scholarly journals Some experimental aspects of absolute configuration determination using single crystal X-ray diffraction

2017 ◽  
Vol 28 (10) ◽  
pp. 1330-1336 ◽  
Author(s):  
Amber L. Thompson ◽  
Sarah F. Jenkinson ◽  
George W.J. Fleet
Keyword(s):  
Single Crystal ◽  
Absolute Configuration ◽  
X Ray Diffraction ◽  
X Ray

Crystal structures of (S)- and (R,S)-2,2′-bipyridine-3,3′-dicarboxylic acid 1,1′-dioxides and of their barium salts: absolute configuration and molecular distortion enforced by supramolecular self-assembly

1997 ◽  
Vol 212 (3) ◽  
Author(s):  
P. Vojtíšek ◽  
I. Císařová ◽  
J. Podlaha ◽  
Z. Žák ◽  
S. Böhm ◽  
...  
Keyword(s):  
Single Crystal ◽  
Dicarboxylic Acid ◽  
Crystal Structures ◽  
Absolute Configuration ◽  
Self Assembly ◽  
Barium Salt ◽  
X Ray Diffraction ◽  
X Ray

AbstractCrystal structures of the title compounds were determined by single crystal X-ray diffraction. Absolute configuration of the barium salt of (+)-(

Absolute configuration and domain structure of AlPO4-5 studied by single crystal X-ray diffraction

2000 ◽  
Vol 38 (2-3) ◽  
pp. 403-412 ◽  
Author(s):  
G.J Klap ◽  
H van Koningsveld ◽  
H Graafsma ◽  
A.M.M Schreurs
Keyword(s):  
Single Crystal ◽  
Domain Structure ◽  
Absolute Configuration ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals Crystal structure of 5-[(benzoyloxy)methyl]-5,6-dihydroxy-4-oxocyclohex-2-en-1-yl benzoate

2020 ◽  
Vol 76 (7) ◽  
pp. 1096-1100
Author(s):  
Theerachart Leepasert ◽  
Patchreenart Saparpakorn ◽  
Kittipong Chainok ◽  
Tanwawan Duangthongyou
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Single Crystal ◽  
Natural Product ◽  
Dihedral Angle ◽  
Absolute Configuration ◽  
Hydroxyl Groups ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ring Form

The crystal structure of the natural product zeylenone, C21H18O7, was confirmed by single-crystal X-ray diffraction. The crystal structure has three chiral centers at positions C1, C5 and C6 of the cyclohexanone ring, but the absolute configuration could not be determined reliably. The methyl benzoate and benzoyloxy substituents at positions C1 and C5 of the cyclohexenone ring are on the same side of the ring with the dihedral angle between their mean planes being 16.25 (10)°. These rings are almost perpendicular to the cyclohexenone ring. The benzoate groups and two hydroxyl groups on the cyclohexenone ring form strong hydrogen bonds to consolidate the crystal structure. In addition, weak C—H...O hydrogen bonds also contribute to the packing of the structure.

scholarly journals Secondary Metabolites with α-Glucosidase Inhibitory Activity from the Mangrove Fungus Mycosphaerella sp. SYSU-DZG01

Marine Drugs ◽  
2019 ◽  
Vol 17 (8) ◽  
pp. 483 ◽  
Author(s):  
Pei Qiu ◽  
Zhaoming Liu ◽  
Yan Chen ◽  
Runlin Cai ◽  
Guangying Chen ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Secondary Metabolites ◽  
Single Crystal ◽  
Absolute Configuration ◽  
Inhibitory Activity ◽  
Spectroscopic Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ic50 Values ◽  
New Metabolites

Four new metabolites, asperchalasine I (1), dibefurin B (2) and two epicoccine derivatives (3 and 4), together with seven known compounds (5–11) were isolated from a mangrove fungus Mycosphaerella sp. SYSU-DZG01. The structures of compounds 1–4 were established from extensive spectroscopic data and HRESIMS analysis. The absolute configuration of 1 was deduced by comparison of ECD data with that of a known structure. The stereostructures of 2–4 were further confirmed by single-crystal X-ray diffraction. Compounds 1, 8 and 9 exhibited significant α-glucosidase inhibitory activity with IC50 values of 17.1, 26.7 and 15.7 μM, respectively. Compounds 1, 4, 6 and 8 showed antioxidant activity by scavenging DPPH· with EC50 values ranging from 16.3 to 85.8 μM.

scholarly journals Anti-inflammatory Anthraquinones from the Crinoid Himerometra magnipinna

2015 ◽  
Vol 10 (2) ◽  
pp. 1934578X1501000
Author(s):  
Yen-You Lin ◽  
Su-June Tsai ◽  
Michael Y. Chiang ◽  
Zhi-Hong Wen ◽  
Jui-Hsin Su
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Absolute Configuration ◽  
Spectroscopic Data ◽  
Test Compound ◽  
X Ray Diffraction ◽  
X Ray ◽  
Anti Inflammatory ◽  
Raw264.7 Macrophage

Chemical investigation of a crinoid Himerometra magnipinna has afforded three anthraquinones (1–3), including one new metabolite, (+)-rhodoptilometrin (1). The structures of these compounds were elucidated on the basis of their spectroscopic data and the absolute configuration of 1 was further confirmed by single-crystal X-ray diffraction analysis. In the in vitro anti-inflammatory effects test, compound 2 was found to significantly inhibit the accumulation of the pro-inflammatory iNOS protein of the LPS-stimulated RAW264.7 macrophage cells.

scholarly journals Enzyme-catalyzed kinetic resolution of N-Boc-trans-3-hydroxy-4-phenylpyrrolidine

2014 ◽  
Vol 12 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ferenc Faigl ◽  
Ervin Kovács ◽  
Dóra Balogh ◽  
Tamás Holczbauer ◽  
Mátyás Czugler ◽  
...  
Keyword(s):  
Single Crystal ◽  
Absolute Configuration ◽  
Kinetic Resolution ◽  
Diffraction Method ◽  
Pure Form ◽  
X Ray Diffraction ◽  
Resolution Method ◽  
X Ray ◽  
Temperature Optimization ◽  
Acetate Derivative

AbstractThe first enzyme-catalyzed kinetic resolution of tert-butyl-3-hydroxy-4-phenylpyrrolidine-1-carboxylate is presented. Enzyme, solvent and temperature optimization resulted in a new resolution method with E = 40 enantioselectivity. The acetate derivative of the (+)-(3S,4R) enantiomer formed while the (−)-(3R,4S) isomer remained intact. Very good enantioselectivities (E > 200) were achieved in the enzyme-catalyzed alcoholysis of the racemic acetate in i-propanol and t-butanol where the (+)-(3S,4R) enantiomer was prepared in pure form (ee > 99.7%). Absolute configuration of the (−)-(3R,4S)-enantiomer was determined by single crystal X-ray diffraction method.

Euryachins A and B, a new type of diterpenoids from Eurya chinensis with potent NO production inhibitory activity

RSC Advances ◽  
2016 ◽  
Vol 6 (89) ◽  
pp. 85958-85961 ◽  
Author(s):  
Jia-Ling Song ◽  
Yao Yuan ◽  
Hai-Bo Tan ◽  
Jie-Wei Wu ◽  
Ri-Ming Huang ◽  
...  
Keyword(s):  
Single Crystal ◽  
Absolute Configuration ◽  
Inhibitory Activity ◽  
No Production ◽  
X Ray Diffraction ◽  
X Ray ◽  
New Type ◽  
The Absolute

Euryachins A (1) and B (2), new typediterpenoid euryamanes, were isolated from the branches of Eurya chinensis. The absolute configuration of 1 was determined by single-crystal X-ray diffraction. Both 1 and 2 exhibited significant NO production inhibitory activity.

Heterocladol, a halogenated selinane sesquiterpene of biosynthetic significance from the red alga Laurencia filiformis: Its isolation, crystal structure andabsolute configuration

1977 ◽  
Vol 30 (12) ◽  
pp. 2679 ◽  
Author(s):  
R Kazlauskas ◽  
PT Murphy ◽  
RJ Wells ◽  
JJ Daly ◽  
WE Oberhansli
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Absolute Configuration ◽  
Red Alga ◽  
Ring Closure ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Annular Ring

The structure and absolute configuration of heterocladol, C15H26BrClO (6), have been determined by single-crystal X-ray diffraction methods. This compound is the first example of a selinane skeleton reported from Laurencia species and its structure can be rationalized in terms of a trans-annular ring closure of a germacradiene. The colourless crystals are monoclinic, space group P21, with a 11.852, b 14.486, c 10.932 Ǻ, β 119.6�, Z4.

scholarly journals Jatroidaine A: a New Tetranortirucallane Type Triterpene from Jatropha multifida

2021 ◽  
Vol 15 (5) ◽  
pp. 408-413
Author(s):  
Fei Li ◽  
Liang Ma ◽  
Jinyuan Zhang ◽  
Xueling Qiao ◽  
Dingshan Zhang ◽  
...  
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Absolute Configuration ◽  
Thioredoxin Reductase ◽  
Spectroscopic Methods ◽  
Significant Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inhibitory Activities ◽  
Jatropha Multifida

Jatroidaine A (1), a new tetranortirucallane-type triterpene, and two known analogues (2−3) were isolated from the leaves and branches of Jatropha multifida. Their structures were fully elucidated by extensive spectroscopic methods and comparison to known compounds. The absolute configuration of 1 was assigned by single-crystal X-ray diffraction analysis. All compounds were evaluated for their anti-inflammatory and thioredoxin reductase (TrxR) inhibitory activities. Unfortunately, no significant activity was observed.

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