Eu+3-doped chalcone substituted cyclotriphosphazenes: Synthesis, characterizations, thermal and dielectrical properties

The first peptide derivatives of dioxybiphenyl-bridged spiro cyclotriphosphazenes: In vitro cytotoxicity activities and DNA damage studies

In this study, we aimed to synthesize new peptide-substituted cyclotriphosphazenes from a series of tyrosine-based peptides and dioxyphenyl-substituted spirocyclotriphosphazenes, and to evaluate their in vitro cytotoxicity and genotoxicity activities. Genotoxicity studies were conducted to understand whether the cytotoxic compounds cause cell death through DNA damage. The structures of the novel series of phosphazenes were characterized by FT-IR, elemental analysis, MS, 1D (³¹P, ¹H, and ¹³C-APT NMR), and 2D (HETCOR) NMR spectroscopic techniques. In vitro cytotoxic activities were carried out against human breast (MCF-7), ovarian (A2780), prostate (PC-3), colon (Caco-2) cancer cell lines and human normal epithelial cell line (MCF-10A) at different concentrations by using an MTT assay. The compounds showed considerable reductions in cell viability against all human cancer cell lines. Especially, the compounds exhibited notable effects in A2780 cell lines (p < 0.05). The IC₅₀ values of the compounds in the A2780 cell line were calculated to be 1.914 µM for TG, 20.21 µM for TV, 20.45 µM for TA, 4.643 µM for TP, 5.615 µM for BTG, 1.047 µM for BTV, 27.02 µM for BTA, 0.7734 µM for BTP, 21.5 µM for DTG, 1.65 µM for DTV, 2.89 µM for DTA and 4.599 µM for DTP. DNA damage studies of the compounds were conducted by the comet assay method using tail length, tail density, olive tail moment, head length, and head density parameters, and the results showed that the cell death occurred through DNA damage mechanism. In a nutshell, these compounds show promising cytotoxic effects and can be considered powerful candidate molecules for pharmaceutical applications.

Fire Retardancy and Dielectric Strength of Cyclotriphosphazene Compounds with Schiff Base and Ester Linking Units Attached to the Electron-Withdrawing Side Arm

A series of compounds with Schiff base and ester linking units attached to the electron-withdrawing side arm (Cl, NO₂, and OH) have been successfully synthesized through four schemes of the chemical route. These compounds were characterized using Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance spectroscopy (NMR), and Carbon, Hydrogen and Nitrogen (CHN) elemental analysis. The epoxy resin was used as a matrix of molding to observe the refinement of fire-retardant properties of the modified cyclotriphosphazene compounds. The fire-retardant testing was done using Limiting Oxygen Index (LOI). The LOI value of pure epoxy resin was increased from 22.75% to 24.71% when incorporated with 1 wt.% of hexasubstituted cyclotriphosphazene (HCCP). Interestingly, all the final compounds gave a positive increment in the LOI value and the highest LOI value was obtained from the compound containing a nitro side arm with LOI value of 26.90%. In order to understand the thermal stability of these compounds, Thermogravimetric Analysis (TGA) was carried out. The compound with the nitro group at the terminal end has the highest char residue which is 34.2% at 700 °C. This indicated that the presence of the nitro withdrawing group was able to enhance the fire retardancy of the materials. Based on SEM observation, the shape of the final compound’s char residue demonstrated the formation of a porous protective layer with a dense surface. The dielectric property was conducted according to ASTM D149 AC breakdown voltage to determine its dielectric strength. The results showed that the highest dielectric strength value belonged to the compound containing a nitro group side arm with 24.41 kV/mm⁻¹ due to the π electron delocalization.

Luminescent Coatings Based on (3-Aminopropyl)triethoxysilane and Europium Complex β-Diketophosphazene

The reaction of β-diketophosphazene with the europium (III) salt synthesized the corresponding metal complex which was structured with (3-aminopropyl)triethoxysilane and treated with dibenzoylmethane for additional coordination of europium atoms. The polymer thus obtained exhibits luminescence with a maximum of 615 nm, which is characteristic of europium. The polymer is thermally stable up to 300 °C, the coating based on it has a contact angle of 101°, and the adhesive strength of the coating to non-finished glass (according to ISO 2409: 2013) is 1 point.

A Review on Synthesis, Structural, Flame Retardancy and Dielectric Properties of Hexasubstituted Cyclotriphosphazene

Hexachlorocyclotriphosphazene is a ring compound consisting of an alternating phosphorus and nitrogen atom with two chlorine substituents attached to the phosphorus atom. The six chlorine atoms attached to this cyclo compound can be substituted with any different nucleophile that leads to changes in different chemical and physical properties. The major topics that were investigated in this research are the flame retardancy and dielectric properties of cyclotriphosphazene compounds. Cyclotriphosphazene compounds have high potential to act as a flame retardant, and this compound consists of two active elements attributed to its high flame-retardant character. This compound also demonstrated good ability as a flame retardant due to its low toxicity and less smoke produced. In addition, cyclotriphosphazene compounds were also investigated for their dielectric properties. Cyclotriphosphazene has high potential in the electrical field since it has dielectric properties that can be widely studied in the investigation of any potential application. This review presented literature studies focused on recent research development and studies in the field of cyclotriphosphazene that focused on synthesis, structural, flame retardancy, and dielectric properties of hexachlorocyclotriphosphazene compounds.

Functional chalcone-substituted tetrakis-metallophthalocyanines: Synthesis and spectroscopic characterization

In this study, a new phthalonitrile derivative, ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile, and four peripherally ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy) tetrasubstituted new Ni(II), Zn(II), Co(II), and Cu(II) phthalocyanine derivatives are synthesized and characterized. ( E)-4-(3-(3-(3-Methoxyphenyl)acryloyl)phenoxy)phthalonitrile is synthesized by heating ( E)-1-(3-hydroxyphenyl)-3-(3-methoxyphenyl)prop-2-en-1-one and 4-nitrophthalonitrile in the presence of K2CO3 in dry DMF at 60°C for 96 h. The metallophthalocyanines are prepared by cyclotetramerization of ( E)-4-(3-(3-(3-methoxyphenyl)acryloyl)phenoxy)phthalonitrile with NiCl2, Zn(CH3COO)2, CoCl2, and CuCl2 in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene. Characterization of the new compounds is performed by means of IR, 1H NMR, 13C NMR, and mass and UV-Vis spectroscopy techniques.

Synthesis and anticancer activity of cyclotriphosphazenes functionalized with 4-methyl-7-hydroxycoumarin

The synthesis of three cyclotriphosphazenes derivatives bearing 4-methyl-7-hydroxycoumarin moieties with the numbers of 2, 4, or 6 were reported, and their antitumor activities were test.

Preparation and Characterization of Styrene Bearing Diethanolamine Side Group, Styrene Copolymer Systems, and Their Metal Complexes

The two copolymer systems of styrene bearing diethanol amine side group and styrene were prepared by free radical polymerization method at 60°C in presence of 1,4-dioxane as solvent and AIBN as initiator. Their metal complexes were prepared by reaction of the copolymer used as ligand P(DEAMSt-co-St)L′′ and Ni(II) and Co(II) metal ions, which was carried out in presence of ethanol and NaOH at 65°C for 48 h in pH = 7.5. The structures of the copolymers used as ligand and metal complexes were identified by FT-IR, 1H-NMR spectra, and elemental analysis. The properties of the copolymers used as ligand and metal complexes were characterized by SEM-EDX, AAS, DSC, TGA, and DTA techniques. Then, the electrical properties of the copolymers and metal complexes were examined as a function of the temperature and frequency, and the activation energies (Ea) were estimated with conductivity measurements.