Architecting a Bismacrocycle through a Single C-C Bond Connection
Yunlong Li1, Haokun Li1, Qiyuan Zhou1,2
1Department of Chemistry, City University of Hong Kong, Kowloon 999077, Hong Kong, P. R. China.
JACS Au
|July 30, 2026
Summary
This study presents a novel one-step synthesis for carbazole-based bismacrocycles using Scholl reaction conditions. The resulting bismacrocycle exhibits excellent photocatalytic activity and potential as an anticancer agent.
Area of Science:
- Supramolecular chemistry
- Organic synthesis
- Photocatalysis
Background:
- Covalent linkage of supramolecular entities is key for functional systems.
- Precise, site-selective coupling remains a synthetic challenge.
Purpose of the Study:
- To develop a direct C-C coupling method for carbazole-based macrocycles.
- To investigate the properties and applications of the synthesized compounds.
Main Methods:
- One-step Scholl reaction for C-C coupling.
- Density Functional Theory (DFT) computations.
- Photophysical property analysis and binding constant determination.
- Anticancer activity screening.
Main Results:
- A novel bismacrocycle (1) was synthesized from carbazole precursors (2).
- Distinct formation pathways for monomacrocycle (3) and bismacrocycle (1) were elucidated via DFT.
- Compounds 1-4 showed suitability as C70 hosts.
- Bismacrocycle 1 demonstrated superior photocatalytic activity in debrominative borylation.
- Newly synthesized macrocycles were evaluated for anticancer activities.
Conclusions:
- A versatile synthetic strategy for complex bismacrocycles was established.
- Bismacrocycle 1 shows significant potential as a selective host, photocatalyst, and anticancer agent.
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