title: Neoantimycins A and B, Two Unusual Benzamido Nine-Membered Dilactones from Marine-Derived Streptomyces antibioticus H12-15.
abstract: An actinomycete strain (H12-15) isolated from a sea sediment in a mangrove district was identified asStreptomycesantibioticuson the basis of 16S rDNA gene sequence analysis as well as the investigation of its morphological, physiological, and biochemical characteristics. Two novel benzamido nonacyclic dilactones, namely neoantimycins A (1) and B (2), together with the known antimycins A1ab(3a,b), A2a(4), and A₉ (5), were isolated from the culture broth of this strain. Compounds1and2are the first natural modified ATNs with an unusual benzamide unit. The structures of these new compounds, including their absolute configuration, were established on the basis of HRMS, NMR spectroscopic data, and quantum chemical ECD calculations. Their cytotoxicities against human breast adenocarcinoma cell line MCF-7, the human glioblastoma cell line SF-268, and the human lung cancer cell line NCI-H460 were also tested. All compounds exhibited mild cytotoxic activity. However, Compounds1and2showed no activity againstC. albicansat the test concentration of 1 mg/mL via paper disc diffusion, while the known antimycins showed obvious antifungal activity.
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou 510632, China. kitten_hc@163.com.
authors.forename: Chen
authors.initials: C
authors.lastname: Hu
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou 510632, China. swqtx789@163.com.
authors.forename: Shi-Wen
authors.initials: SW
authors.lastname: Zhou
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou 510632, China. 13751826492@163.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou 510632, China. 13751866247@163.com.
authors.forename: Xin-Heng
authors.initials: XH
authors.lastname: Zheng
authors.affiliation: Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Guangzhou 510632, China. shenhf@gdppri.com.
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Shen
authors.affiliation: Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Guangzhou 510632, China. linbr@126.com.
authors.forename: Bi-Run
authors.initials: BR
authors.lastname: Lin
authors.affiliation: College of Pharmacy, Jinan University, Guangzhou 510632, China. guangxzh@sina.com.
authors.forename: Guang-Xiong
authors.initials: GX
authors.lastname: Zhou
mesh_terms: D001549:Benzamides / Q000737:chemistry* / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D019015:Geologic Sediments / Q000382:microbiology; D006801:Humans; D061986:MCF-7 Cells; D015394:Molecular Structure; D009930:Organic Chemicals / Q000737:chemistry* / Q000494:pharmacology; D011789:Quantum Theory; D013303:Streptomyces antibioticus / Q000737:chemistry / Q000254:growth & development / Q000302:isolation & purification*
chemical_list: D001549:Benzamides; D009930:Organic Chemicals; C037689:benzamide
keywords: ECD calculations; Streptomyces antibioticus; antifungal activity; cytotoxicity; neoantimycins A and B; secondary metabolite; strain identification