Biosynthetic engineering of the antifungal, anti-MRSA auroramycin.

Using an established CRISPR-Cas mediated genome editing technique for streptomycetes, we explored the combinatorial biosynthesis potential of the auroramycin biosynthetic gene cluster in Streptomyces roseosporous. Auroramycin is a potent anti-MRSA polyene macrolactam. In addition, auroramycin has antifungal activities, which is unique among structurally similar polyene macrolactams, such as incednine and silvalactam.

Bromomethylthioindole Inspired Carbazole Hybrids as Promising Class of Anti-MRSA Agents.

Series of -substituted carbazole analogues bearing an indole ring were synthesized as anti-methicillin-resistant (MRSA) agents from a molecular hybridization approach. The representative compound showed an MIC = 1 μg/mL against a panel of MRSA clinical isolates as it possessed comparable activities to that of vancomycin. Moreover, compound also exhibited MIC = 1 μg/mL activities against a recent identified Z172 MRSA strain (vancomycin-intermediate and daptomycin-nonsusceptible phenotype) and the vancomycin-resistant (VRE) strain.

Tandem three-component reactions of aldehyde, alkyl acrylate, and dialkylmalonate catalyzed by ethyl diphenylphosphine.

A new highly efficient three-component reaction of alkyl acrylate, aldehyde and dialkyl malonate using ethyl diphenylphosphine as organocatalyst has been described. Various highly functional compounds bearing hydroxyl groups and the ester functions can be easily prepared in moderate to good yields according to our one-step procedure. The reactions are believed to proceed via Morita-Baylis-Hillman reactions of alkyl acrylate and aldehydes, followed by the Michael addition reactions of dialkyl malonates.

Preparation of tetrasubstituted furans via intramolecular Wittig reactions with phosphorus ylides as intermediates.

Novel preparation of tetrasubstituted furans, starting from the Michael acceptors, tributylphosphine, and acyl chlorides, is realized. A broad range of highly functional furans can be efficiently generated in one step at room temperature within 10 min to 21 h in moderate to high yields (60-99%). The reaction was proposed to proceed via intramolecular Wittig-type reactions, using phosphorus ylides as intermediates.