The crystal structure and the absolute configuration of schelhammerine hydrobromide

Racemates of (η3-allyl)tricarbonyliron lactone complex Fe(CO)3{η1:η3-C(O)XCH2CHCMeCH2} 1a (X = O) and (η3-allyl)tricarbonyliron lactam complex 2a (X = NMe) are resolved on a preparative scale by HPLC on cellulose tris(3,5-dimethylphenyl)carbamate/silica gel RP-8 and the absolute configuration of (-)-2a is determined by X-ray crystal structure analysis.

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Absolute configuration determination of theanti-head-to-head photocyclodimer of anthracene-2-carboxylic acid through cocrystallization withL-prolinol

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270113028461 ◽

2013 ◽

Vol 69 (11) ◽

pp. 1411-1413 ◽

Cited By ~ 3

Author(s):

Yuko Kawanami ◽

Hidekazu Tanaka ◽

Jun-ichi Mizoguchi ◽

Nobuko Kanehisa ◽

Gaku Fukuhara ◽

...

Keyword(s):

Crystal Structure ◽

Circular Dichroism ◽

Carboxylic Acid ◽

Absolute Configuration ◽

Void Space ◽

Circular Dichroism Spectra ◽

The Absolute ◽

Circular Dichroïsm ◽

Hydrogen Bonded

The absolute configuration has been established of the enantiopureanti-head-to-head cyclodimer of anthracene-2-carboxylic acid (AC) cocrystallized with L-propinol and dichloromethane [systematic name: (S)-2-(hydroxymethyl)pyrrolidin-1-ium (5R,6S,11R,12S)-8-carboxy-5,6,11,12-tetrahydro-5,12:6,11-bis([1,2]benzeno)dibenzo[a,e][8]annulene-2-carboxylate dichloromethane monosolvate], C5H12NO+·C30H19O4−·CH2Cl2. In the crystal structure, the AC dimer interacts with L-prolinol through a nine-membered hydrogen-bonded ring [R22(9)], while the dichloromethane molecule is incorporated to fill the void space. The absolute configuration determined in this study verifies a recent assignment made by comparing theoreticalversusexperimental circular dichroism spectra.

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(3R,4R)-(–)-3-Hydroxymethyl-4-phenyl-2-o-toluoyl-1,2,3,4-tetrahydroisoquinoline

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536806012189 ◽

2006 ◽

Vol 62 (5) ◽

pp. o1774-o1776 ◽

Cited By ~ 1

Author(s):

Andrzej Gzella ◽

Maria Chrzanowska ◽

Agnieszka Dreas ◽

Michał S. Kaczmarek ◽

Zenon Woźniak

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Absolute Configuration ◽

Title Compound ◽

Phenyl Ring ◽

Heterocyclic Ring ◽

Hydroxymethyl Group ◽

Envelope Conformation ◽

Compound C ◽

The Absolute

The absolute configuration of the title compound, C24H23NO2, has been confirmed as 3R,4R. The hydroxymethyl group and phenyl ring at the asymmetric C atoms exhibit α and β orientations, respectively, and the non-planar heterocyclic ring of the tetrahydroisoquinoline system adopts an envelope conformation. The crystal structure is stabilized through hydrogen bonds.

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(3aS,5aR,6R,8aR)-3a-Hydroxy-5a-methyl-6-[(1R,2E,4R)-1,4,5-trimethyl-2-hexen-1-yl]-3a,4,5,5a,6,7,8,8a-octahydro-2H-cyclopenta[e]benzofuran-2-one

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536807047307 ◽

2007 ◽

Vol 63 (11) ◽

pp. o4196-o4196

Author(s):

Wen-liang Wang ◽

Hong-wen Tao ◽

Wei Sun ◽

Qian-Qun Gu ◽

Wei-Ming Zhu

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Absolute Configuration ◽

Title Compound ◽

Optical Rotation ◽

Side Chain ◽

Compound C ◽

Extended Chain ◽

Halotolerant Fungus ◽

The Absolute

The title compound, C21H32O3, also known as dimethylincisterol A3, was isolated from halotolerant fungus THW-18. It is composed of three fused rings and a side chain. In the crystal structure, the molecules interact with each other via O—H...O hydrogen bonds, resulting in an extended chain along the b axis. The absolute configuration was assigned from the measured optical rotation and reference to the literature.

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ChemInform Abstract: THE CRYSTAL STRUCTURE AND THE ABSOLUTE CONFIGURATION OF (+)-2,3-6,7-DIBENZOBICYCLO(3.3.1)NONA-2,6-DIENE-4,8-DIYL BIS(P-BROMOBENZOATE)

Chemischer Informationsdienst ◽

10.1002/chin.197638077 ◽

1976 ◽

Vol 7 (38) ◽

pp. no-no

Author(s):

TSUGUHIRO KANEDA ◽

CHUJI KATAYAMA ◽

JIRO TANAKA

Keyword(s):

Crystal Structure ◽

Absolute Configuration ◽

The Absolute

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(1R,4S,8R,12S,13S,14R,16S,19R)-14-Hydroxy-7,7-dimethyl-17-methylene-2,9,18-trioxo-3,10-dioxapentacyclo[14.2.1.01,13.04,12.08,12]nonadec-19-yl acetate

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s1600536807052099 ◽

2007 ◽

Vol 63 (11) ◽

pp. o4439-o4439

Author(s):

Hao Shi

Keyword(s):

Crystal Structure ◽

Hydrogen Bonds ◽

Absolute Configuration ◽

Title Compound ◽

Chair Conformation ◽

Boat Conformation ◽

Asymmetric Unit ◽

Compound C ◽

Independent Molecules ◽

The Absolute

The title compound, C22H26O8, prepared from the natural diterpenoid Macrocalyxin J, is built up from five fused rings. Cyclohenane ring A adopts a chair conformation, ring B exists in a screw-boat conformation and ring C adopts a boat conformation; the two five membered rings adopt envelope conformations. Two unique molecules are present in the asymmetric unit; both independent molecules have the same absolute configuration, the absolute configuration being deduced from the chirality of Macrocalyxin A, which was isolated from the same plant (i.e. Rabdosia macrocalyx) as Macrocalyxin J. The crystal structure displays intermolecular O—H...O hydrogen bonds.

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