Determination of the Absolute Configuration of 19-OH-(-)-Eburnamonine Using a Combination of Residual Dipolar Couplings, DFT Chemical Shift Predictions, and Chiroptics

19-OH-(-)-eburnamonine 1 is a new indole alkaloid isolated from Bonafusia macrocalyx. A natural derivative from (-)-eburnamonine for which absolute configuration and conformation has been determined by making use of residual dipolar couplings enhanced NMR, circular dichroism spectra and high-level computations.

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Relative configuration of micrograms of natural compounds using proton residual chemical shift anisotropy

Nature Communications ◽

10.1038/s41467-020-18093-5 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Nilamoni Nath ◽

Juan Carlos Fuentes-Monteverde ◽

Dawrin Pech-Puch ◽

Jaime Rodríguez ◽

Carlos Jiménez ◽

...

Keyword(s):

Chemical Shift ◽

Residual Dipolar Couplings ◽

Chemical Shift Anisotropy ◽

Dipolar Couplings ◽

Structural Determination ◽

Proton Proton ◽

Relative Configuration ◽

Similar Information ◽

3D Molecular Structure

Abstract 3D molecular structure determination is a challenge for organic compounds or natural products available in minute amounts. Proton/proton and proton/carbon correlations yield the constitution. J couplings and NOEs oftentimes supported by one-bond 1H,13C residual dipolar couplings (RDCs) or by 13C residual chemical shift anisotropies (RCSAs) provide the relative configuration. However, these RDCs or carbon RCSAs rely on 1% natural abundance of 13C preventing their use for compounds available only in quantities of a few 10’s of µgs. By contrast, 1H RCSAs provide similar information on spatial orientation of structural moieties within a molecule, while using the abundant 1H spin. Herein, 1H RCSAs are accurately measured using constrained aligning gels or liquid crystals and applied to the 3D structural determination of molecules with varying complexities. Even more, deuterated alignment media allow the elucidation of the relative configuration of around 35 µg of a briarane compound isolated from Briareum asbestinum.

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Determination of the absolute configuration of natural products

Chinese Journal of Natural Medicines ◽

10.3724/sp.j.1009.2013.00193 ◽

2014 ◽

Vol 11 (3) ◽

pp. 193-198 ◽

Cited By ~ 15

Author(s):

Ling-Yi KONG ◽

Peng WANG

Keyword(s):

Natural Products ◽

Absolute Configuration ◽

The Absolute

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Rapid Organocatalytic Chirality Analysis of Amines, Amino Acids, Alcohols, Amino Alcohols and Diols with Achiral Iso(thio)cyanate Probes

Chemical Science ◽

10.1039/d1sc02061g ◽

2021 ◽

Author(s):

Eryn Nelson ◽

Jeffrey S. S. K. Formen ◽

Christian Wolf

Keyword(s):

Amino Acids ◽

Absolute Configuration ◽

Rapid Determination ◽

Amino Alcohols ◽

Enantioselective Synthesis ◽

Widespread Occurrence ◽

Chiral Compounds ◽

New Methods ◽

The Absolute

The widespread occurrence and significance of chiral compounds does not only require new methods for their enantioselective synthesis but also efficient tools that allow rapid determination of the absolute configuration,...

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

Journal of Chemical Research ◽

10.1177/174751989902300930 ◽

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.

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