title: Structure assignment of lucentamycin E and revision of the olefin geometries of the marine-derived lucentamycins.
abstract: A new lucentamycin analogue, lucentamycin E (5), was isolated from the culture broth of the marine-derived actinomycete Nocardiopsis lucentensis, strain CNR-712. The absolute stereostructure of 5 was assigned by comprehensive analyses of NMR data and by application of the advanced Marfey's method. The planar structure of 5 was analogous to lucentamycins A-D, whereas the olefin geometry of the 3-methyl-4-ethylideneproline moiety was found to be E, opposite of that previously reported. Consequently, a reinvestigation of the olefin geometries of the 3-methyl-4-ethylideneproline residues of lucentamycins A-D showed that the olefin geometries of the substituted proline functionalities must be revised to (2S,3R,E)-3-methyl-4-ethylideneproline.
authors.affiliation: Natural Medicine Center, Korea Institute of Science and Technology, Gangneung, Gangwon-do 210-340, Republic of Korea.
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Cha
authors.forename: Jin-Soo
authors.initials: JS
authors.lastname: Park
authors.forename: Taebo
authors.initials: T
authors.lastname: Sim
authors.forename: Sang-Jip
authors.initials: SJ
authors.lastname: Nam
authors.forename: Hak Cheol
authors.initials: HC
authors.lastname: Kwon
authors.forename: Juan R
authors.initials: JR
authors.lastname: Del Valle
authors.forename: William
authors.initials: W
authors.lastname: Fenical
mesh_terms: D039903:Actinobacteria / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry*; D001444:Bahamas; D008386:Marine Biology; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000737:chemistry*; D011392:Proline / Q000031:analogs & derivatives / Q000737:chemistry
chemical_list: D000475:Alkenes; D009842:Oligopeptides; C523222:lucentamycin A; C577386:lucentamycin E; D011392:Proline