title: Structure of a dihydrooxazole oxa-bridged octalin.
abstract: C26H41NO7, Mr = 479.61, triclinic, P1, a = 11.894 (4), b = 12.360 (2), c = 9.969 (2) A, alpha = 106.11 (2), beta = 100.68 (2), gamma = 99.02 (2) degrees, V = 1349.5 (6) A3, Z = 2, Dx = 1.180 Mg m-3, Mo K alpha, lambda = 0.71069 A, mu = 0.079 mm-1, F(000) = 520, T = 296 K, R = 0.041, wR = 0.047 for 3196 observed unique reflections. A new approach to the total synthesis of the nargenicin macrolide system employing a [2,3] Wittig rearrangement to control the remote C16-C17 stereochemistry required characterization of a pivotal intermediate by X-ray single-crystal methods. The structure is characterized by the formation of strong intermolecular alcohol to dihydrooxazole-N hydrogen bonds, an essentially strain-free tricyclic oxa-bridged octalin nucleus, and low-energy conformations of the methoxymethyl ether side chains.
authors.affiliation: Department of Chemistry, Syracuse University, New York 13244.
authors.forename: R L
authors.initials: RL
authors.lastname: Ostrander
authors.forename: J
authors.initials: J
authors.lastname: Kallmerten
authors.forename: L T
authors.initials: LT
authors.lastname: Rossano
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry; D018942:Macrolides; D008958:Models, Molecular; D015394:Molecular Structure; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D007783:Lactones; D018942:Macrolides; C034625:18-deoxynargenicin A1