title: New nemadectin congener from Streptomyces microflavus neau3: fermentation, isolation, structure elucidation and biological activities.
abstract: Bioactivity-guided fractionation of Streptomyces microflavus neau3 fermentation broth was used to determine the chemical identity of bioactive constituents. The structure of the new compound 1 was determined on the basis of spectroscopic analysis, including 1D and 2D NMR, as well as HRESI-MS, ESI-MS, UV and IR, and compared with the data reported in the literature. The acaricidal and nematocidal activities of the isolated compound 1 and its previously reported analogs 2, 3, 4 and 5 were evaluated. The results demonstrate that compounds 1, 2, 3, 4 and 5, especially compound 1, have potential as antiparasitics with acaricidal and nematocidal activities. These lactones shed new insights into the structural diversity of nemadectin and milbemycin analog libraries that are potentially accessible by combinatorial biosynthesis.
authors.affiliation: School of Life Science, Northeast Agricultural University, Harbin, PR China.
authors.forename: Wen-Sheng
authors.initials: WS
authors.lastname: Xiang
authors.forename: Ji-Dong
authors.initials: JD
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.forename: Xiang-Jing
authors.initials: XJ
authors.lastname: Wang
mesh_terms: D000818:Animals; D000969:Antinematodal Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D017173:Caenorhabditis elegans; D005285:Fermentation; D007306:Insecticides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D018942:Macrolides / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D019906:Nuclear Magnetic Resonance, Biomolecular; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013302:Streptomyces / Q000737:chemistry* / Q000378:metabolism; D040102:Tetranychidae
chemical_list: D000969:Antinematodal Agents; D007306:Insecticides; D018942:Macrolides