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The reaction of Ag + with Ru 3 (CO) 12 in a CO atmosphere under concommittant irradiation with UV-light yields a salt of the metal-only Lewis-pair [Ag{Ru(CO) 5 } 2 ] + . Switching the silver cation for a more process-selective deelectronator yields a salt of the homoleptic transition metal carbonyl cation [Ru 2 (CO) 10 ] 2+ , which fills the gap between the known cations [Ru(CO) 6 ] 2+ and [Ru 3 (CO) 14 ] 2+ . The amount of π-backdonation in this series was studied by a combination of vibrational spectroscopy and computed relaxed force constants.

We report the synthesis and full characterization of the copper dinitrogen complex [(η 1 -N 2 )Cu{Al(OR F ) 4 }] 2 (R F =C(CF 3 ) 3 ) prepared by a cascade metathesis reaction of Ag[Al(OR F ) 4 ] with CuI-excess in iso-perfluorohexane (i-pfh) under N 2 atmosphere. Title compound 2 features an extraordinarily high N 2 stretching frequency at 2313/2314 cm -1 (IR/Raman) and was characterized by single-crystal and powder X-ray diffractometry. Quantum chemical charge displacement analysis based on natural orbitals of chemical valence (CD-NOCV) indicates that the copper-dinitrogen interaction is still governed by weak π-backdonation, but is significantly reduced compared to all literature-known transition metal dinitrogen complexes., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

A selective deelectronation reagent with very high potential of +2.00 (solution)/+2.41 V (solid-state) vs. Fc +/0 and based on a room temperature stable perfluoronaphthalene (naphthalene F ) radical cation salt was developed and applied. The solid-state deelectronation of commercial naphthalene F with [NO] + [F{Al(OR F ) 3 } 2 ] - generates [naphthalene F ] + ⋅[F{Al(OR F ) 3 } 2 ] - (OR F =OC(CF 3 ) 3 ) in gram scale. Thermochemical analysis unravels the solid-state deelectronation potential of the starting [NO] + -reagent to be +2.34 V vs. Fc +/0 with [F{Al(OR F ) 3 } 2 ] - counterion, but only +1.14 V vs. Fc +/0 with the small [SbF 6 ] - ion. Selective reactions demonstrate the selectivity of [naphthalene F ] + ⋅ for deelectronation of a multitude of organ(ometall)ic molecules and elements in solution: providing the molecular structures of the acene dications [tetracene] 2+ , [pentacene] 2+ or spectroscopic evidence for the carbonyl complex of the ferrocene dication [Fc(CO)] 2+ , the [P 9 ] + cation from white phosphorus, the solvent-free copper(I) salt starting from copper metal and the dicationic Fe(IV)-scorpionate complex [Fe(sc) 2 ] 2+ ., (© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

While the development of weakly coordinating anions (WCAs) received much attention, the progress on weakly coordinating and inert solvents almost stagnated. Here we study the effect of strategic F-substitution on the solvent properties of fluorobenzenes C 6 F x H 6-x (xFB, x = 1-5). Asymmetric fluorination leads to dielectric constants as high as 22.1 for 3FB that exceeds acetone (20.7). Combined with the WCAs [Al(OR F ) 4 ] - or [( F RO) 3 Al-F-Al(OR F ) 3 ] - (R F  = C(CF 3 ) 3 ), the xFB solvents push the potentials of Ag + and NO + ions to +1.50/+1.52 V vs. Fc + /Fc. The xFB/WCA-system has electrochemical xFB stability windows that exceed 5 V for all xFBs with positive upper limits between +1.82 V (1FB) and +2.67 V (5FB) vs. Fc + /Fc. High-level ab initio calculations with inclusion of solvation energies show that these high potentials result from weak interactions of the ions with solvent and counterion. To access the available positive xFB potential range with stable reagents, the innocent deelectronator salts [anthracene F ] +∙ [WCA] - and [phenanthrene F ] +∙ [WCA] - with potentials of +1.47 and +1.89 V vs. Fc + /Fc are introduced., (© 2024. The Author(s).)

ConspectusCarbon monoxide, CO, is one of the most important ligands in organometallic chemistry. It is an excellent π-acceptor and a moderate σ-donor. Therefore, most of the known transition metal carbonyls (TMCs) exhibit a zerovalent or even negative metal oxidation state (OS) of up to -4. However, given the right conditions, the carbonyl ligand also forms homoleptic cationic complexes with one or more transition metal atoms, the transition metal carbonyl cations (TMCCs), known with an OS of up to +3. Despite their long-standing history upon discovery of the first [M(CO) 6 ] + examples (M = Mn, Tc, Re) by E. O. Fischer in 1962 as well as their very fundamental nature, it took until the 1990s for the scope to be widened by Aubke, Strauss and Willner. Yet, many potential TMCC entries known from gas-phase mass spectrometry work remained unknown on preparative grounds. This is due to their high reactivity, which puts scientists to new challenges and encourages the development of suitable solvents, anions and oxidants, to cope with the demands of these fundamental salts─later referred to as pseudo-gas-phase conditions and innocent deelectronators and solvents .Hence, the utilization of extremely weakly coordinating perfluorinated alkoxyaluminates [Al(OR F ) 4 ] - and [F{Al(OR F ) 3 } 2 ] - (OR F = -OC(CF 3 ) 3 ) in combination with the polar but non- or weakly coordinating innocent solvents 1,2-difluorobenzene ( o DFB) and 1,2,3,4-tetrafluorobenzene (TFB) yielded the first TMCC salts containing heptacoordinate [M(CO) 7 ] + (M = Nb, Ta) as well as paramagnetic [M(CO) 6 ] +· (M = Cr, Mo, W) or [Ni(CO) 4 ] +· . However, the use of typical inorganic oxidants Ag + , [NO] + and Ag + /0.5 I 2 regularly led to unwanted side reactions. For example, the Lewis acidic silver(I) cations form Lewis pairs with various Lewis basic TMCs yielding partly clustered [Ag x {TMC} y ] x + complex salts, while nitrosonium cations may substitute for carbonyl ligands, forming [M(CO) x -1 (NO)] + complexes. The synergistic oxidizing reagent Ag + /0.5 X 2 can add halonium ions X + to the TMCs (X = Cl, Br, I). This prevented the synthesis of univalent group 8 TMCC salts. Yet, the application of radical cation salts of perfluorinated arenes as innocent deelectronators finally yielded salts of [Fe(CO) 5 ] +· and [M 3 (CO) 14 ] 2+ (M = Ru, Os).TMCC salts are excellent starting materials, and the reaction of [Co(CO) 5 ] + and [Ni(CO) 4 ] +· with benzene led to the previously unknown bis(benzene) sandwich complexes [Co(benzene) 2 ] + and [Ni(benzene) 2 ] +· . Under the right conditions, even the very weakly bound o DFB-complex salts with [M( o DFB) 2 ] + (M = Co, Ni) cations form, useful as naked metal(I) synthons and for small-molecule activation.

The unsubstituted acenium radical cations (ARCs) are extremely sensitive and were hitherto only studied in situ, i. e. in the gas phase, as dilute solutions in strong acids or by matrix isolation spectroscopy at about 10 K. In this study, room temperature stable ARC salts with the weakly coordinating anion [F{Al(OR F ) 3 } 2 ] - (OR F =-OC(CF 3 ) 3 ) supported by the weakly coordinating solvent 1,2,3,4-tetrafluorobenzene (TFB) were prepared and structurally, electrochemically and spectroscopically characterized. Reaction of the neutral acenes with Ag + [F{Al(OR F ) 3 } 2 ] - led, non-innocent, [54] to intermediate [Ag 2 (acene) 2 ] 2+ complexes, which decompose over time to Ag 0 and the corresponding (impure) ARC salts. By contrast, direct deelectronation with the recently developed innocent [54] deelectronator radical cation salt [anthracene Hal ] +⋅ [F{Al(OR F ) 3 } 2 ] - led to phase-pure products [acene] +⋅ [F{Al(OR F ) 3 } 2 ] - (anthracene Hal =9,10-dichlorooctafluoroanthracene; acene=anthra-, tetra-, pentacene). For the first time, a homogenous set of spectroscopic data on analytically pure ARC salts was obtained. In addition, cyclovoltammetric measurements of the acenes connected the potentials in solution with those in the gas-phase. Hence, the data complement the existing isolated gas-phase, strong acid or matrix isolation studies. A first entry to follow-up chemistry of the acenium radical cations as ligand forming oxidizers was demonstrated by reaction with 1 / 2 ${{ 1/2 }}$ Co 2 (CO) 8 giving [Co(anthracene)(CO) 2 ] + ., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

The title silver(I) complex salts [Ag{Re 2 (CO) 10 }{Re(CO) 5 } 2 ] + [Al(OR F ) 4 ] - (AgRe 4 ; OR F =-OC(CF 3 ) 3 ) and [Ag{Ir 4 (CO) 12 } 2 ] + [Al(OR F ) 4 ] - (AgIr 8 ) form upon reaction of Ag + [Al(OR F ) 4 ] - and the transition metal carbonyls (TMCs) Re 2 (CO) 10 and Ir 4 (CO) 12 respectively. The solid-state structure of the AgRe 4 cluster shows an unexpected asymmetric coordination motif, wherein the silver(I) cation has inserted into the Re-Re bond of one Re 2 (CO) 10 moiety, while the other dirhenium carbonyl coordinates only over one metal atom towards the silver(I) cation. The AgIr 8 cluster is formed by the edge-on coordination of two Ir 4 tetrahedra and the silver cation in a D 2 symmetric fashion with a torsion angle of 46.5°. QTAIM analysis shows bond paths between the silver atom and the nearby metal atoms in all cases, whereas only the non-inserted Re 2 (CO) 10 moiety shows additional bond paths between the carbonyl ligands and the silver cation. In addition, the insertion of the Ag + cation into the Re-Re bond in Re 2 (CO) 10 removes the bond path between the two rhenium atoms. The EDA-NOCV analysis suggests an increase of the interaction energy between the silver(I) cation and the respective metal carbonyls from the metal centered transition metal carbonyl (TMC) donors W(CO) 6 2 (CO) 10 3 (CO) 12 4 (CO) 12 . In all cases, the dominating orbital interaction is σ-donation [TMC]→Ag + ←[TMC]., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

The reaction of AgBF 4 and [Rh(COD)Cl] 2 (COD=1,5-cyclooctadiene) in presence of [NEt 4 ][C 5 (CF 3 ) 5 ] afforded the fluorocarbon soluble complex [Rh(COD)(C 5 (CF 3 ) 5 )] by salt metathesis. This complex represents the first example for a successful coordination of the weakly basic [C 5 (CF 3 ) 5 ] - ligand, since its first synthesis in 1980. In addition to [Rh(COD)(C 5 (CF 3 ) 5 )] also the byproduct [Rh(COD)(C 5 (CF 3 ) 4 H)] was isolated and fully characterized. Accompanying DFT studies showed that the interaction energy of the [C 5 (CF 3 ) 5 ] - ligand towards the 12-electron fragment [Rh(COD)] + is ≈70 kcal mol -1 lower in comparison to [C 5 (CH 3 ) 5 ] - due to reduced electrostatic interactions and weaker π-donor properties of the ligand. The quantitative but reversible substitution of the [C 5 (CF 3 ) 5 ] - ligand by toluene, converting it into a weakly coordinating anion, experimentally proved the extraordinary weak bonding interaction., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Multiple myeloma (MM) treatment regimens have vastly improved since the introduction of immunomodulators, proteasome inhibitors, and anti-CD38 monoclonal antibodies; however, MM is considered an incurable disease due to inevitable relapse and acquired drug resistance. Understanding the molecular mechanism by which drug resistance is acquired will help create novel strategies to prevent relapse and help develop novel therapeutics to treat relapsed/refractory (RR)-MM patients. Currently, only homozygous deletion/mutation of TP53 gene due to "double-hits" on Chromosome 17p region is consistently associated with a poor prognosis. The exciting discovery of XPO1 overexpression and mislocalization of its cargos in the RR-MM cells has led to a novel treatment options. Clinical studies have demonstrated that the XPO1 inhibitor selinexor can restore sensitivity of RR-MM to PIs and dexamethasone. We will elaborate on the problems of MM treatment strategies and discuss the mechanism and challenges of using XPO1 inhibitors in RR-MM therapies while deliberating potential solutions., (Copyright © 2022. Published by Elsevier Inc.)

To access the hitherto almost unknown class of clustered transition metal carbonyl cations, the trimetal dodecacarbonyls M 3 (CO) 12 (M = Ru, Os) were reacted with the oxidant Ag + [WCA] - , but yielded the silver complexes [Ag{M 3 (CO) 12 } 2 ] + [WCA] - (WCA = [Al(OR F ) 4 ] - , [F{Al(OR F ) 3 } 2 ] - ; R F = -OC(CF 3 ) 3 ). Addition of further diiodine I 2 to increase the redox potential led for M = Ru non-specifically to divalent mixed iodo-Ru II -carbonyl cations. With [NO] + , even the N-O bond was cleaved and led to the butterfly carbonyl complex cation [Ru 4 N(CO) 13 ] + in low yield. Obviously, ionization of M 3 (CO) 12 with retention of its pseudo-binary composition including only M and CO is difficult and the inorganic reagents did react non-innocently. Yet, the radical cation of the commercially available perhalogenated anthracene derivative 9,10-dichlorooctafluoroanthracene (anthracene Hal ) is a straightforward accessible innocent deelectronator with a half-wave potential E 1/2 of 1.42 V vs. . It deelectronates M 0/+ . It deelectronates M 3 under a CO atmosphere and leads to the structurally characterized cluster salts [M 12 under a CO atmosphere and leads to the structurally characterized cluster salts [M 3 (CO) 14 ] 2+ ([WCA] - including a linear M 2 chain. The structural characterization as well as vibrational and NMR spectroscopies indicate the presence of three electronically independent sets of carbonyl ligands, which almost mimic M(CO) 3 , free CO and even [M(CO) 5 , free CO and even [M(CO) 6 ] 2+ in one and the same cation., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Our understanding of MM genomics has expanded rapidly in the past 5-10 years as a consequence of cytogenetic analyses obtained in routine clinical practice as well as the ability to perform whole-exome/genome sequencing and gene expression profiling on large patient data sets. This knowledge has offered new insights into disease biology and is increasingly defining high-risk genomic patterns. In this manuscript, we present a thorough review of our current knowledge of MM genomics. The epidemiology and biology of chromosomal abnormalities including both copy number abnormalities and chromosomal translocation are described in full with a focus on those most clinically impactful such as 1q amplification and del(17p) as well as certain chromosome 14 translocations. A review of our ever-expanding knowledge of genetic mutations derived from recent whole-genome/exome data sets is then reviewed including those that drive disease pathogenesis from precursor states as well as those that may impact clinical outcomes. We then transition and attempt to elucidate how both chromosomal abnormalities and gene mutations are evolving our understanding of disease risk. We conclude by offering our perspectives moving forward as to how we might apply whole-genome/exome-level data in addition to routine cytogenetic analyses to improve patient outcomes as well as further knowledge gaps that must be addressed., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Splice modulators have been assessed clinically in treating haematologic malignancies exhibiting splice factor mutations and acute myeloid leukaemia. However, the mechanisms by which such modulators repress leukaemia remain to be elucidated., Objectives: The primary goal of this assessment was to assess the molecular mechanism by which the natural splice modulator GEX1A kills leukaemic cells in vitro and within in vivo mouse models., Methods: Using human leukaemic cell lines, we assessed the overall sensitivity these cells have to GEX1A via EC 50 analysis. We subsequently analysed its effects using in vivo xenograft mouse models and examined whether cell sensitivities were correlated to genetic characteristics or protein expression levels. We also utilised RT-PCR and RNAseq analyses to determine splice change and RNA expression level differences between sensitive and resistant leukaemic cell lines., Results: We found that, in vitro, GEX1A induced an MCL-1 isoform shift to pro-apoptotic MCL-1S in all leukaemic cell types, though sensitivity to GEX1A-induced apoptosis was negatively associated with BCL-xL expression. In BCL-2-expressing leukaemic cells, GEX1A induced BCL-2-dependent apoptosis by converting pro-survival BCL-2 into a cell killer. Thus, GEX1A + selective BCL-xL inhibition induced synergism in killing leukaemic cells, while GEX1A + BCL-2 inhibition showed antagonism in BCL-2-expressing leukaemic cells. In addition, GEX1A sensitised FLT3-ITD + leukaemic cells to apoptosis by inducing aberrant splicing and repressing the expression of FLT3-ITD. Consistently, in in vivo xenografts, GEX1A killed the bulk of leukaemic cells via apoptosis when combined with BCL-xL inhibition. Furthermore, GEX1A repressed leukaemia development by targeting leukaemia stem cells through inhibiting FASTK mitochondrial isoform expression across sensitive and non-sensitive leukaemia types., Conclusion: Our study suggests that GEX1A is a potent anti-leukaemic agent in combination with BCL-xL inhibitors, which targets leukaemic blasts and leukaemia stem cells through distinct mechanisms., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Receptor-interacting protein kinase 3 (Ripk3) is one of the critical mediators of inflammatory cytokine-stimulated signaling. Here we show that Ripk3 signaling selectively regulates both the number and the function of hematopoietic stem cells (HSCs) during stress conditions. Ripk3 signaling is not required for normal homeostatic hematopoiesis. However, in response to serial transplantation, inactivation of Ripk3 signaling prevents stress-induced HSC exhaustion and functional HSC attenuation, while in response to fractionated low doses of ionizing radiation (IR), inactivation of Ripk3 signaling accelerates leukemia/lymphoma development. In both situations, Ripk3 signaling is primarily stimulated by tumor necrosis factor-α. Activated Ripk3 signaling promotes the elimination of HSCs during serial transplantation and pre-leukemia stem cells (pre-LSCs) during fractionated IR by inducing Mlkl-dependent necroptosis. Activated Ripk3 signaling also attenuates HSC functioning and represses a pre-LSC-to-LSC transformation by promoting Mlkl-independent senescence. Furthermore, we demonstrate that Ripk3 signaling induces senescence in HSCs and pre-LSCs by attenuating ISR-mediated mitochondrial quality control., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

The oxidation power of the cyanocarbon TCNQ (tetracyano-quinodimethane) can be significantly increased to approximately E = +0.9 V vs. Cp 2 Fe by coordination of up to four equivalents of the strong fluorinated Lewis acid B(C 6 F 5 ) 3 , resulting in a highly reactive but easy-to-use oxidation system. Thianthrene and tris(4-bromophenyl)amine were oxidized to the corresponding radical cations. Dianionic [TCNQ·4 B(C 6 F 5 ) 3 ] 2- was formed upon reduction with two equivalents of ferrocene or decamethylcobaltocene. [TCNQ·4 B(C 6 F 5 ) 3 ] - and [TCNQ·4 B(C 6 F 5 ) 3 ] 2- are rare cases of redox-active weakly-coordinating anions.

The pharyngeal mucosa can be colonized with bacteria that have potential to cause pharyngotonsillitis. By the use of culturing techniques and PCR, we aimed to assess the prevalence of bacterial pharyngeal pathogens among healthy adolescents and young adults. We performed a cross-sectional study in a community-based cohort of 217 healthy individuals between 16 and 25 years of age. Samples were analyzed for Group A streptococci (GAS), Group C/G streptococci (SDSE), Fusobacterium necrophorum, and Arcanobacterium haemolyticum. Compared to culturing, the PCR method resulted in more frequent detection, albeit in most cases with low levels of DNA, of GAS (20/217 vs. 5/217; p < 0.01) and F. necrophorum (20/217 vs. 8/217; p < 0.01). Culturing and PCR yielded similar rates of SDSE detection (14/217 vs. 12/217; p = 0.73). Arcanobacterium haemolyticum was rarely detected (3/217), and only by PCR. Overall, in 25.3% (55/217) of these healthy adolescents and young adults at least one of these pathogens was detected, a rate that is higher than previously described. Further studies are needed before clinical adoption of PCR-based detection methods for pharyngeal bacterial pathogens, as our findings suggest a high incidence of asymptomatic carriage among adolescents and young adults without throat infections., (© 2021 The Authors. APMIS published by John Wiley & Sons Ltd on behalf of Scandinavian Societies for Medical Microbiology and Pathology.)