Stabilnost kompleksa nekih lantanida s derivatima kumarina. II. Neodimij(III)-acenokumarol

A complex of neodymium(III) with 4-hydroxy-3-[1-(4-nitrophenyl)-3-oxobutyl]-2H-1-benzopyran-2-one (acenocoumarol) was synthesized by mixing water solutions of neodymium(III) nitrate and the ligand (metal to ligand molar ratio of 1:3). The complex was characterized and identified by elemental analysis, conductivity, IR, 1H NMR and mass spectral data. DTA and TGA were applied to study the composition of the compound. Elemental and mass spectral analysis of the complex indicated the formation of a compound of the composition NdR3x6H2O, where R = C19H14NO6-. The reaction of neodymium(III) with 4-hydroxy-3-[1-(4-nitrophenyl)-3-oxobutyl]-2H-1-benzopyran-2-one was studied in detail by the spectrophotometric method. The stepwise formation of three complexes, vis., NdR2+, NdR2+ and NdR3 was established in the pH region studied (pH 3.0-7.5). The equilibrium constants for 1:1, 1:2 and 1:3 complexes were determined to be log K1 = 6.20 ± 0.06; log K2 = 3.46 ± 0.07 and log K3 = 2.58 ± 0.05, respectively.Neodimijev(III) kompleks s acenokumarolom pripravljen je mješajući vodenu otopinu neodimijevog(III) nitrata i liganda u molarnom omjeru metala i liganda 1:3. Kompleks je karakteriziran i identificiran elementarnom analizom, konduktometrijom, IR, 1H NMR, masenom spektroskopijom, DTA i TGA. Analize ukazuju na sastav kompleksa NdR3.6H2O, gdje je R = C19H14NO6-. Reakcija neodimij(III) s acenokumarolom praćena je spektrofotometrijski. U pH području 3,0 do 7,5 utvrđeno je postupno stvaranje triju kompleksa, NdR2+, NdR2+ i NdR3. Konstante ravnoteže za 1:1, 1:2 i 1:3 komplekse bile su log K1 = 6,20 0,06, log K2 = 3,46 0,07, odnosno log K3 = 2,58 0,05

Stabilnost kompleksa nekih lantanida s derivatima kumarina. II. Neodimij(III)-acenokumarol

A complex of neodymium(III) with 4-hydroxy-3-[1-(4-nitrophenyl)-3-oxobutyl]-2H-1-benzopyran-2-one (acenocoumarol) was synthesized by mixing water solutions of neodymium(III) nitrate and the ligand (metal to ligand molar ratio of 1:3). The complex was characterized and identified by elemental analysis, conductivity, IR, 1H NMR and mass spectral data. DTA and TGA were applied to study the composition of the compound. Elemental and mass spectral analysis of the complex indicated the formation of a compound of the composition NdR3x6H2O, where R = C19H14NO6-. The reaction of neodymium(III) with 4-hydroxy-3-[1-(4-nitrophenyl)-3-oxobutyl]-2H-1-benzopyran-2-one was studied in detail by the spectrophotometric method. The stepwise formation of three complexes, vis., NdR2+, NdR2+ and NdR3 was established in the pH region studied (pH 3.0-7.5). The equilibrium constants for 1:1, 1:2 and 1:3 complexes were determined to be log K1 = 6.20 ± 0.06; log K2 = 3.46 ± 0.07 and log K3 = 2.58 ± 0.05, respectively.Neodimijev(III) kompleks s acenokumarolom pripravljen je mješajući vodenu otopinu neodimijevog(III) nitrata i liganda u molarnom omjeru metala i liganda 1:3. Kompleks je karakteriziran i identificiran elementarnom analizom, konduktometrijom, IR, 1H NMR, masenom spektroskopijom, DTA i TGA. Analize ukazuju na sastav kompleksa NdR3.6H2O, gdje je R = C19H14NO6-. Reakcija neodimij(III) s acenokumarolom praćena je spektrofotometrijski. U pH području 3,0 do 7,5 utvrđeno je postupno stvaranje triju kompleksa, NdR2+, NdR2+ i NdR3. Konstante ravnoteže za 1:1, 1:2 i 1:3 komplekse bile su log K1 = 6,20 0,06, log K2 = 3,46 0,07, odnosno log K3 = 2,58 0,05

Stabilnost kompleksa nekih lantanida s derivatima kumarina. I. Cerijev(III)-4-metil-7-hidroksikumarin

A complex of cerium(III) with 4-methyl-7-hydroxycoumarin was synthesized by mixing water solutions of cerium(III) nitrate and 4-methyl-7-hydroxycoumarin sodium salt in a metal-to-ligand molar ratio of 1:2. The complex was characterized and identified by elemental analysis, conductometry, IR, 1H and 13C NMR-spectroscopy, mass spectral data, DTA and TGA. Thermal analysis of the complex indicated the formation of a compound of the composition Ce(R)2.(OH).5H2O, R standing for the ligand. The reaction of cerium(III) with 4-methyl-7-hydroxycoumarin was studied in detail by spectrophotometric method. The stepwise formation of two complexes, vis., CeR2+ and CeR2+, was established in the pH region studied. The equilibrium constants for 1:1 and 1:2 complexes were determined to be 10.72 and 9.22, respectively.Kompleks cerijevog(III) iona s 4-metil-7-hidroksikumarinom priređen je mješanjem vodene otopine cerijevog(III) nitrata i 4-metil-7-hidroksikumarin natrija u moalrnom omjeru 1:2. Kompleks je karakteriziran i identificiran elementarnom analizom, konduktometrijski, IR, 1H i 13C NMR-spektroskopijom, DTA, TGA i spektrometrijom masa. Termičkom analizom utvrđen je sastav kompleksa kao Ce(R)2.(OH).5H2O. Reakcija cerijevog(III) iona s 4-metil-7-hidroksikumarinom praćena je spektrofotometrijski. U proučavanom pH području utvrđeno je stupnjevito nastajanje dva kompleksa, CeR2+ i CeR2+. Konstante ravnoteže za 1:1 i 1:2 komplekse bile su 10,72, odnosno 9,22

Stabilnost kompleksa nekih lantanida s derivatima kumarina. I. Cerijev(III)-4-metil-7-hidroksikumarin

A complex of cerium(III) with 4-methyl-7-hydroxycoumarin was synthesized by mixing water solutions of cerium(III) nitrate and 4-methyl-7-hydroxycoumarin sodium salt in a metal-to-ligand molar ratio of 1:2. The complex was characterized and identified by elemental analysis, conductometry, IR, 1H and 13C NMR-spectroscopy, mass spectral data, DTA and TGA. Thermal analysis of the complex indicated the formation of a compound of the composition Ce(R)2.(OH).5H2O, R standing for the ligand. The reaction of cerium(III) with 4-methyl-7-hydroxycoumarin was studied in detail by spectrophotometric method. The stepwise formation of two complexes, vis., CeR2+ and CeR2+, was established in the pH region studied. The equilibrium constants for 1:1 and 1:2 complexes were determined to be 10.72 and 9.22, respectively.Kompleks cerijevog(III) iona s 4-metil-7-hidroksikumarinom priređen je mješanjem vodene otopine cerijevog(III) nitrata i 4-metil-7-hidroksikumarin natrija u moalrnom omjeru 1:2. Kompleks je karakteriziran i identificiran elementarnom analizom, konduktometrijski, IR, 1H i 13C NMR-spektroskopijom, DTA, TGA i spektrometrijom masa. Termičkom analizom utvrđen je sastav kompleksa kao Ce(R)2.(OH).5H2O. Reakcija cerijevog(III) iona s 4-metil-7-hidroksikumarinom praćena je spektrofotometrijski. U proučavanom pH području utvrđeno je stupnjevito nastajanje dva kompleksa, CeR2+ i CeR2+. Konstante ravnoteže za 1:1 i 1:2 komplekse bile su 10,72, odnosno 9,22

Pyridine Heterocycles in the Therapy of Oncological Diseases

Oncological diseases pose a major challenge for modern medicine. Heterocyclic compounds play a vital role in modern medical and pharmaceutical science as most medicinal substances incorporate them. Nitrogen-containing heterocycles serve as the basis of numerous drugs and, therefore, are deeply involved in the design and synthesis of promising new therapeutic agents. Pyridine or pyrimidine scaffolds, with a number of substituents attached, comprise a large portion of FDA-approved drugs. They are chemically stable in the human body, manifest an affinity for DNA via hydrogen bonding, and present an opportunity for the development of novel anticancer agents. A large number of pyridine-based molecules are synthesized and tested for anticancer activity each year. The present chapter aims to introduce the most current synthetic approaches, published in scientific literature, and would also elaborate on structure-activity relationships described therein

Peculiarities of the Spatial and Electronic Structure of 2-Aryl-1,2,3-Triazol-5-Carboxylic Acids and Their Salts on the Basis of Spectral Studies and DFT Calculations

The molecular structure and vibrational spectra of six 1,2,3-triazoles-containing molecules with possible anticancer activity were investigated. For two of them, the optimized geometry was determined in the monomer, cyclic dimer and stacking forms using the B3LYP, M06-2X and MP2 methods implemented in the GAUSSIAN-16 program package. The effect of the para-substitution on the aryl ring was evaluated based on changes in the molecular structure and atomic charge distribution of the triazole ring. An increment in the positive N4 charge was linearly related to a decrease in both the aryl ring and the carboxylic group rotation, with respect to the triazole ring, and by contrast, to an increment in the pyrrolidine ring rotation. Anionic formation had a larger effect on the triazole ring structure than the electronic nature of the different substituents on the aryl ring. Several relationships were obtained that could facilitate the selection of substituents on the triazole ring for their further synthesis. The observed IR and Raman bands in the solid state of two of these compounds were accurately assigned according to monomer and dimer form calculations, together with the polynomic scaling equation procedure (PSE). The large red-shift of the C=O stretching mode indicates that strong H-bonds in the dimer form appear in the solid state through this group

Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019

Summary Background Reducing the burden of death due to infection is an urgent global public health priority. Previous studies have estimated the number of deaths associated with drug-resistant infections and sepsis and found that infections remain a leading cause of death globally. Understanding the global burden of common bacterial pathogens (both susceptible and resistant to antimicrobials) is essential to identify the greatest threats to public health. To our knowledge, this is the first study to present global comprehensive estimates of deaths associated with 33 bacterial pathogens across 11 major infectious syndromes. Methods We estimated deaths associated with 33 bacterial genera or species across 11 infectious syndromes in 2019 using methods from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, in addition to a subset of the input data described in the Global Burden of Antimicrobial Resistance 2019 study. This study included 343 million individual records or isolates covering 11 361 study-location-years. We used three modelling steps to estimate the number of deaths associated with each pathogen: deaths in which infection had a role, the fraction of deaths due to infection that are attributable to a given infectious syndrome, and the fraction of deaths due to an infectious syndrome that are attributable to a given pathogen. Estimates were produced for all ages and for males and females across 204 countries and territories in 2019. 95% uncertainty intervals (UIs) were calculated for final estimates of deaths and infections associated with the 33 bacterial pathogens following standard GBD methods by taking the 2·5th and 97·5th percentiles across 1000 posterior draws for each quantity of interest. Findings From an estimated 13·7 million (95% UI 10·9–17·1) infection-related deaths in 2019, there were 7·7 million deaths (5·7–10·2) associated with the 33 bacterial pathogens (both resistant and susceptible to antimicrobials) across the 11 infectious syndromes estimated in this study. We estimated deaths associated with the 33 bacterial pathogens to comprise 13·6% (10·2–18·1) of all global deaths and 56·2% (52·1–60·1) of all sepsis-related deaths in 2019. Five leading pathogens—Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Klebsiella pneumoniae, and Pseudomonas aeruginosa—were responsible for 54·9% (52·9–56·9) of deaths among the investigated bacteria. The deadliest infectious syndromes and pathogens varied by location and age. The age-standardised mortality rate associated with these bacterial pathogens was highest in the sub-Saharan Africa super-region, with 230 deaths (185–285) per 100 000 population, and lowest in the high-income super-region, with 52·2 deaths (37·4–71·5) per 100 000 population. S aureus was the leading bacterial cause of death in 135 countries and was also associated with the most deaths in individuals older than 15 years, globally. Among children younger than 5 years, S pneumoniae was the pathogen associated with the most deaths. In 2019, more than 6 million deaths occurred as a result of three bacterial infectious syndromes, with lower respiratory infections and bloodstream infections each causing more than 2 million deaths and peritoneal and intra-abdominal infections causing more than 1 million deaths. Interpretation The 33 bacterial pathogens that we investigated in this study are a substantial source of health loss globally, with considerable variation in their distribution across infectious syndromes and locations. Compared with GBD Level 3 underlying causes of death, deaths associated with these bacteria would rank as the second leading cause of death globally in 2019; hence, they should be considered an urgent priority for intervention within the global health community. Strategies to address the burden of bacterial infections include infection prevention, optimised use of antibiotics, improved capacity for microbiological analysis, vaccine development, and improved and more pervasive use of available vaccines. These estimates can be used to help set priorities for vaccine need, demand, and development