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A hexacationic cage 3 6+ was synthesized via hydrazone condensation in aqueous acid. Cage 3 6+ bears three biscationic arms, each of which contains four relatively acidic protons, including one NH and three CH protons. These hydrogen bond donors, as well as its intrinsic cationic nature, enable cage 3 6+ to encapsulate two anions concurrently within its cavity. The axial asymmetrical nature of the biscationic arms allow the cage to recognize two different anions in a selective manner, to encompass bound heteroanion dimers, such as Cl − •NO3 − and Cl − • Br − . Single crystal X-ray diffraction analyses reveal that in the solid state the two anions are constrained in ultraclose proximity within the cage; e.g., the Cl − •••Cl − and Cl − •••Br − distances are 3.2 and 2.9 Å, respectively, which are shorter than the sum of their van der Waals radii. Evidence consistent with the sequential binding of two identical or disparate anions in CD 3 CN is also presented.

Herein, we report the self-assembly of an anionic homochiral octahedral cage by condensing six Ga 3+ cations and four trisacylhydrazone ligands.T he robust nature of the hydrazone bond renders the cage stable in water,where it can take advantage of the hydrophobic effect for host-guest recognition. In addition to the internal binding site,n amely, the inner cavity,the octahedral cage possesses four "windows", each of which represents an external binding site allowing peripheral complexation. These internal and external binding sites endowthe cage with the capability to bind abroad range of guests whose sizes could either be smaller than or exceed the volume of the cage'si nner cavity.U pon accommodation of ac hiral guest, one of the two cage enantiomers becomes more favored than the other,p roducing circular-dichroism (CD) signals.T he CD signal intensity of the cage is observed to be proportional to the ee value of the chiral guest, allowing aquantitative determination of the latter.

Most crops are sensitive to salt stress, but their degree of susceptibility varies among species and cultivars. In order to understand the salt stress adaptability of Brassica napus to salt stress, we collected the phenotypic data of 505 B. napus accessions at the germination stage under 150 or 215 mM sodium chloride (NaCl) and at the seedling stage under 215 mM NaCl. Genome-wide association studies (GWAS) of 16 salt tolerance coefficients (STCs) were applied to investigate the genetic basis of salt stress tolerance of B. napus. In this study, we mapped 31 salts stress-related QTLs and identified 177 and 228 candidate genes related to salt stress tolerance were detected at germination and seedling stages, respectively. Overexpression of two candidate genes, BnCKX5 and BnERF3 overexpression, were found to increase the sensitivity to salt and mannitol stresses at the germination stage. This study demonstrated that it is a feasible method to dissect the genetic basis of salt stress tolerance at germination and seedling stages in B. napus by GWAS, which provides valuable loci for improving the salt stress tolerance of B. napus. Moreover, these candidate genes are rich genetic resources for the following exploration of molecular mechanisms in adaptation to salt stress in B. napus.

A triangular‐prism shaped cage was self‐assembled by the formation of a dynamic covalent bond, namely a hydrazone, in acidic aqueous solution. The hexacationic host bears a number of relatively acidic protons pointing inside the cage cavity, which is able to accommodate an iodide anion selectively in water over other halide anions such as F−, Cl−, and Br−, which are more hydrated. As a comparison, a macrocycle analogue bearing fewer positive charges and fewer hydrogen bond donors shows no anion binding ability. As inferred from the single‐crystal structure and theoretical calculations, the ability of the cage to selectively recognize iodide anions results from the combination of electrostatic forces, C−H⋅⋅⋅I− hydrogen bonds, and the hydrophobic effect.

A one-pot transition metal-free method for synthesizing benzo[4,5]imidazo[1,2-a]quinazoline and imidazo[1,2-a]quinazoline derivatives has been developed. The approach is widely applicable to 2-fluoro-, 2-chloro-, 2-bromo- and 2-nitro-substituted aryl aldehyde and ketone substrates. The fluorescence properties of target compounds were studied.