title: Mirabalin, [corrected] an antitumor macrolide lactam from the marine sponge Siliquariaspongia mirabilis.
abstract: A new highly unsaturated macrolide lactam, termed mirabilin ( 1), was isolated from the aqueous extract of the marine sponge Siliquariaspongia mirabilis. Mirabilin is characterized by the presence of a 35-membered macrolide lactam ring bearing a pentadiene conjugated system and a tetrasubstituted tetrahydropyran ring. A linear polyketide moiety is attached to the macrocyclic ring through an amide linkage. The structure of mirabilin was determined using extensive 2D NMR and ESIMS and tandem MS techniques. Mirabilin inhibits the growth of the tumor cell line HCT-116 with an IC 50 value of 0.27 +/- 0.09 microM and is noncytotoxic to several other cell lines.
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0820, USA.
authors.forename: Alberto
authors.initials: A
authors.lastname: Plaza
authors.forename: Heather L
authors.initials: HL
authors.lastname: Baker
authors.forename: Carole A
authors.initials: CA
authors.lastname: Bewley
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020128:Inhibitory Concentration 50; D018942:Macrolides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D008386:Marine Biology; D008849:Micronesia; D015394:Molecular Structure; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D011161:Porifera / Q000737:chemistry*; D012503:Saponins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D018942:Macrolides; D012503:Saponins; C105644:mirabilin; D009828:Oleanolic Acid