title: Two (E,E)- and (Z,E)-thiazol-5-ylpenta-2,4-dienones.
abstract: In order to characterize the structural elements that might play a role in non-covalent DNA binding by the antitumor antibiotic leinamycin, we have solved the crystal structures of the two leinamycin analogs, methyl (R)-5-[2-[1-(tert-butoxycarbonylamino)ethyl]thiazol-4-yl]penta-(E,E)-2,4-dienoate, C(16)H(22)N(2)O(4)S, (II), and 2-methyl-8-oxa-16-thia-3,17-diazabicyclo[12.2.1]heptadeca-(Z,E)-1(17),10,12,14-tetraene-4,9-dione, C(14)H(16)N(2)O(3)S, (III). The penta-2,4-dienone moiety in both of these analogs adopts a conformation close to planarity, with the thiazole ring twisted out of the plane by 12.9 (2) degrees in (II) and by 21.4 (4) degrees in (III).
authors.affiliation: Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
authors.forename: Leonid
authors.initials: L
authors.lastname: Breydo
authors.forename: Charles L
authors.initials: CL
authors.lastname: Barnes
authors.forename: Kent S
authors.initials: KS
authors.lastname: Gates
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D000478:Alkylation; D000903:Antibiotics, Antineoplastic / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry*; D006860:Hydrogen Bonding; D007769:Lactams; D018942:Macrolides; D008958:Models, Molecular; D013844:Thiazoles / Q000737:chemistry*; D013871:Thiones
chemical_list: D000475:Alkenes; D000903:Antibiotics, Antineoplastic; D007769:Lactams; D018942:Macrolides; D013844:Thiazoles; D013871:Thiones; C467379:thiazol-5-ylpenta-2,4-dienone; C059000:leinamycin; D004247:DNA