Three novel dimolybdenum dimers [Mo2(DAniF)3]2(μ-OSCC6H4CSO), [Mo2(DAniF)3]2(μ-O2CC6H4CS2), and [Mo2(DAniF)3]2(μ-S2CC6H4CS2) (DAniF = N,N'-di(p-anisyl)formamidinate) have been synthesized and characterized by single-crystal X-ray diffractions. Together with the terephthalate analogue, the four compounds, denoted as [O2-O2], [OS-OS], [S2-S2], and [O2-S2], have similar molecular skeletons and Mo2···Mo2 separations (∼12 Å), but varying sulfur contents or symmetry. The singly oxidized complexes [O2-O2](+), [OS-OS](+), [S2-S2](+), and [O2-S2](+) display characteristic intervalence transition absorption bands in the near- and mid-IR regions, with differing band energy, intensity, and shape. Applying the geometrical length of the bridging group "-CC6H4C-" (5.8 Å) as the effective electron transfer distance, calculations from the Mulliken-Hush equation yield electronic coupling matrix elements (H(ab)) in the range 600-900 cm(-1). Significantly, this series presents a transition from electron localization to "almost-delocalization" as the carboxylate groups of the bridging ligand are successively thiolated. In terms of Robin-Day's scheme, [S2-S2](+) is best described as an intermediate between Class II and III, while [O2-O2](+) and [OS-OS](+) belong to Class II. It is unusual that the Class II-III transition occurs in such a weakly coupled system (H(ab) < 1000 cm(-1)). This is attributed to the d(δ)-p(π) conjugation between the Mo2 center and bridging ligand. By electrochemical and spectroscopic methods, the internal energy difference for [O2-S2](+) is determined to be 2250 ± 80 cm(-1), which controls the charge distribution of the cation radical. The experimental results and theoretical analyses illustrate that the unsymmetrical geometry leads to unbalanced electronic configurations and asymmetrical redox and optical behaviors.

Mild-mannered: The low-valent aryl gallium(I) species :GaAr' (Ar' = 2,6-(2,6-iPr(2)C(6)H(3))(2)C(6)H(3)) undergoes addition to H(2) or NH(3) at room temperature and one atmosphere of pressure to afford 1 or 2 (see scheme), which were characterized by X-ray crystallography and NMR and IR spectroscopy.

Reactions of the heteroleptic diarylgermylenes GeAr(#)(Ar') (1) or GeAr(#) (Ar*-3,5-Pr(i)(2)) (2) (Ar(#) = C(6)H(3)-2,6-(C(6)H(2)-2,4,6-Me(3))(2); Ar' = C(6)H(3)-2,6-(C(6)H(3)-2,6-Pr(i)(2))(2); Ar*-3,5-Pr(i)(2) = C(6)H-2,6-(C(6)H(2)-2,4,6-Pr(i)(3))(2)-3,5-Pr(i)(2)) with carbon monoxide at room temperature gave alpha-germyloxy ketones via double CO insertion into the Ge-Ar' carbon bond in 1 and the Ge-Ar(#) bond in 2. The Ar(#)Ge-OCC(O)Ar' and 3,5-Pr(i)(2)Ar*Ge-O-CC(O)Ar(#) intermediates that are formed are unstable and rearrange via the insertion of the carbon of the GeOC moiety into a methyl-aryl or isopropyl carbon to form six-membered ring products.

Metal-metal bonding in the dimeric chromium complex [Ar'CrCrAr'] (Ar' = C 6 H 3 -2,6(2,6-iPr 2 C 6 H 3 ) 2 is derived from the interaction of two d 5 {CrAr'} fragments whose valence electrons are paired to form a quintuple bond. [1][2][3][4][5] The ready synthesis [1] of this complex by the simple reduction of an aryl metal halide precursor [6] suggests the possible formation of similar complexes by other transition metals. Such complexes might exhibit unprecedented types of interactions between metals of various d n configurations, and their isolation and characterization would permit informative comparisons with the chromium species. Herein, we report the synthesis, structural and spectroscopic characterization of the iron and cobalt derivatives [Ar'MMAr'] (M = Fe (1) or Co (2)) and clarify that, although they bear a structural resemblance to [Ar'CrCrAr'], their metal-metal bonding has little in common with that of the chromium analogue.Complexes 1 [7b] with the potassium-graphite intercalate KC 8 in tetrahydrofuran. The metal dimers crystallized as very dark red (1) or very dark green (2) solids. They were initially characterized by X-ray crystallography, [8] which revealed that they had a dimeric structure (Figure 1 and Figure 2, respectively; selected structural data are provided in the Figure legends).The overall trans-bent C ipso MMC ipso core configuration is similar to that in [Ar'CrCrAr'].[1] This resemblance is misleading, however, and masks profound differences both in the metal-metal and the metal-ligand interactions. In a manner which appears to be similar to that in [Ar'CrCrAr'], the iron and cobalt atoms are h 1 bonded to an ipso-carbon center from the central aryl ring of the terphenyl ligand and are also h 6 bonded to a flanking ring of a terphenyl ligand attached to the other metal center within the dimer. However, in complexes 1 and 2, these flanking-ring interactions are much stronger than those in [Ar'CrCrAr'], as indicated by the

Myotonic dystrophy type 1 (DM1) is caused by a CTG nucleotide repeat expansion within the 3′ UTR of the Dystrophia Myotonica protein kinase gene. In this study, we explored therapeutic genome editing using CRISPR/Cas9 via targeted deletion of expanded CTG repeats and targeted insertion of polyadenylation signals in the 3′ UTR upstream of the CTG repeats to eliminate toxic RNA CUG repeats. We found paired SpCas9 or SaCas9 guide RNA induced deletion of expanded CTG repeats. However, this approach incurred frequent inversion in both the mutant and normal alleles. In contrast, the insertion of polyadenylation signals in the 3′ UTR upstream of the CTG repeats eliminated toxic RNA CUG repeats, which led to phenotype reversal in differentiated neural stem cells, forebrain neurons, cardiomyocytes, and skeletal muscle myofibers. We concluded that targeted insertion of polyadenylation signals in the 3′ UTR is a viable approach to develop therapeutic genome editing for DM1.