title: Dandamycin and chandrananimycin E, benzoxazines from Streptomyces griseus.
abstract: Two new benzoxazines were isolated from Streptomyces griseus (HKI 0545) and assigned as chandrananimycin E (1) and dandamycin (2). Although a number of phenoxazinone-type compounds have been reported from nature, phenoxazines are rarer, and carbon substitution at N-10 such as in 1 is unprecedented. The cyclopentene-containing ring structure of dandamycin (2) is also unique. Chandrananimycin E (1) was found to possess moderate antiproliferative activity against HUVEC cells (GI50 35.3 μM) and weak cytotoxic activity towards HeLa cells (CC50 56.9 μM). Dandamycin showed neither antiproliferative activity nor cytotoxicity towards these cell lines. Structure activity comparisons with phenoxazinones isolated from S. griseus HKI 0545 suggested that the alteration of the core ring systems in 1 and 2 diminishes their activity. Natural products 1 and 2 are interesting additions to the rich secondary metabolome of S. griseus and constitute an important addition to the body of knowledge on phenoxazinone-derived metabolites.
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany.
authors.forename: Emma C
authors.initials: EC
authors.lastname: Barnes
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany.
authors.forename: Patricia
authors.initials: P
authors.lastname: Bezerra-Gomes
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Nett
authors.affiliation: 1] Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany [2] Chair for Natural Product Chemistry, Friedrich Schiller University, Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Hertweck
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000737:chemistry / Q000302:isolation & purification*; D048588:Benzoxazines / Q000737:chemistry / Q000302:isolation & purification*; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects / Q000502:physiology; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology; D006801:Humans; D015394:Molecular Structure; D013305:Streptomyces griseus / Q000737:chemistry* / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D000903:Antibiotics, Antineoplastic; D048588:Benzoxazines