Rubichaetoglobin A, a new cytochalasan alkaloid isolated from the plant endophytic fungus Chaetomium tectifimeti S104

Abstract

Rubichaetoglobin A (1), a new cytochalasan alkaloid, together with nine closely related known ones (2-10), were isolated from the ethyl acetate extracts of the endophytic fungus Chaetomium tectifimeti S104 harbored in the root of Rubia podantha Diels. Their structures were elucidated based on comprehensive spectroscopic analysis. All isolated compounds were tested for cytotoxic, antibacterial, and nitric oxide inhibitory activities. The results showed that 2, 4, and 5 possessed moderate cytotoxicity against MDA-MB-231 cells with the IC₅₀ values of 19.14, 11.43, and 10.27 μM, respectively.

Graphical Abstract

Keywords:

• Chaetomium tectifimeti
• cytochalasan alkaloids
• rubichaetoglobin A
• structure elucidation
• cytotoxicity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (32070387, 32070356, 21702231), the Natural Science Foundation of Jiangsu Province (BK20170745), the National New Drug Innovation Major Project of Ministry of Science and Technology of China (2017ZX09309027), the Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX21_0687), and "Double First-Class" Project of China Pharmaceutical University (CPU2018GF05).