Genome-Based Mining of Carpatamides I–M and Their Candidate Biosynthetic Gene Cluster

Chemically investigating the marine-derived <i>Streptomyces parvus</i> 1268 led to the isolation of a new compound of carpatamide I (<b>1</b>). Subsequent genomic analysis identified its candidate biosynthetic gene cluster <i>ctd</i> of approximately 44 kb. In order to obtain more carpatamide derivatives, we conducted the upregulation of Ctd14, which is a positive regulator, and obtained improvement of carpatamide I and four new compounds of carpatamides J-M (<b>2</b>-<b>5</b>). The structures of the aforementioned five new isolates were identified by a combination of ESI-HRMS as well as one-dimensional (1D) and two-dimensional (2D) spectral NMR datasets. Bioassay results showed that compounds <b>1</b>-<b>5</b> displayed anti-inflammatory activity and weak cytotoxicity against cell lines of A549, HT-29, and HepG2.