Dysidamide, a Novel Metabolite From a Red Sea Sponge Dysidea herbacea

A hexachloro metabolite, dysidamide (2) has been isolated from a Red Sea sponge Dysidea herbacea. The structure of (2) has been established from spectroscopic and chemical evidence, and confirmed by an X-ray crystal structure determination. Crystals of (2) are orthorhombic P212121, a 20.509(13), b 18.411(11), c 11.356(9)Ǻ, Z 8. The structure was refined by least-squares methods to a residual of 0.049 for 2277 'observed' reflections. Two different conformations of the molecule are present in the crystal.

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Chemistry and Crystal Structures of Some Constituents of Zingiber cassumunar

Australian Journal of Chemistry ◽

10.1071/ch9790071 ◽

1979 ◽

Vol 32 (1) ◽

pp. 71 ◽

Cited By ~ 29

Author(s):

T Amatayakul ◽

J Cannon ◽

P Dampawan ◽

T Dechatiwongse ◽

RF Giles ◽

...

Keyword(s):

Crystal Structure ◽

Least Squares ◽

Crystal Structures ◽

Structure Determination ◽

Aromatic Compounds ◽

Crystal Structure Determination ◽

The Novel ◽

X Ray ◽

Zingiber Cassumunar ◽

Block Diagonal

The novel aromatic compounds cis-3-(2',4',5'-trimethoxyphenyl)-4-[(E)-2''',4''',5'''-trimethoxy-styryl]cyclohex-1-ene(1), cis-3-(3',4'-dimethoxyphenyl)-4-[(E)-3''',4'''-dimethoxystyryl]cyclohex-1-ene (2), a substance assigned the tentative structure cis-3-(3',4'-dimethoxyphenyl)-4-[(E)-2''',4''',5'''- trimethoxystyryl]cyclohex-1-ene (3),(E)-4-(3',4'-dimethoxypheny1)but-3-en-1-ol (5), (E)-4-(3',4'-dimethoxypheny1)but-3-en-1-yl acetate (6), and 8-(3',4'-dimethoxyphenyl)-2-methoxynaphtho-1,4- quinone (7) have been isolated from the rhizomes of Zingiber cassurnunav Roxb. (Zingiberaceae). The crystal structures of the cyclohexene derivative (1) and the quinone (7) have been determined from X-ray diffractometer data at 295 K and refined by block diagonal least squares to residuals of 0.046 (2099 'observed' reflections) and 0.093 (1246), respectively. Crystals of compound (1) are triclinic, P1, a 18.027(12), b 10.037(9), c 6.530(5) α, 84.22 (7), β 81.87 (6), γ 85.72 (6)�, Z 2. Crystals of the quinone (7) are monoclinic, P21/a, a 22.89 (1), b 8.022 (5), c 8.458 (5) �, β 91.98 (5)�, Z 4. Although the latter crystal structure determination is imprecise, due largely to the very small size of the crystal available, the solution is unambiguous. A simple two-step synthesis of the quinone (7) has been achieved.

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Faculty Opinions recommendation of De novo protein crystal structure determination from X-ray free-electron laser data.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718185624.793487506 ◽

2013 ◽

Author(s):

Chantal Abergel

Keyword(s):

Crystal Structure ◽

Structure Determination ◽

Free Electron ◽

Free Electron Laser ◽

De Novo ◽

Crystal Structure Determination ◽

Protein Crystal ◽

X Ray ◽

Protein Crystal Structure ◽

Laser Data

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The Kinetics of Substitution Reactions of Mixed Platinum(II)-Bis(nucleoside) Complexes in Aqueous Solution in the Presence of Thiourea; X-Ray Crystal Structure Determination ofcis-[Pt(NH3)2(adenosine-N7)2](ClO4)2⋅3.5 H2O

Chemistry - A European Journal ◽

10.1002/1521-3765(20000915)6:18<3404::aid-chem3404>3.0.co;2-r ◽

2000 ◽

Vol 6 (18) ◽

pp. 3404-3413 ◽

Cited By ~ 18

Author(s):

Marjaana Mikola ◽

Karel D. Klika ◽

Jorma Arpalahti

Keyword(s):

Crystal Structure ◽

Aqueous Solution ◽

Structure Determination ◽

Crystal Structure Determination ◽

Substitution Reactions ◽

X Ray ◽

Kinetics Of

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ChemInform Abstract: Spectroscopic Studies and X-Ray Crystal Structure Determination of the Complex cis-(S-Ethylcysteine)platinum(II)dichloride.

Chemischer Informationsdienst ◽

10.1002/chin.198238072 ◽

1982 ◽

Vol 13 (38) ◽

Author(s):

V. THEODOROU ◽

I. PHOTAKI ◽

N. HADJILIADIS ◽

R. W. GELLERT ◽

R. BAU

Keyword(s):

Crystal Structure ◽

Structure Determination ◽

Spectroscopic Studies ◽

Crystal Structure Determination ◽

X Ray

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New similarity index for crystal structure determination from X-ray powder diagrams

Journal of Applied Crystallography ◽

10.1107/s0021889805023484 ◽

2005 ◽

Vol 38 (6) ◽

pp. 861-866 ◽

Cited By ~ 16

Author(s):

Detlef Walter Maria Hofmann ◽

Ludmila Kuleshova

Keyword(s):

Crystal Structure ◽

Structure Determination ◽

Structure Prediction ◽

Similarity Index ◽

Crystal Structure Determination ◽

Crystal Structure Prediction ◽

X Ray ◽

Organic Pigments ◽

Structure Solution ◽

Similarity Indices

A new similarity index for automated comparison of powder diagrams is proposed. In contrast to traditionally used similarity indices, the proposed method is valid in cases of large deviations in the cell constants. The refinement according to this index closes the gap between crystal structure prediction and automated crystal structure determination. The opportunities of the new procedure have been demonstrated by crystal structure solution of un-indexed powder diagrams of some organic pigments (PY111, PR181 and Me-PR170).

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