Crystal Structure of the Native Sesquiterpene Lactone Arctolide

1993 ◽  
Vol 58 (4) ◽  
pp. 909-917 ◽  
Author(s):  
Urszula Rychłewska ◽  
Beata Szczepanska ◽  
Miloš Buděšínský ◽  
David Šaman ◽  
Soňa Vašíčková ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Sesquiterpene Lactone ◽  
Hydroxy Group ◽  
Structure Analysis ◽  
Relative Configuration ◽  
X Ray

X-Ray structure analysis of the native sesquiterpenic arctolide (I) was performed. The results gave evidence that the relative configuration of the hydroxy group at C(3) in the initially suggested arctolide formula (II) has to be corrected to β. Related to this modification, formulas of some other native lactones and derivatives which had been corelated with arctolide before were also corrected.

X-ray crystal structure analysis of parthenin–A sesquiterpene lactone

1994 ◽  
Vol 29 (3) ◽  
pp. 373-378 ◽  
Author(s):  
Vivek K. Gupta ◽  
K. N. Goswami ◽  
K. K. Bhutani
Keyword(s):  
Crystal Structure ◽  
Sesquiterpene Lactone ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
X Ray

1,3-Dipolar [3+3] Cycloaddition of 1,4-Benzodiazepinone-Based Nitrones with α-Halohydroxamates for Diastereoselective Synthesis of Novel d-Edge Heterocycle-Fused 1,4-Benzodiazepinones

Synlett ◽  
2021 ◽  
Author(s):  
Hong-Wu Zhao ◽  
Heng Zhang ◽  
Lu-Yu Cai ◽  
Zhe Tang ◽  
Xiao-Zu Fan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Reaction Mechanism ◽  
Single Crystal ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Diastereoselective Synthesis ◽  
Reaction Conditions ◽  
Relative Configuration ◽  
X Ray ◽  
Single Crystal Structure Analysis

Promoted by K2CO3 (2.0 equiv), the 1,3-dipolar [3+3] cycloaddition between 1, 4-benzodiazepinone-based nitrones and α-halohydroxamates processed smoothly under the mild reaction conditions and delivered structurally novel and complex cis or trans-configured d-edge-heterocycle-fused 1,4-benzodiazepinones in up to >99% isolated yield with >20:1 dr. The relative configuration of the title chemical entities was clearly identified with the use of X-ray single crystal structure analysis. The reaction mechanism was assumed to interpret the diastereoselective production of the obtained cis or trans-configured d-edge-heterocycle-fused 1, 4-benzodiazepinones.

Synthesis and X-Ray Crystal Structure of Cynandione B Analogues

2012 ◽  
Vol 65 (1) ◽  
pp. 58 ◽  
Author(s):  
Lisa P. T. Hong ◽  
Jonathan M. White ◽  
Christopher D. Donner
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Structural Requirements ◽  
Relative Configuration ◽  
X Ray ◽  
One Step ◽  
The One

The synthesis of analogues of cynandione B, a phenolic acetophenone from Cynanchum taiwanianum, is described. The one-step conversion of benzochromenones to the heptacyclic spiroacetal core of cynandione B using methylmagnesium bromide is investigated and structural requirements for this novel transformation established. X-ray crystal structure analysis has established the relative configuration in these unusual heterocycles.

Synthesis of morphan derivatives with additional substituents in 8-position

2016 ◽  
Vol 71 (10) ◽  
pp. 1057-1069
Author(s):  
Janine Stefaowitz ◽  
Dirk Schepmann ◽  
Constantin Daniliuc ◽  
Susumu Saito ◽  
Bernhard Wünsch
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Primary Amine ◽  
Crystal Structure Analysis ◽  
One Pot ◽  
Relative Configuration ◽  
X Ray ◽  
Major Interest ◽  
System 2 ◽  
Sequential Transformation

AbstractThe morphan system (2-azabicyclo[3.3.1]nonane) as a substructure of morphine is of major interest in medicinal chemistry. Herein, the synthesis of morphan derivatives with additional substituents at the propano bridge is reported. In order to avoid the isolation of the smelly and volatile nitrile 6 and the very polar primary amine 9, an efficient one-pot, three-step sequential transformation of the mesylate 5 into amides 10 was developed. The key step of the synthesis was the stereoselective intramolecular opening of the epoxides 11a–d leading to the exo-configured 8-hydroxymorphans 12a–d. The configuration of the exo-configured hydroxymorphan 12d bearing the κ- and σ-pharmacophoric 3,4-dichlorophenylacetyl moiety was inverted by oxidation and stereoselective reduction. An X-ray crystal structure analysis of the benzamide 12c confirmed the relative configuration of the hydroxymorphans 12a–d and 14d.

scholarly journals Preparative-scale HPLC Resolution of Metallacyclic η3-Allyltricarbonyliron Complexes and Determination of the Absolute Configuration by X-Ray Crystal Structure Analysis

1999 ◽  
Vol 23 (9) ◽  
pp. 578-579
Author(s):  
Rainer Schobert ◽  
Hermann Pfab ◽  
Jutta Böhmer ◽  
Frank Hampel ◽  
Andreas Werner
Keyword(s):  
Crystal Structure ◽  
Silica Gel ◽  
Structure Analysis ◽  
Absolute Configuration ◽  
Crystal Structure Analysis ◽  
Preparative Scale ◽  
X Ray ◽  
The Absolute

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.

Second-Generation Inhibitors for the Metalloprotease Neprilysin Based on Bicyclic Heteroaromatic Scaffolds: Synthesis, Biological Activity, and X-Ray Crystal-Structure Analysis

2005 ◽  
Vol 88 (4) ◽  
pp. 731-750 ◽  
Author(s):  
Stefan Sahli ◽  
Brian Frank ◽  
W. Bernd Schweizer ◽  
François Diederich ◽  
Denise Blum-Kaelin ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Biological Activity ◽  
Structure Analysis ◽  
Second Generation ◽  
Crystal Structure Analysis ◽  
X Ray
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