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Determination of the Chemical Structure of novel colored 1 H ‐pyrrol‐3(2 H )‐one derivatives formed by Maillard ‐type reactions
Author(s) -
Hofmann Thomas
Publication year - 1997
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19970800608
Subject(s) - chemistry , maillard reaction , atropisomer , pyrrole , acetic acid , two dimensional nuclear magnetic resonance spectroscopy , stereochemistry , aqueous solution , tautomer , nuclear magnetic resonance spectroscopy , ring (chemistry) , furan , spectroscopy , organic chemistry , physics , quantum mechanics
The determination of the chemical structure of a previously unknown Maillard reaction product with an amino acid incorporated in a four‐ring structure is reported. The red compounds 1a and 1b , isolated from a thermally treated aqueous solution of furan‐2‐carbaldehyde and L‐alanine, were identified as ( S )‐4{( E )‐1‐formyl ‐2‐(2‐furyl)ethenyl}‐5‐(2‐furyl)‐2‐{( E )‐(2‐furyl)methylidene}‐2, 3‐dihydro‐α‐methyl‐3‐oxo‐1 H ‐pyrrole‐1‐acetic acid and its 2‐{( Z )‐(2‐furyl)methylidene}isomer, respectively, by several 1D‐ and 2D‐NMR techniques, MS, UV, and IR spectroscopy as well as by synthetic experiments. 2D‐NOESY and 2D‐ROESY experiments performed for conformation analysis indicated the existence of two atropisomers.