Azalomycin F4a 2-ethylpentyl ester, a new macrocyclic lactone, from mangrove actinomycete Streptomyces sp. 211726

Azalomycin F4a 2-ethylpentyl ester, a new 36-membered macrocyclic lactone antibiotic, was isolated from mangrove actinomycete Streptomyces sp. 211726. Its structure was elucidated on the basis of spectroscopic data. The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116.