A pair of epimeric 13-hydroxy-2,3,6,7-tetramethoxy-8b,11,12,12a,13,13a-hexahydro-9H-9a-azacyclopenta[b]triphenylene-10-ones.
The structures of two compounds which are intermediates in the synthesis of phenanthroindolizidine alkaloids have been determined. (8bS,13aS,14R,14aR)-8b,9,11,12,13,13a,14,14a-Octahydro-14-hydroxy-2,3,6,7-tetramethoxydibenzo[f,h]pyrrolo[1,2-b]isoquinolin-11-one acetone solvate, C24H27NO6.C3H6O, (II), crystallizes in a chiral space group with one solvent molecule (acetone) present in the asymmetric unit. On the other hand, (8bS,13aS,14S,14aR)-8b,9,11,12,13,13a,14,14a-octahydro-14-hydroxy-2,3,6,7-tetramethoxydibenzo[f,h]pyrrolo[1,2-b]isoquinolin-11-one, C24H27NO6, (III), crystallizes in a centrosymmetric space group with two molecules in the asymmetric unit and with no solvent present. The two molecules in the asymmetric unit of (III) are structurally the same. Compounds (II) and (III) are epimers at the C atom carrying the OH group; otherwise they are very similar in structure.
Nygren
Cara
C
Department of Chemistry, University of Tennessee, Knoxville, TN 37996, USA.
Chen
Tianniu
T
Zhong
Sanbao
S
Kaczmarek
Conrad
C
Turner
John F C
JF
Baker
David C
DC
D000470:Alkaloids / Q000138:chemical synthesis; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D007212:Indolizines / Q000138:chemical synthesis; D007546:Isoquinolines / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D010616:Phenanthrenes / Q000138:chemical synthesis; D011758:Pyrroles / Q000737:chemistry; D013237:Stereoisomerism
D000470:Alkaloids; D007212:Indolizines; D007546:Isoquinolines; D007659:Ketones; D010616:Phenanthrenes; D011758:Pyrroles; C004218:tylophorine