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This document summarizes a study on the use of chiral iron porphyrin complexes as catalysts for remote enantioselective epoxidation reactions. The study found that catalysts with an elongated linker were most effective for olefins that were four carbon atoms away from the lactam binding site. The presence of a hydrogen-bonding interaction between the catalyst and the substrate was also important for achieving high enantioselectivity. However, a high enantioselectivity could only be achieved if the substrate binding offered a kinetic advantage compared to a racemic catalyst. The study provides valuable insights into the factors that influence the enantioselectivity of epoxidation reactions. [Extracted from the article]

Biofilms represent a key challenge in the treatment of microbial infections; for instance, Staphylococcus aureus causes chronic or fatal infections by forming biofilms on medical devices. Herein, the fungus Arcopilus navicularis was found to produce a novel family of PKS-NRPS metabolites that are able to disrupt preformed biofilms of S. aureus . Arcopilins A-F ( 1 - 6 ), tetramic acids, and arcopilin G ( 7 ), a 2-pyridone, were elucidated using HR-ESI-MS and one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy. Their absolute configuration was established by the synthesis of MPTA-esters for 2 , analysis of 1 H- 1 H coupling constants, and ROESY correlations, along with comparison with the crystal structure of 7 . Arcopilin A ( 1 ) not only effectively disrupts preformed biofilms of S. aureus but also potentiates the activity of gentamicin and vancomycin up to 115- and 31-fold times, respectively. Our findings demonstrate the potential application of arcopilins for the conjugated treatment of infections caused by S. aureus with antibiotics unable to disrupt preformed biofilms.