Genes crucial for cancer development can be mutated via various mechanisms, which may reflect the nature of the mutagen. In thyroid papillary carcinomas, mutations of genes coding for effectors along the MAPK pathway are central for transformation. BRAF point mutation is most common in sporadic tumors. By contrast, radiation-induced tumors are associated with paracentric inversions activating the receptor tyrosine kinases RET and NTRK1. We report here a rearrangement of BRAF via paracentric inversion of chromosome 7q resulting in an in-frame fusion between exons 1-8 of the AKAP9 gene and exons 9-18 of BRAF. The fusion protein contains the protein kinase domain and lacks the autoinhibitory N-terminal portion of BRAF. It has elevated kinase activity and transforms NIH3T3 cells, which provides evidence, for the first time to our knowledge, of in vivo activation of an intracellular effector along the MAPK pathway by recombination. The AKAP9-BRAF fusion was preferentially found in radiation-induced papillary carcinomas developing after a short latency, whereas BRAF point mutations were absent in this group. These data indicate that in thyroid cancer, radiation activates components of the MAPK pathway primarily through chromosomal paracentric inversions, whereas in sporadic forms of the disease, effectors along the same pathway are activated predominantly by point mutations.

The assembly of spherical fullerenes, or buckyballs, into single crystals for crystallographic identification often suffers from disordered arrangement. Here we show a chiral configuration of decapyrrylcorannulene that has a concave ‘palm’ of corannulene and ten flexible electron-rich pyrryl group ‘fingers’ to mimic the smart molecular ‘hands’ for self-adaptably cradling various buckyballs in a (+)hand-ball-hand(−) mode. As exemplified by crystallographic identification of 15 buckyball structures representing pristine, exohedral, endohedral, dimeric and hetero-derivatization, the pyrryl groups twist with varying dihedral angles to adjust the interaction between decapyrrylcorannulene and fullerene. The self-adaptable electron-rich pyrryl groups, susceptible to methylation, are theoretically revealed to contribute more than the bowl-shaped palm of the corannulene in holding buckyball structures. The generality of the present decapyrrylcorannulene host with flexible pyrryl groups facilitates the visualization of numerous unknown/unsolved fullerenes by crystallography and the assembly of the otherwise close-packed spherical fullerenes into two-dimensional layered structures by intercalation.

Carboncones, a special family of all-carbon allotropes, are predicted to have unique properties that distinguish them from fullerenes, carbon nanotubes, and graphenes. Owing to the absence of methods to synthesize atomically well-defined carboncones, however, experimental insight into the nature of pure carboncones has been inaccessible. Herein, we describe a facile synthesis of an atomically well-defined carboncone[1,2] (C70H20) and its soluble penta-mesityl derivative. Identified by x-ray crystallography, the carbon skeleton is a carboncone with the largest possible apex angle. Much of the structural strain is overcome in the final step of converting the bowl-shaped precursor into the rigid carboncone under mild reaction conditions. This work provides a research opportunity for investigations of atomically precise single-layered carboncones having even higher cone walls and/or smaller apex angles.

The development of biomimetic chemistry based on the NAD(P)H with hydrogen gas as terminal reductant is a long‐standing challenge. Through rational design of the chiral and regenerable NAD(P)H analogues based on planar‐chiral ferrocene, a biomimetic asymmetric reduction has been realized using bench‐stable Lewis acids as transfer catalysts. A broad set of alkenes and imines could be reduced with up to 98 % yield and 98 % ee, likely enabled by enzyme‐like cooperative bifunctional activation. This reaction represents the first general biomimetic asymmetric reduction (BMAR) process enabled by chiral and regenerable NAD(P)H analogues. This concept demonstrates catalytic utility of a chiral coenzyme NAD(P)H in asymmetric catalysis.

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The coenzyme NAD(P)H plays an important role in electron as well as proton transmission in the cell. Thus, a variety of NAD(P)H models have been involved in biomimetic reduction, such as stoichiometric Hantzsch esters and achiral regenerable dihydrophenantheridine. However, the development of a general and new-generation biomimetic asymmetric reduction is still a long-term challenge. Herein, a series of chiral and regenerable NAD(P)H models with central, axial, and planar chiralities have been designed and applied in biomimetic asymmetric reduction using hydrogen gas as a terminal reductant. Combining chiral NAD(P)H models with achiral transfer catalysts such as Brønsted acids and Lewis acids, the substrate scope could be also expanded to imines, heteroaromatics, and electron-deficient tetrasubstituted alkenes with up to 99% yield and 99% enantiomeric excess (ee). The mechanism of chiral regenerable NAD(P)H models was investigated as well. Isotope-labeling reactions indicated that chiral NAD(P)H models were regenerated by the ruthenium complex under hydrogen gas first, and then the hydride of NAD(P)H models was transferred to unsaturated bonds in the presence of transfer catalysts. In addition, density functional theory calculations were also carried out to give further insight into the transition states for the corresponding transfer catalysts.

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Molecular cages have attracted great attention because of their fascinating topological structures and well‐defined functional cavities. These discrete cages were usually fabricated by coordination assembly approach, a process employing directional metal‐ligand coordination bonds due to the nature of the divinable coordination geometry and the required lability to encode dynamic equilibrium/error‐correction. Compared to these coordination molecular cages with mononulcear metal‐nodes, an increasing number of molecular cages featuring dinuclear and then polynuclear metal‐cluster nodes have been synthesized. These metal‐cluster‐based coordination cages (MCCCs) combine the merits of both metal clusters and the cage structure, and exhibit excellent performances in catalysis, separation, host‐guest chemistry and so on. In this review, we highlight the syntheses of MCCCs and their potential functions that is donated by the metal‐cluster nodes.