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The presented work is focused on preparation and characterization of Metal-Organic Framework (MOF) with the chemical formula {[Pr4(H2TPP S)3] · nH2O}n. This type of polymer was synthesized via hydrothermal reaction with Pr(NO3)3 · 6H2O and porphyrinic ligand H2TPPS (where H2TPPS = 4,4',4",4"- (porphine-5, 10, 15,20-tetrayl)tetrakisbenzenesulfonate). Prepared MOF was characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermal and elemental analysis, and the magnetic susceptibility measurement. The crystal structure of prepared MOF is formed from Pr(III) ions arranged in 1D chains bridged by four H2TPPS ligands forming the final 3D framework with opening size 4.9 x 10.4 ² and 9.7 x 5.1 ², which are filled with water molecules. The magnetic properties of the coordination polymer were studied by magnetic susceptibility (T), and magnetization M(H) measurements in an external dc field up to 7 T in the temperature range from 1.8 to 300 K. The experimental results revealed a significant reduction of the magnetic moment below 50 K as an evidence of the presence of low-lying quasi-doublet in the energy spectrum of Pr ion in {[Pr4(H2TPPS)3] · nH2O}n. [ABSTRACT FROM AUTHOR]

Comparison of structural, chemical, and magnetic properties of Ni2FeZ (Z = In, Sn, Sb) Heusler ribbons produced by melt-spinning method is presented. The aim of work was to prepare the Heusler alloys with the appropriate chemical composition in a single step without additional thermal treatment. Scanning electron microscopy analysis revealed polycrystalline structure of all samples. It is shown that correct L21 structure of Ni2FeSb can be obtained in a single production step. On the other hand, no Heusler L21 phase (nor its variants) occur in Ni2FeSn alloy. Additionally, magnetic characterization revealed high Curie temperatures of the Heusler phases (above 600 K for Ni2FeSb and 800 K for Ni2FeIn). [ABSTRACT FROM AUTHOR]

C20H27ClN2OTi, monoclinic, P21/c (no. 14), a = 9.4006(2) Å, b = 10.8185(3) Å, c = 19.4821(5) Å, β = 97.941(1)°, V = 1962.34(9) Å3, Z = 4, Rgt(F) = 0.0270, wRref(F2) = 0.0731, T = 150(2) K.

Abstract: The decavanadate with a novel glycine–glycinato complex of copper (II) in the cationic part, (NH4)2[Cu2(H2O)4(NH3CH2COO)2(NH2CH2COO)2]H2V10O28·6H2O (1), has been prepared and characterized by elemental analysis, infrared and EPR spectroscopies. The triplet X band EPR spectrum of powdered sample evidenced magnetic interaction between the Cu(II) atoms in the dimeric unit which is probably realized through the bridging water molecules in this part of the complex. A single crystal X-ray diffraction study revealed that the structure of 1 contains cationic copper complex with a rare Cu(H2O)2Cu double bridge. In this cation, a simultaneous bidentate N, O– and monodentate O– coordination of glycine to the same central atom was observed for the first time. [ABSTRACT FROM AUTHOR]

Multidrug-resistant bacterial infections continue to be a rising global health concern. Herein, we describe the development of a novel class of 3-substituted benzoazepinedione derivatives with promising antibacterial activity. The pivotal compound, benzoazepinedione carboxylate 9, represents a highly electrophilic Michael acceptor, enabling divergent access to a wide range of thia-, aza-, oxa-, and phospha-Michael adducts. Notably, most prepared compounds exhibited potent antibacterial activity against both drug-susceptible and drug-resistant strains of Staphylococcus aureus (MIC 90 of up to 2 μg mL -1 ). The cytotoxicity assessment in the VERO6 cell line revealed that thia-adduct 10d (IC 50 of 36.5 μg mL -1 ) exhibits lower toxicity compared to its parent electrophile 9 (IC 50 of 14.3 μg mL -1 ), which is in agreement with the hypothesis of covalently modified prodrugs. Additionally, stability studies of the prepared compounds in CD 3 OD and a DMSO-PBS mixture confirmed that thia-Michael adducts 10 are stable under neutral conditions while dynamic under mildly basic conditions. Moreover, 3D reconstructed tissue models (human lung epithelial EpiAirway™ and a human small intestine model) did not exhibit a viability decrease below 80% of the untreated control at all concentrations tested, indicating tolerance to higher concentrations of potential drugs and prodrugs.

Two In(III) - pyridinecarboxylates ([In(Pic) 2 (NO 3 )(H 2 O)] (InPic; HPic = picolinic acid), [In(HDpic)(Dpic)(H 2 O) 2 ]·5H 2 O (InDpic; H 2 Dpic = dipicolinic acid), have been synthesized by one-step procedure. The complexes composition was confirmed by physicochemical analyses and X-ray diffraction confirmed molecular structure of both complexes. Moreover, complex species speciation was described in both systems by potentiometry and 1 H NMR spectroscopy and mononuclear complex species were determined; [In(Pic)] 2+ (logβ 011  = 6.94(4)), [In(Pic) 2 ] + (logβ 021  = 11.98(9)), [In(Dpic)] + (logβ 011  = 10.42(6)), [In(Dpic) 2 ] - (logβ 021  = 17.58(7)) and [In(Dpic) 2 (OH)] 2- (logβ - 121  = 10.18(6)). To confirm the complexes stability in 1 % DMSO, 1 H NMR spectra were measured (immediately after dissolution up to 96 h). Antimicrobial and anticancer assays indicate a more significant sensitivity of S. aureus bacteria and MDA-MB-231 cancer cells to the InPic complex (IC 50  = 25 and 340.7 μM) than to the InDpic (IC 50  = 50 and 975.4 μM). The interaction and binding mechanism of picolinic/dipicolinic acid and their indium(III) complexes with HSA (human serum albumin) were studied using fluorescence and CD spectroscopy. The results confirmed that the studied compounds had bound successfully to HSA, and the binding parameters and constants (K SV , K q , K b ) were calculated together with the number of binding sites. The binding forces were identified based on calculated thermodynamic parameters (ΔG, ΔH, ΔS). Synchronous spectra were used to study the microenvironment of Tyr and Trp residues and displacement assays revealed that site I was the preferred binding site. After binding, conformational changes were found to have occurred in the HSA molecule and the % α-helical content had decreased., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Silver(I) complexes with proline and hydroxyproline were synthesized and structurally characterized and crystal structure analysis shows that the formulas of the compounds are {[Ag 2 (Pro) 2 (NO 3 )]NO 3 } n (AgPro) (Pro = L-proline) and {[Ag 2 (Hyp) 2 (NO 3 )]NO 3 } n (AgHyp) (Hyp = trans -4-hydroxy-L-proline). Both complexes crystallize in the monoclinic lattice with space group P 2 1 with a carboxylate bidentate-bridging coordination mode of the organic ligands Pro and Hyp (with NH 2 + and COO - groups in zwitterionic form). Both complexes have a distorted seesaw (C 2v ) geometry around one silver(I) ion with τ 4 values of 58% (AgPro) and 51% (AgHyp). Moreover, the results of spectral and thermal analyses correlate with the structural ones. 1 H and 13 C NMR spectra confirm the complexes species' presence in the DMSO biological testing medium and their stability in the time range of the bioassays. In addition, molar conductivity measurements indicate complexes' behaviour like 1 : 1 electrolytes. Both complexes showed higher or the same antibacterial activity against Bacillus cereus , Pseudomonas aeruginosa and Staphylococcus aureus as AgNO 3 (MIC = 0.063 mM) and higher than silver(I) sulfadiazine (AgSD) (MIC > 0.5 mM) against Pseudomonas aeruginosa . In addition, complex AgPro exerted a strong cytotoxic effect against the tested MDA-MB-231 and Jurkat cancer cell lines (IC 50 values equal to 3.7 and 3.0 μM, respectively) compared with AgNO 3 (IC 50 = 6.1 (5.7) μM) and even significantly higher selectivity than cisplatin (cisPt) against MDA-MB-231 cancer cell lines (SI = 3.05 (AgPro); 1.16 (cisPt), SI - selectivity index). The binding constants and the number of binding sites ( n ) of AgPro and AgHyp complexes with bovine serum albumin (BSA) were determined at four different temperatures, and the zeta potential of BSA in the presence of silver(I) complexes was also measured. The in ovo method shows the safety of the topical and intravenous application of AgPro and AgHyp. Moreover, the complexes' bioavailability was verified by lipophilicity evaluation from the experimental and theoretical points of view.

New functionalities were added to biocompatible polycaprolactone nanofiber materials through the co-encapsulation of chlorin e6 trimethyl ester (Ce6) photogenerating singlet oxygen and absorbing light both in the blue and red regions, and using 4-(N-(aminopropyl)-3-(trifluoromethyl)-4-nitrobenzenamine)-7-nitrobenzofurazan, NO-photodonor (NOP), absorbing light in the blue region of visible light. Time-resolved and steady-state luminescence, as well as absorption spectroscopy, were used to monitor both photoactive compounds. The nanofiber material exhibited photogeneration of antibacterial species, specifically nitric oxide and singlet oxygen, upon visible light excitation. This process resulted in the efficient photodynamic inactivation of E. coli not only close to nanofiber material surfaces due to short-lived singlet oxygen, but even at longer distances due to diffusion of longer-lived nitric oxide. Interestingly, nitric oxide was also formed by processes involving photosensitization of Ce6 during irradiation by red light. This is promising for numerous applications, especially in the biomedical field, where strictly local photogeneration of NO and its therapeutic benefits can be applied using excitation in the "human body phototherapeutic window" (600-850 nm). Generally, due to the high permeability of red light, the photogeneration of NO can be achieved in any aqueous environment where direct excitation of NOP to its absorbance in the blue region is limited., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)