP. OP is primarily promoted through the creation of a compact intumescent residue structure in the condensed phase. LW exhibits an adjuvant effect by producing nonflammable gases in the gas phase and raising the residual yield in the condensed phase. The most remarkable effect of the LW presence is observed in fire performance index (FPI) and fire growth rate (FIGRA) values. The highest FPI value of 0.49 sm/kW and the lowest FIGRA value of 0.91 kW/ms are observed with the use of 20 wt % LW.
PubMed: 38434846
DOI: 10.1021/acsomega.3c09074