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Abstract Cationic bottlebrush homopolymers are polymerized using a grafting‐through approach by ring‐opening metathesis polymerization (ROMP) to afford well‐defined polymers. Quaternary ammonium macromonomers (MMs) are prepared by quaternizing tertiary amine MMs synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization. The quaternary ammonium MMs undergo ROMP to target molecular weights (Mn= 30 000–100 000 g mol−1) and a low dispersity (Đ= 1.10–1.30). Halide‐ligand exchange between the third generation Grubbs catalyst (G3) and halide counter ions (bromide and iodide ions) of MMs changes the catalyst activity throughout ROMP, causing it to deviate from pseudo‐first order kinetic behavior; however, the polymerization still follows controlled behavior without significant catalyst termination. Increasing steric bulk of the MMs decreases the polymerization rate as well. Amphiphilic block copolymers are synthesized by sequential polymerization of quaternary ammonium MMs and polystyrene (PS) MMs. Using a PS macroinitiator affords block copolymers with lowerĐvalues as compared to the less active cationic macroinitiator.
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Chimeric Amphiphilic Disinfectants: Quaternary Ammonium/Quaternary Phosphonium Hybrid Structures
Abstract Cationic biocides play a crucial role in the disinfection of domestic and healthcare surfaces. Due to the rise of bacterial resistance towards common cationic disinfectants like quaternary ammonium compounds (QACs), the development of novel actives is necessary for effective infection prevention and control. Toward this end, a series of 15 chimeric biscationic amphiphilic compounds, bearing both ammonium and phosphonium residues, were prepared to probe the structure and efficacy of mixed cationic ammonium‐phosphonium structures. Compounds were obtained in two steps and good yields, with straightforward and chromatography‐free purifications. Antibacterial activity evaluation of these compounds against a panel of seven bacterial strains, including two MRSA strains as well as opportunistic pathogenA. baumannii, were encouraging, as low micromolar inhibitory activity was observed for multiple structures. Alkyl chain length on the ammonium group was, as expected, a major determinant of bioactivity. In addition, high therapeutic indexes (up to 125‐fold) for triphenyl phosphonium‐bearing amphiphiles were observed when comparing antimicrobial activity to mammalian cell lysis activity.
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- Award ID(s):
- 2215854
- PAR ID:
- 10495413
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemMedChem
- Volume:
- 19
- Issue:
- 11
- ISSN:
- 1860-7179
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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