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Two new Sm(III) complexes, [Sm(L1)2Cl(H2O)]·3H2O and [Sm(L2)2Cl(H2O)]·2H2O, where HL1 is (E)-4-bromo-2-(((4-(2-hydroxyethyl)phenyl)imino)methyl)phenol and HL2 is (E)-2-(((4-(2-hydroxyethyl)phenyl)imino)methyl)-4-methoxyphenol, are reported. From the spectral data, it was deduced that the two Schiff base ligands existed as monobasic bidentate ON bonded to samarium(III) through deprotonated hydroxyl oxygen and azomethine nitrogen adopting an octahedral environment around Sm(III). The optimized structures, molecular electrostatic potential, and the energies HOMO and LUMO were calculated using DFT/B3LYP calculations employing the Gaussian 09 program. The antimicrobial efficacy of complexes and their parent ligands have been tested in vitro against various strains of bacteria and fungus. The antimicrobial activity of the new complexes has been enhanced compared to their parent free ligands. MTT assay was used to assess the in vitro cytotoxicity of the ligands and their Sm(III) complexes against the human breast cancer cell line (MCF-7) and human liver carcinoma cell line (Hep-G2). The CT-DNA binding constants of the interaction have been calculated and follow the order SmL1 > SmL2.

Organometallic macromolecular polymers and dendrimers constructed with various chromophores and antimicrobial species are attracting considerable attention. Interest in these materials stems from their exceptional properties and potential applications in the industry as biomedical and photoactive agents, as well as their use as sensors. Over the past few decades, the exponential growth of many new classes of metallo-macromolecules that address these issues has been illustrated. Metal-based antimicrobial macromolecules are rising due to the combination of the multiple interactions of the unique properties of metallic moieties and the effect of the bioactive species. Progress in the field of organometallic photoactive materials derives from their broad applications, including photonic switches and upconversion lasers, in addition to sensors and electronic devices. The aim of this inclusive review is to highlight the design and properties of several types of bioactive and drug delivery macromolecules containing metallic moieties as well as metallopolymers and dendrimers containing organic light-emitting diodes.

In this study, the acid chlorides of pyrazolo[3,4-d]pyrimidine compounds were prepared and reacted with a number of nucleophiles. The novel compounds were experimentally tested via enzyme assay and they showed cyclooxygenase-2 inhibition activity in the middle micro molar range (4b had a COX-1 IC50 of 26 µM and a COX-2 IC50 of 34 µM, 3b had a COX-1 IC50 of 19 µM and a COX-2 IC50 of 31 µM, 3a had a COX-2 IC50 of 42 µM). These compounds were analyzed via docking and were predicted to interact with some of the COX-2 key residues. Our best hit, 4d (COX-1 IC50 of 28 µM, COX-2 IC50 of 23 µM), appears to adopt similar binding modes to the standard COX-2 inhibitor, celecoxib, proposing room for possible selectivity. Additionally, the resultant novel compounds were tested in several in vivo assays. Four compounds 3a (COX-2 IC50 of 42 µM), 3d, 4d and 4f were notable for their anti-inflammatory activity that was comparable to that of the clinically available COX-2 inhibitor celecoxib. Interestingly, they showed greater potency than the famous non-steroidal anti-inflammatory drug, Diclofenac sodium. In summary, these novel pyrazolo[3,4-d]pyrimidine analogues showed interesting anti-inflammatory activity and could act as a starting point for future drugs.

This article belongs to the Section Inorganic Chemistry., The development of synthesis methods to access advanced materials, such as magnetic materials that combine multimetallic phosphide phases, remains a worthy research challenge. The most widely used strategies for the synthesis of magnetic transition metal phosphides (TMPs) are organometallic approaches. In this study, Fe-containing homometallic dendrimers and Fe/Co-containing heterometallic dendrimers were used to synthesize magnetic materials containing multimetallic phosphide phases. The crystalline nature of the nearly aggregated particles was indicated for both designed magnetic samples. In contrast to heterometallic samples, homometallic samples showed dendritic effects on their magnetic properties. Specifically, saturation magnetization (Ms) and coercivity (Hc) decrease as dendritic generation increases. Incorporating cobalt into the homometallic dendrimers to prepare the heterometallic dendrimers markedly increases the magnetic properties of the magnetic materials from 60 to 75 emu/g. Ferromagnetism in homometallic and heterometallic particles shows different responses to temperature changes. For example, heterometallic samples were less sensitive to temperature changes due to the presence of Co2P in contrast to the homometallic ones, which show an abrupt change in their slopes at a temperature close to 209 K, which appears to be related to the Fe2P ratios. This study presents dendrimers as a new type of precursor for the assembly of magnetic materials containing a mixture of iron- and cobalt-phosphides phases with tunable magnetism, and provides an opportunity to understand magnetism in such materials., The authors acknowledge the Libyan Ministry of Education for financial support and thank funding from the UPEI Doctoral Research Support Program. We also acknowledge the financial support from Spanish Ministerio de Economía y Competitividad (PID2020-113558RB-C41) and Gobiernodel Principado de Asturias (GRUPIN-ID2018-170).

Paracetamol (acetaminophen) is a common painkiller and antipyretic drug used globally. Attachment of paracetamol to a series of organoiron dendrimers was successfully synthesized. The aim of this study is to combine the benefits of the presence of these redox-active organoiron dendrimers, their antimicrobial activities against some human pathogenic Gram-positive, and the therapeutic characteristics of paracetamol. The antimicrobial activity of these dendrimers was investigated and tested with a minimum inhibitory concentration and this has been reported. Some of these newly synthesized dendrimers exhibited the highest inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE), and Staphylococcus warneri compared to reference drugs. The results of this study indicate that the antimicrobial efficacy of the dendrimers is dependent on the size of the redox-active organoiron dendrimer and its terminal functionalities. The best result has been recorded for the fourth-generation dendrimer 11, which attached to 48 paracetamol end groups and has 90 units composed of the &eta, 6-aryl-&eta, 5-cyclopentadienyliron (II) complex. This dendrimer presented inhibition of 50% of the growth (IC50) of 0.52 &mu, M for MRSA, 1.02 &mu, M for VRE, and 0.73 &mu, M for Staphylococcus warneri. The structures of the dendrimers were characterized by elemental analysis, Fourier transform infrared (FT-IR), nuclear magnetic resonance (1H-NMR), and 13C-NMR spectroscopic techniques. In addition, all synthesized dendrimers displayed good thermal stability in the range of 300&ndash, 350 &deg, C following the degradation of the cationic iron moieties which occurred around 200 &deg, C.

The synthesis of a novel and attractive class of nonsteroidal anti-inflammatory and antimicrobial organoiron dendrimers attached to the well-known drug ibuprofen is achieved. The structures of these dendrimers are established by spectroscopic and analytical techniques. The antimicrobial activity of these dendrimers is investigated and tested against five human pathogenic Gram-positive and Gram-negative bacteria, and minimum inhibitory concentrations are reported. Some of these synthesized dendrimers exhibit higher inhibitory activity against methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and Staphylococcus warneri compare to the reference drugs. As well, the in vitro and in vivo anti-inflammatory activities of these dendrimers are evaluated. The results of in vivo anti-inflammatory activity and histopathology of inflamed paws show that all dendrimers display considerable anti-inflammatory activity; however, second-generation dendrimer (G2-D6) shows the best anti-inflammatory activity, which is more potent than the commercial drug ibuprofen at the same tested dose. Results of the toxicity study reveal that G2-D6 is the safest drug on biological tissues.

A series of novel fluorescent 5,7-dihydroxy-4-propyl-2H-chromen-2-one derivatives (2a–j) were synthesized and were found to absorb around 322 and 410 nm.All compounds except the nitro-containing compound exhibited emission wavelengths around 450 nm with good fluorescence quantum yields (ΦF). Their antimicrobial activity was investigated and tested against several human pathogen Gram-positive, Gram-negative bacteria and fungi as well as mycobacterium using agar well diffusion method and minimum inhibitory concentrations were reported. All compounds showed significantly potent antimicrobial activities against most bacterial strains compared to reference drugs. Due to their structural similarity to reference drugs clorobiocin and novobiocin, the docking experiments in the ATP binding pocket of DNA gyrase B enzyme revealed that the compounds mostly have the same binding mode as the reference drugs. Moreover, the cytotoxic activity was also evaluated against four different human cell lines and exhibited more potency than the reference drug.

Star-shaped macromolecules decorated with fluorescence moieties such as pyrene and anthracene have been developed, which exhibit aggregation enhanced excimer emission (AEEE). The presented star-shaped macromolecules showed only weak emissions in the visible region in dilute solution, due to the predominance of the monomer emission, which has its maximum in the UV-A region of the spectrum. However, the strong blue visible excimer-like emission is generated in the aggregated state, by the use of poorly solubilizing solvents or high concentration. The solution of these macromolecules emitted blue light centred at 475 and 474 nm with pyrene and anthracene moieties respectively. In addition, emission efficiency increases were observed with increasing water fraction. The unique phenomenon of AEEE was verified by determining the excimer-monomer emission intensities ratio (IE/IM). TEM was used to detect the difference between the aggregation states in various THF/water ratios. The molecular structures of the fluorescent star were investigated using (MMFF).

Fluorescence dendrimers have been developed, which exhibit aggregation enhanced excimer emission (AEEE). In this article, the synthesis and characterization of three generations of organoiron dendrimers with a flexible core is described. Different photoactive pyrene moieties with and without alkyl chains were used to functionalize the dendritic peripheries. The luminescence properties of these dendrimers were examined in various solvents and concentrations as well as in THF/water mixtures. It was determined that the alkyl chain attached to pyrene moieties had a significant impact on the emission wavelength. Interestingly, dendrimers exhibited weak emission when dissolved in organic solvents but strong emission when aggregated in mixed organic/aqueous solvents. Different emission behaviour was observed in the case of second generation dendrimers, due to the presence of a high number of pyrene moieties. The solution emitted much bluer light relative to the zero and first generations, which emitted around 480 nm. In addition, the change in the distance between two pyrene moieties affects the formation of strong or weak excimers. The excimer–monomer intensity ratios (IE/IM) showed the existence of the unique phenomenon of AEEE. The large difference between the aggregated molecules in various THF/water ratios was detected by TEM. Redox activities of the dendrimers were also measured. A single redox wave was displayed in all dendrimers and the intensity of the redox waves increased by increasing the dendrimer generation. All dendrimers possessed good thermal stability and were shown to have two thermal degradation processes.