title: Actinoquinolines A and B, anti-inflammatory quinoline alkaloids from a marine-derived Streptomyces sp., strain CNP975.
abstract: Actinomycete bacteria of the common genus Streptomyces can be routinely isolated from shallow and deep ocean sediments. Although commonly considered a terrestrial genus, and most abundantly found in soil, Streptomyces strains are found that have distinct requirements for seawater and routinely do not show significant similarity, with terrestrial strains by 16S ribosomal DNA phylogenetic sequence comparisons. Our examination of the culture broth of a Streptomyces sp., strain CNP975, isolated from a local La Jolla, California sediment sample, resulted in the isolation of actinoquinolines A and B (1, 2), which show significant inhibition of the arachidonic acid pathway enzymes cyclooxygenases-1 and -2. The new compounds contain the 3-hydroxyquinaldic acid (3HQA) motif found in numerous peptide antibiotics. In the actinoquinolines, 3HQA forms an amide linkage with a linear six-carbon fragment, formally a 2, 6-diamino-1, 5-dihydroxyhexane unit, a component of likely amino acid reductive off-loading origin. Actinoquinoline A illustrated amide rotational isomerism leading to complex NMR spectral data. Actinoquinoline B was assigned as the C-13 aldehyde analog isolated as an intramolecular hemiacetal. Reduction of 2 with NaBH4 yielded actinoquinoline A thus confirming the relative configurations of all centers in the actinoquinolines.
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA, USA.|Department of Pharmacognosy, College of Pharmacy, Beni-Suef University, Beni-Suef, Egypt.
authors.forename: Hossam M
authors.initials: HM
authors.lastname: Hassan
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA, USA.
authors.forename: Chollaratt
authors.initials: C
authors.lastname: Boonlarppradab
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA, USA.
authors.forename: William
authors.initials: W
authors.lastname: Fenical
mesh_terms: D016861:Cyclooxygenase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D006912:Hydroxyquinolines / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D013302:Streptomyces / Q000737:chemistry*
chemical_list: D016861:Cyclooxygenase Inhibitors; D006912:Hydroxyquinolines; C000620224:actinoquinoline A; C000620225:actinoquinoline B