title: 11-Methyl-12a-phenyl-9a,12a-dihydrophenanthro[9',10':5,6][1,4]dioxino[2,3-d]oxazole and 9a-(10-hydroxyphenanthren-9-yl)-11,12a-diphenyl-9a,12a-dihydrophenanthro[9',10':5,6][1,4]dioxino[2,3-d]oxazole.
abstract: In the title compounds, C(24)H(17)NO(3), (I), and C(43)H(27)NO(5), (II), the dioxine ring is not planar and tends toward a boat conformation. The oxazoline ring adopts a twisted conformation in molecule (I) but is essentially planar in molecule (II). The configuration of the dioxine-oxazoline system is determined by the sp(3) state of the two shared atoms. The phenanthrene moiety is nearly coplanar with the dioxine ring, while the phenyl ring is perpendicular to the attached oxazole ring. The triclinic unit cell of (II) contains two crystallographically independent molecules related by a pseudo-inversion centre.
authors.affiliation: X-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia.
authors.forename: Anwar
authors.initials: A
authors.lastname: Usman
authors.forename: Ibrahim Abdul
authors.initials: IA
authors.lastname: Razak
authors.forename: Hoong-Kun
authors.initials: HK
authors.lastname: Fun
authors.forename: Suchada
authors.initials: S
authors.lastname: Chantrapromma
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Xu