# Three naphthomycin type polyketide compounds isolated from strain Streptomyces sp. HKIB0008

## TL;DR

Three new naphthomycin compounds were isolated from a Streptomyces strain and their structures and antimicrobial properties were studied.

## Contribution

The discovery of three new naphthomycin derivatives with unique structural features and antimicrobial activity.

## Key findings

- Three new naphthomycin derivatives (R, S, T) were isolated and structurally characterized.
- Compound R has a novel structural feature due to carbon–carbon bond cleavage and Baeyer–Villiger oxidation.
- Minimum inhibitory concentration assays were performed to assess antimicrobial activity.

## Abstract

Three new naphthomycin derivatives were isolated and identified from Streptomyces sp. HKIB0008, and were designated as naphthomycin R (1), naphthomycin S (2), and naphthomycin T (3). Their structures were elucidated using a combination of spectroscopic techniques, including high-resolution mass spectrometry, and NMR. The naphthoquinone core of 1 underwent carbon–carbon bond cleavage, resulting in a novel structural feature, and a corresponding Baeyer–Villiger oxidation mechanism was proposed. Compounds 2 and 3 possess a complex side chain when compared to known cystine modification on the naphthalenoid core as in the case of naphthomycins I and J. In addition, the minimum inhibitory concentration (MIC) assays for these compounds were conducted.

The online version contains supplementary material available at 10.1007/s13659-026-00591-6.