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Published on: January 14, 2017
Modification of Biphenolic Anti-Bacterial to Achieve Broad-Spectrum Activity
Cristian Ochoa1, Hanna F Roenfanz1, Marisa C Kozlowski1
1Department of Chemistry Roy and Diana Vagelos Laboratories, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104, USA.
Abstract:
The Gram-positive bacteria, methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative bacteria, Acinetobacter baumannii, are pathogens responsible for millions of nosocomial infections worldwide. Due to the threat of bacteria evolving resistance to antibiotics, scientists are constantly looking for new classes of compounds to treat infectious diseases. The biphenolic analogs of honokiol that were most potent against oral bacteria had similar bioactivity against MRSA. However, all the compounds proved ineffective against A. baumannii. The inability to inhibit A. baumannii is due to the difficult-to-penetrate lipopolysaccharide-coated outer membrane that makes it challenging for antibiotics to enter Gram-negative bacteria. The C 2 scaffold was optimized from the inhibition of Gram-positive bacteria to broad-spectrum antibacterial compounds that inhibit the dangerous Gram-negative pathogen A. baumannii.
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