Herein, we report two new cationic iridium(III) homodinuclear structures linked through a diyne moiety at the 5-position of the bipyridyl ligand (1,4-di(2,2'-bipyridin-5-yl)buta-1,3-diyne) and compare these to mononuclear model systems bearing a 5-ethynyl-2,2'-bipyridine ligand. Low energy bands observed in the absorption spectra point to charge-transfer transitions for all four complexes, with these bands red-shifted in the case of the two dinuclear complexes. Electrochemical studies show metal-centred oxidation and ligand-centred first reduction potentials. In the case of the dimer bearing 2-phenylpyridine (ppyH) cyclometallating ligands, cyclic voltammetry (CV) measurements reveal two one-electron oxidation waves and a corresponding reduction in the HOMO-LUMO gap (ΔE(red-ox)) compared to a mononuclear system, pointing to a significant electronic coupling between the two iridium(III) metals. The room temperature emission spectrum of this dimer is also bathochromically shifted, corroborating the CV data. In the case of the iridium dimer bearing 2-(2,4-difluorophenyl)-5-methylpyridine (dFMeppy) ligands, only a single one-electron oxidation wave is observed, but with the expected smaller ΔE(red-ox) value, compared to its mononuclear counterpart. The emission spectra at room temperature are generally broad and featureless with only modest quantum efficiencies (Φ(PL) = 1.4-8.4%) in 2-methyltetrahydrofuran (2-MeTHF) solution. All complexes emit at 77 K with lifetimes on the order of 4 μs. A combined density functional theory (DFT) and time-dependent DFT (TDDFT) study reveals that the emission process is best described as a mixed metal-to-ligand/ligand-to-ligand charge transfer (MLCT/LLCT).

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The photophysical properties of [Ir]-[Pt]-[Ir]-[Pt]-[Ir] ([Ir] = [Ir(ppy)(2)(bpy*)](+) ([Pt] = trans-Pt(PBu(3))(2)(C≡C)(2); ppyH = 2-phenylpyridine); bpy* = bipyridyl;) reveal an unprecedented triplet energy transfer from the terminal iridiums to the central Ir subunit.

Here, we synthesized new thiazole complexes from Cu (II), Fe (III), and Pd (II) ions. Such complexes were characterized to present their chemical formulae, firstly. The octahedral geometry was suggested for the investigated complexes except Pd (II) complex (ARPTPd), which has a square‐planer arrangement. ARPTPd was planned to be used as a catalyst for synthesis of dihydrotetrazolo[1,5‐a]pyrimidine derivatives at mild conditions. The catalytic activity of ARPTPd complex in four‐components reaction approach was deliberately monitored till it reaches the most favorable conditions. The advantages of suggested catalyst were basically summarized by using green solvent (H2O), lower reaction time, and high products yields. Also, the superiority of ARPTPd complex and ultrasonic irradiation towards synthesis of dihydrotetrazolo[1,5‐a]pyrimidine derivatives was revealed compared with other Lewis acids, basic, and ionic liquid catalysts. Furthermore, the mildness of conversion and compatibility with different functional groups makes it attractive. In addition, in consecration, computational aspects were often taken according to their effect on the declaration or discrimination of variable functional characteristics. Crystal packing systems of complexes were configured to extract important surface properties. DFT study was also applied to explain the causes behind the superiorly of ARPTPd complex. Also, the optimization process for intermediates was executed to support the suggested mechanism. Finally, this simple, economical, and green catalytic procedure may be applied to the industry in future.

The C≡C-linkage of Pt(PR(3))(2)(C≡CAr)(2) with (C^N)(2)Ir(N^N)(+) (C^N = 2-phenylpyridine; N^N = bipyridyl) leads to hetero-bi- and trimetallic species exhibiting photophysical properties reminiscent of both [Pt]- and [Ir]-containing moieties through the generation of a [Pt] → [Ir] charge transfer excited state.

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Aim In this study, we have examined the individual and combined protective mechanism of probiotic and Bidens pilosa on the performance and gut health of chickens during Eimeria tenella infection over a 29‐day experimental trial. Methods and Results A total of one hundred and fifty 1‐day‐old chickens were equally distributed into five treatment groups with three biological replicates: two groups were allocated as control groups (control group untreated unchallenged, CG and control positive untreated challenged, CPG) and three groups were fed diets with probiotic (PG), B. pilosa (BPG) and probiotic + B. pilosa (PG + BPG) and challenged with E. tenella. Birds of all groups were assessed for pre and post‐infection body weights, oocysts shedding, caecal lesion scores and mRNA expression levels of apoptosis related proteins (Bcl‐2, Bax and caspase‐3), antioxidant enzymes (CAT and SOD 1), pro‐inflammatory cytokines (IL‐6 and IL‐8) and tight junction proteins (CLDN 1 and ZO 1). Our results revealed that during infection (day 21–29), E. tenella challenged chickens significantly decreased the body weight compared with uninfected control chickens; however, there was no significant effect on body weight of chickens fed with probiotic, B. pilosa and probiotic + B. pilosa was observed. Eimeria tenella challenged untreated birds increased (P < 0·05) oocysts shedding, destructive ratio of caeca and mortality as compared to treated challenged birds. CPG group up‐regulated the mRNA expression levels of anti‐apoptosis protein Bcl‐2 while down‐regulated the pro‐apoptosis protein Bax relative to PG, BPG and PG + BPG groups. Moreover chickens fed probiotic, B. pilosa and probiotic + B. pilosa diets enhanced the activities of antioxidant enzymes, pro‐inflammatory cytokines and tight junction proteins with the comparison of control positive untreated challenged chickens. Conclusion These findings elaborated that feed supplementation of probiotic and B. pilosa (individually or in combination) appeared to be effective in inhibiting the occurrence of disease and decreasing the severity of Eimeria infection in chickens. Significance and Impact of the Study This study explained the underlying anti‐coccidial mechanism in which probiotic and B. pilosa (individually and/or in combination) improve the performance of chicken and protect against gut inflammatory responses caused by E. tenella.

This study describes the solvent and catalyst-free Ugi reaction by way of twin screw extrusion (TSE). Multicomponent chemical synthesis can be converted into a single process without repeated use of solvents through TSE. High synthetic yields are achieved in short reaction times and produced in solvent-free conditions, which lead to a more environmentally friendly process.