New Benzoxazine Secondary Metabolites from an Arctic Actinomycete

• Published in: Marine Drugs
• Main Authors: Kyuho Moon, Chan-Hong Ahn, Yoonho Shin, Tae Hyung Won, Keebeom Ko, Sang Kook Lee, Ki-Bong Oh, Jongheon Shin, Seung-Il Nam, Dong-Chan Oh
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2014
• Subjects: Arctic; marine actinomycete; secondary metabolite; benzoxazine; C-1027; fijiolides; disaccharide; isocitrate lyase; Biology (General); QH301-705.5
• Online Access: https://doi.org/10.3390/md12052526; https://doaj.org/article/2a024a85345c4516916982d184093443

Two new secondary metabolites, arcticoside (1) and C-1027 chromophore-V (2), were isolated along with C-1027 chromophore-III and fijiolides A and B (3–5) from a culture of an Arctic marine actinomycete Streptomyces strain. The chemical structures of 1 and 2 were elucidated through NMR, mass, UV, and IR spectroscopy. The hexose moieties in 1 were determined to be d-glucose from a combination of acid hydrolysis, derivatization, and gas chromatographic analyses. Arcticoside (1) and C-1027 chromophore-V (2), which have a benzoxazine ring, inhibited Candida albicans isocitrate lyase. Chromophore-V (2) exhibited significant cytotoxicity against breast carcinoma MDA-MB231 cells and colorectal carcinoma cells (line HCT-116), with IC50 values of 0.9 and 2.7 μM, respectively.