Search

A novel series of 1 : 1 cocrystals of 2‐cyanoguanidinophenytoin (CNG‐DPH) with primary, secondary, and tertiary aliphatic amines has been presented through this work. The antimicrobial activities of all new CNG‐DPH‐amine cocrystals were studied. The existence of cocrystals has been proven through crystal structure results. The 5‐Oxo‐4,4‐diphenylimidazolidin‐2‐ylidenecyanamide‐piperidine cocrystal (10) is located in an orthorhombic crystal system, and the cocrystal is connected via the N−H−N hydrogen bond between the cyanide group and the piperidine molecule. Hirshfeld surface analysis authenticated supramolecular contacts. Ring puckering analysis revealed a chair stereochemistry at the 6‐membered piperidine. The crystal packing has been stabilized through intermolecular forces, hydrogen bonds, and interactions within the gravity center of rings (Cg). The antimicrobial activities of the newly synthesized compounds were only effective against Gram‐positive bacteria, demonstrating that the antibacterial spectrum of these compounds was restricted. In vitro cytotoxicity of the synthesized cocrystals was assessed in normal cells, giving the highest half‐maximal inhibitory concentration (IC50) ratio (637.63 μg/ml) and the lowest value (181.98 μg/ml). [ABSTRACT FROM AUTHOR]

This study demonstrates the significant impact of gallium ions on the local structure and physical, optical, and biological properties of borosilicate glasses. The glass composition, denoted as BSCZG, with the formula (50B2O3–5SiO2–15ZnO–(30-x)CaO–xGa2O3), where 0 ≤ x ≤ 20 mol%, was synthesized using the melt quenching technique. X-ray diffraction (XRD) patterns confirmed the amorphous nature of the BSCZG samples, presenting a broad hump. Analysis of the attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) results revealed the transformation of BO4 units into BO3 units, accompanied by generating non-bridging oxygens (NBOs) with increasing Ga2O3 content. As Ga2O3 content increased from 0 to 20 mol%, the experimental density (ρexp) and molar volume (Vm) of BSCZG glasses also increased, shifting from 2.70 to 3.14 g cm−3 and from 24.66 to 29.58 cm3 mol−1, respectively were also observed. This increment in Vm can be attributed to the rise in NBOs. Furthermore, an inverse relationship was observed between the optical band gap (Eopt) and optical band tail energy (EU); Eopt decreased from 3.27 to 3.08 eV, while EU increased from 0.20 to 0.25 eV with the Ga2O3 content rising from 0 to 20 mol%. The refractive index (n) of BSCZG glasses also increased from 1.52 to 1.57 as Ga2O3 content increased. Additionally, XRD patterns and ATR-FTIR spectra of BSCZG confirmed the formation of hydroxyapatite (HA) following assessment in simulated body fluid (SBF) for 3, 7, and 14 days. Protein adsorption in phosphate-buffered saline (PBS), cell viability (MTT) assays using Vero cells, and immersion in SBF were conducted to assess the bioactivity of the prepared samples. The results indicated that gallium ions containing borosilicate glasses exhibited significantly higher degradation rates than the Ga-free glass sample. Despite increased chemical durability, the substituted glasses displayed a favorable in vitro bioactive response. SBF results suggested that BSCZG glasses were more likely to contain higher concentrations of HA due to the elevated content of Ga ions. In conclusion, borosilicate glasses incorporating Ga3+ ions demonstrate promising effects for both optical and biomedical applications. [ABSTRACT FROM AUTHOR]

The optimized synthesis of [5-oxo-4,4-diphenylimidazolidin-2-ylidene]cyanamide, which is known as 2-cyanoguanidinophenytoin (CNG-DPH) (3), and (imidazo[4,5-d]imidazole-2,5-diylidine)dicyanamide (4) has been reported in the present work. Furthermore, new Mannich bases derived from CNG-DPH were synthesized via its reaction with formaldehyde and using the corresponding amines, piperidine (base 5), and morpholine (base 6). Also, the antimicrobial activity and X-ray crystal structures for CNG-DPH and their Mannich bases were studied. The bases 3 and 6 crystallized in a monoclinic system; the crystal structure of 3 containing four molecules in the unit cell with a P21/c space group. The unit cell of 6 has eight molecules with a C2/c space group. The inter and intra hydrogen bond contacts packed and stabilized both of the structures. The morpholine ring of base 6 demonstrated a distinctive chair configuration. Mannich bases 5 and 6 showed promising antimicrobial effects. base 4 has a greater percentage for in vitro cytotoxicity (IC50) against normal cells, whereas 3 has the lowest ratio. [ABSTRACT FROM AUTHOR]

Ternary silicate glass (69SiO2–27CaO–4P2O5) was synthesized with the sol–gel route, and different percentages of germanium oxide GeO2 (6.25, 12.5, and 25%) and polyacrylic acid (PAA) were added. DFT calculations were performed at the B3LYP/LanL2DZ level of theory for molecular modelling. X-ray powder diffraction (XRPD) was used to study the effect of GeO2/PAA on the structural properties. The samples were further characterized using DSC, ART-FTIR, and mechanical tests. Bioactivity and antibacterial tests were assessed to trace the influence of GeO2 on biocompatibility with biological systems. Modelling results demonstrate that molecular electrostatic potential (MESP) indicated an enhancement of the electronegativity of the studied models. While both the total dipole moment and HOMO/LUMO energy reflect the increased reactivity of the P4O10 molecule. XRPD results confirmed the samples formation and revealed the correlation between the crystallinity and the properties, showing that crystalline hydroxyapatite (HA) is clearly formed in the highest percentages of GeO2, proposing 25% as a strong candidate for medical applications, consistent with the results of mechanical properties and the rest of the characterization results. Simulated body fluid (SBF) in vitro experiments showed promising biocompatibility. The samples showed remarkable antimicrobial and bioactivity, with the strongest effect at 25%. The experimental findings of this study revealed that the incorporation of GeO2 into the glass in terms of structural characteristics, bioactivity, antimicrobial properties, and mechanical properties is advantageous for biomedical fields and especially for dental applications. [ABSTRACT FROM AUTHOR]