Enantioselective Effect of Chiral Small Molecules in SARS-CoV-2 Vaccine-Induced Immune Response.

Although numerous chiral small molecules have been discovered and synthesized, the investigation on their enantioselective immunological effects remains limited. In this study, we designed and synthesized a pair of small molecule enantiomers (R/S-ResP) by covalently bonding two immunostimulators (resiquimod/Res) onto a planar chiral framework (paracyclophane/P). Notably, we found that S-ResP exhibits a 4.05-fold higher affinity for toll-like receptor 7 (TLR7) than R-ResP, thereby more effectively enhancing the functions of dendritic cells and macrophages in cytokine secretion and antigen internalization. Furthermore, we observed that S-ResP significantly enhances RBD antigen-induced cross-neutralization against various SARS-CoV-2 strains compared to R-ResP. These findings demonstrate the enantioselective effects of small molecules on regulating vaccine-induced immune responses and emphasize the significance of chirality in designing small molecular adjuvants.

One-Pot Construction of Heteroarylation/Esterification Products of Acrylic Acids via Iridium(III)-Catalyzed C-H Activation.

A carboxylate-assisted iridium(III)-catalyzed regioselective C(sp2)-H heteroarylation/esterification reaction of acrylic acid is disclosed herein for the first time. This catalytic protocol tolerates various α-substituted, ß-substituted, and α, ß-disubstituted acrylic acids as well as heteroaromatic boronates well. The resulting 3,4-dihydro-2H-pyran-6-carboxylic acid derivative 3r highlighted the AIE-active luminophore with multiple emission signal properties and a high quantum yield of 28%, exhibiting the potential application of this methodology for the synthesis of nitrogen-containing organic functional materials.

AIE-active aurones for circularly polarized luminescence and trace water detection.

AIE-active phenyl- and [2.2]paracyclophanyl-based aurones (2-Ph and 2-PCP) were synthesized and investigated with different structures and photophysical properties. The results illustrated that the PCP ring can provide chirality, electron-donating ability and steric hindrance. Accordingly, (Rp)/(Sp)-2-PCP exhibit high sensitivity in trace water detection and aggregation-induced CPL with enhanced quantum yields and luminescence dissymmetry factors.

3D Boranil Complexes with Aggregation-Amplified Circularly Polarized Luminescence.

The development of small organic CPL-active molecules with large luminescent dissymmetry factors is highly demanded due to their promising applications in chiroptical devices and sensors. This work describes the design and synthesis of a new family of CPL-active BF2 complexes, (Rp)/(Sp)-3a-3e, which were constructed by fusing a N̂O-chelated BF2 complex with [2.2]paracyclophane. These complexes display aggregation-amplified CPL with moderate dissymmetry factors values and moderate quantum yields both in solution and in the solid state. In addition, these photophysical properties were rationalized via X-ray diffraction and TD-DFT calculations.

Planar chiral [2.2]paracyclophanyl-based boron fluoride complexes: synthesis, crystal structure and photophysical properties.

Planar chiral [2.2]paracyclophanyl-based boron fluoride complexes (3a-3d) were designed and facilely synthesized. The X-ray structure study, theoretical calculations and CD spectra reveal the intense emission and planar chiral structures of these complexes. In particular, 3a-3d show moderate quantum yields and large Stokes shifts both in solution and solid state. Furthermore, the blue-shifted mechanochromic properties of 3a and 3b were both investigated in the solid state. This work is the first study on planar chiral boron monofluoride complexes within the boron fluoride complex field.