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AbstractNew methods of creation of cyclic bridging and terminal exopolyhedral sulfur-containing substituents in the closo-decaborate anion have been suggested. It has been shown that the reaction of [B10H9SH]2– with 1,2-dibromoethane leads to crosslinking of two cluster anions to give the [B10H9S(CH2)4SB10H9]2– dimer. An analogous reaction with 1,4-dibromobutane yields a derivative with the cyclic tetrahydrothiophene substituent [B10H9S(CH2)4]–. Its interaction with tetrahydrothiophene in the presence of a small excess of trifluoroacetic acid leads to the formation of the neutral disubstituted derivative [B10H8(S(CH2)4)2].

The interaction of the [B10H10]2– and [B12H12]2– anions with aliphatic and aromatic nitro compounds (RNO2, where R = Et, n-Pr, i-Pr, tert-Bu, Ph) has been studied under irradiation with visible and UV light. It has been shown that, depending on the reaction conditions, both mono- and disubstituted nitro-closo-decaborates can be selectively obtained in yields up to 50%.

Cobalt(II) complexation with azaheterocyclic ligands L (L = 2,2'-bipyridyl, 1,10-phenanthroline, and 2,2'-bipyridylamine) in the presence of a monohydroxy-substituted derivative of the closo -dodecaborate anion [B 12 H 11 OH] 2– has been studied. Depending on the nature of the organic ligand and the synthesis conditions, coordination compounds [Co III (Bipy) 2 Cl 2 ] 2 [B 12 H 11 OH], [Co II (Phen) 3 ][B 12 H 11 OH] and [Co II (Bipy) 3 ][B 12 H 11 OH] with the boron cluster anion as a counterion, as well as the mixed-ligand complex [Co II (BPA) 2 Cl 2 ] of a known structure, have been isolated and characterized by X-ray diffraction. For the first time, a redox reaction leading to the formation of a cobalt(III) complex in air has been observed for a system containing cobalt(II) and a substituted derivative of the boron cluster anion without the introduction of additional oxidizing agents.

Based on the substituted derivative of the decahydro- closo -decaborate anion (Ph 4 P) 2 [B 10 H 9 O(CH 2 ) 5 COOH] obtained by opening the tetrahydropyran substituent in the anion [B 10 H 9 O(CH 2 ) 5 ] – , compounds of the general formula Na 2 [B 10 H 9 O(CH 2 ) 6 C(O)X], where X = Trp-OMe ( 1 ), His-OMe ( 2 ), Met-OMe ( 3 ), Pld-OMe ( 4 ), containing various amino acid substituents attached to the pendant carboxyl group, were synthesized. The compounds were isolated as sodium salts. The residues of L-tryptophan (Na 2 1 ) and L-histidine (Na 2 2 ) contained aromatic heterocyclic groups indole and imidazole, respectively, as a side group. In turn, compounds Na 2 3 and Na 2 4 contained substituted alkanes as a side group: L-methionine (Na 2 3 ) contained a methyl ethyl sulfide group, and compound Na 2 4 contained the residue of an aliphatic synthetic amino acid, in which the side group was represented by γ-butyrolactam (2-oxopyrrolidin-3-yl) (Pld-OMe). Compounds Na 2 1 and Na 2 2 were found to exhibit dose-dependent antiviral activity against the influenza virus strain A/IIV-Orenburg/83/2012(H1N1)pdm09 in vitro. IC 50 for compound Na 2 1 was found to be 5.0 μg/mL, and for compound Na 2 2 it was found to be 10.0 μg/mL. Molecular docking of the M2 protein pore and ligands 1 and 2 was performed. It was found that the most probable arrangement of molecules in the pore of the M2 channel is associated with the location of the heterocycle inside the pore of the M2 channel in the region of the residues His37–Trp41, with the arrangement being more favorable for 1 rather than for 2 . This fact explains some difference in the concentrations of suppression of viral reproduction for Na 2 1 and Na 2 2 . For compounds Na 2 3 and Na 2 4 , antiviral activity was not detected.

In this work, we studied lead(II) and cobalt(II) complexation of derivatives [2-B10H9O(CH2)2O(CH2)2N3]2− and [2-B10H9O(CH2)5N3]2− of the closo-decaborate anion containing pendant azido groups in the presence of 1,10-phenanthroline and 2,2′-bipyridyl. Mononuclear [PbL2An] and binuclear [Pb2L4(NO3)2An] lead complexes (where An is the N3-substituted boron cluster) were isolated and studied by IR spectroscopy and elemental analysis. The mononuclear lead(II) complex [Pb(phen)2[B10H9O(CH2)2O(CH2)2N3] and the binuclear lead(II) complex [Pb2(phen)4(NO3)2[B10H9O(CH2)5)N3] were determined by single-crystal X-ray diffraction. In complex [Pb2(phen)4(NO3)2[B10H9O(CH2)5)N3], the boron cluster is coordinated by the metal atom only via the 3c2e MHB bonds. In complex [Pb(phen)2[B10H9O(CH2)2O(CH2)2N3], the coordination environment of the metal includes BH groups of the boron cluster and the oxygen atom of the exo-polyhedral substituent. When the reaction was performed in a CH3CN/water mixture, the binuclear lead(II) complex [(Pb(bipy)NO3)(Pb(bipy)2NO3)(B10H9O(CH2)2O(CH2)2N3)]·CH3CN·H2O was isolated, where the boron cluster acts as a bridging ligand between lead atoms coordinated by the boron cage via the O atoms of the substituent and/or the BH groups. In the course of cobalt(II) complexation, the starting compound (Ph4P)2[B10H9O(CH2)5N3] was isolated and its structure was also determined by X-ray diffraction. Although a number of lead(II) complexes with coordinated N3 are known from the literature, no complexes with the boron cluster coordinated by the pendant N3 group involved in the metal coordination have been isolated.

Src kinase-mediated interactions between prostate cancer cells and osteoclasts might promote bone metastasis. Dasatinib inhibits tyrosine kinases, including Src kinases. Data suggests that dasatinib kinase inhibition leads to antitumour activity, affects osteoclasts, and has synergy with docetaxel, a first-line chemotherapy for metastatic castration-resistant prostate cancer. We assessed whether dasatinib plus docetaxel in chemotherapy-naive men with metastatic castration-resistant prostate cancer led to greater efficacy than with docetaxel alone. In this double-blind, randomised, placebo-controlled phase 3 study, we enrolled men of 18 years or older with chemotherapy-naive, metastatic, castration-resistant prostate cancer, and adequate organ function from 186 centres across 25 countries. Eligible patients were randomly assigned (1:1) via an interactive voice response system to receive docetaxel (75 mg/m2 intravenously every 3 weeks, plus oral prednisone 5 mg twice daily), plus either dasatinib (100 mg orally once daily) or placebo until disease progression or unacceptable toxicity. Randomisation was stratified by Eastern Cooperative Oncology Group performance status (0–1 vs 2), bisphosphonate use (yes vs no), and urinary N-telopeptide (uNTx) value (<60 μmol/mol creatinine vs ≥60 μmol/mol creatinine). All patients, investigators, and personnel involved in study conduct and data analyses were blinded to treatment allocation. The primary endpoint was overall survival, analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00744497. Between Oct 30, 2008, and April 11, 2011, 1522 eligible patients were randomly assigned to treatment; 762 patients were assigned to dasatinib and 760 to placebo. At final analysis, median follow-up was 19·0 months (IQR 11·2–25·1) and 914 patients had died. Median overall survival was 21·5 months (95% CI 20·3–22·8) in the dasatinib group and 21·2 months (20·0–23·4) in the placebo group (stratified hazard ratio [HR] 0·99, 95·5% CI 0·87–1·13; p=0·90). The most common grade 3–4 adverse events included diarrhoea (58 [8%] patients in the dasatinib group vs 27 [4%] patients in the placebo group), fatigue (62 [8%] vs 42 [6%]), and asthenia (40 [5%] vs 23 [3%]); grade 3–4 pleural effusions were uncommon (ten [1%] vs three [<1%]). The addition of dasatinib to docetaxel did not improve overall survival for chemotherapy-naive men with metastatic castration-resistant prostate cancer. This study does not support the combination of dasatinib and docetaxel in this population of patients. Bristol-Myers Squibb.

Pharmaceutical pollutants, including ibuprofen, are now ubiquitously detected in global aquatic ecosystems, exerting significant negative ecological impacts. Lake Baikal organisms have been documented to accumulate ibuprofen and related contaminants. This study quantified ibuprofen concentrations within Lake Baikal’s endemic amphipod fauna using high-performance liquid chromatography coupled with mass spectrometry. We analyzed specimens representing key ecological groups across the genera Eulimnogammarus , Brandtia , Ommatogammarus , and Pallasea . Ibuprofen concentrations ranged from 4.19 ng/g to 1,151.32 ng/g (wet weight), confirming consistent contamination in both littoral and deep-water endemic amphipod populations. Crucially, our data provide the first evidence suggesting amphipods, or their associated symbiotic microbiota, may metabolize ibuprofen. Interspecific accumulation patterns were identified, with Eulimnogammarus sp. and Brandtia sp. exhibiting distinct profiles. Furthermore, accumulation was significantly higher during spring compared to autumn samples. A negative correlation emerged between ibuprofen concentration and amphipod body mass within species. Several populations contained non-detectable levels. These findings demonstrate that endemic amphipods within Lake Baikal’s natural environment are exposed to and bioaccumulate the pharmaceutical pollutant ibuprofen, exhibiting species-specific, seasonal, and allometric variation in uptake.

The emergence of drug-resistant influenza virus strains necessitates the development of novel antiviral agents with unique mechanisms of action. This study presents the synthesis and in vitro evaluation of a new class of antiviral compounds: sodium salts of amino acid ester conjugates based on the closo-dodecaborate anion [B12H12]2−, linked via a tetrahydropyran-derived spacer (Na2[B12H11O(CH2)6C(O)X], where X = L-Trp-OMe (Na22); L-His-OMe (Na23); L-Met-OMe (Na24); Pld-OMe (Na25)). The antiviral activity was assessed against contemporary, multidrug-resistant influenza A virus strains, including A/Cheboksary/125/2020 (H1N1)pdm09 and A/IIV-Orenburg/83/2012 (H1N1)pdm09. Cross-platform comparison revealed that the dodecaborate-tryptophan conjugate Na22 exhibited comparable efficacy to its lead decaborate analog against the Orenburg strain while demonstrating potent activity (IC50 = 5.0 µg/mL) against the Cheboksary strain with reduced susceptibility to neuraminidase inhibitors (oseltamivir; zanamivir) and complete resistance to M2 channel blockers. The histidine-based conjugate Na23 also showed significant efficacy against the Cheboksary strain, while methionine and lactam derivatives (Na24; Na25) remained inactive. This work confirms boron clusters as versatile platforms for antiviral development and establishes structure–activity relationships crucial for optimizing both B10 and B12-based therapeutics against resistant influenza strains.

We report the results of a search for a new vector boson (A′) decaying into two dark matter particles χ1χ2 of different mass. The heavier χ2 particle subsequently decays to χ1 and an off-shell Dark Photon A′∗→e+e-. For a sufficiently large mass splitting, this model can explain in terms of new physics the recently confirmed discrepancy observed in the muon anomalous magnetic moment at Fermilab. Remarkably, it also predicts the observed yield of thermal dark matter relic abundance. A detailed Monte-Carlo simulation was used to determine the signal yield and detection efficiency for this channel in the NA64 setup. The results were obtained re-analyzing the previous NA64 searches for an invisible decay A′→χχ¯ and axion-like or pseudo-scalar particles a→γγ. With this method, we exclude a significant portion of the parameter space justifying the muon g-2 anomaly and being compatible with the observed dark matter relic density for A′ masses from 2me up to 390 MeV and mixing parameter ε between 3×10-5 and 2×10-2.

The article presents the results of developing a fragment of a thermal displacement control system, writing the corresponding software for measuring the linear displacement of the monitored equipment and pipelines, and analyzing the obtained results for assessing the technical state and cyclic strength of the monitored equipment as a means of managing the resource characteristics of the controlled object. The measurement uncertainty was evaluated. Taking into account the influence of various factors, such as illumination, the degree of filling the image with the target, the distance from the video camera to the target, as well as the direction and dimensions of displacements and vibration, the volume of test checks was formed using 780 tests. In the course of the analysis, the relative error in measuring displacements taking vibrations into account was revealed to be no more than 5%.