Proximicin A, B and C, novel aminofuran antibiotic and anticancer compounds isolated from marine strains of the actinomycete Verrucosispora.

A family of three novel aminofuran antibiotics named as proximicins was isolated from the marine Verrucosispora strain MG-37. Proximicin A was detected in parallel in the marine abyssomicin producer "Verrucosispora maris" AB-18-032. The characteristic structural element of proximicins is 4-amino-furan-2-carboxylic acid, a hitherto unknown gamma-amino acid. Proximicins show a weak antibacterial activity but a strong cytostatic effect to various human tumor cell lines.