Anithiactins A–C, Modified 2-Phenylthiazoles from a Mudflat-Derived Streptomyces sp.

Intensive investigation of the chemical components of a Streptomyces sp. isolated from mudflat sediments collected on the southern coast of the Korean peninsula led to the isolation of three new compounds, anithiactins A-C (1-3). The chemical structures of anithiactins A and C were determined by interpretation of NMR data analyses, while the chemical structure of anithiactin B was established from a combination of NMR spectroscopic and crystallographic data analyses. The structure of anithiactin A was also confirmed by total synthesis. These three anithiactins displayed moderate acetylcholinesterase inhibitory activity with no significant cytotoxicity.