Ionized water-soluble organic nanosheets with light/ultrasound dual excitation channels for efficient killing of multidrug-resistant bacteria.

A novel ionized heavy-atom-free two-dimensional organic nanosheet was prepared and exhibited highly selective generation of singlet oxygen under both light and ultrasound excitation. These ionized nanosheets displayed excellent dispersibility in water and enhanced singlet oxygen production efficiency compared to their non-assembled monomers. Antimicrobial experiments have revealed their potent bactericidal effects on drug-resistant and under both visible light and ultrasound irradiation.

Tricking enzymes in living cells: a mechanism-based strategy for design of DNA topoisomerase biosensors.

Most activity-based molecular probes are designed to target enzymes that catalyze the breaking of chemical bonds and the conversion of a unimolecular substrate into bimolecular products. However, DNA topoisomerases are a class of enzymes that alter DNA topology without producing any molecular segments during catalysis, which hinders the development of practical methods for diagnosing these key biomarkers in living cells. Here, we established a new strategy for the effective sensing of the expression levels and catalytic activities of topoisomerases in cell-free systems and human cells.

Rational Functionalization of a C Buckybowl To Enable a C:Buckybowl Cocrystal for Organic Semiconductor Applications.

Fullerene fragments, referred to as buckybowls, are garnering interest due to their distinctive molecular shapes and optoelectronic properties. Here, we report the synthesis and characterization of a novel C subunit, diindeno[4,3,2,1-:4',3',2',1'-]perylene, that is substituted with either triethylsilyl(TES)-ethynyl or 2,4,6-triisopropylphenyl groups at the -positions. The resulting compounds ( and ) display a bowl-to-bowl inversion at room temperature.

Synthesis of Tripeptide Derivatives with Three Stereogenic Centers and Chiral Recognition Probed by Tetraaza Macrocyclic Chiral Solvating Agents Derived from d-Phenylalanine and (1 S,2 S)-(+)-1,2-Diaminocyclohexane via H NMR Spectroscopy.

Enantiomers of a series of tripeptide derivatives with three stereogenic centers (±)-G1-G9 have been prepared from d- and l-α-amino acids as guests for chiral recognition by H NMR spectroscopy. In the meantime, a family of tetraaza macrocyclic chiral solvating agents (TAMCSAs) 1a-1d has been synthesized from d-phenylalanine and (1 S,2 S)-(+)-1,2-diaminocyclohexane. Discrimination of enantiomers of (±)-G1-G9 was carried out in the presence of TAMCSAs 1a-1d by H NMR spectroscopy.

Spiro-Fused Perylene Diimide Arrays.

The straightforward palladium-catalyzed synthesis protocol toward spiro-fused perylene diimides is developed. The reaction involves two palladium-catalyzed C-H activations and 4-fold C-C bond formation sequence from readily available precursors. This facile and step-economic approach also provides another convenient access to ethylene-bridged dimer (NDP) and further π-extended spiro system (SNTP).

Discrimination of Enantiomers of Dipeptide Derivatives with Two Chiral Centers by Tetraaza Macrocyclic Chiral Solvating Agents Using H NMR Spectroscopy.

H NMR spectroscopy is often used to discriminate enantiomers of chiral analytes and determine their enantiomeric excess (ee) by various chiral auxiliaries. In reported research, these studies were mainly focused on chiral discriminantion of chiral analytes with only one chiral center. However, many chiral compounds possessing two or more chiral centers are often found in natural products, chiral drugs, products of asymmetric synthesis and biological systems.