This press release is also available in Spanish.
This research work developed a number of synthetic methodologies for the synthesis of various isoquinolinic alkaloids. They all have in common the use of b-aminoalcohols as the source of chirality operating as auxiliaries or as chiral blocks.
Thus, the employment of (S,S)-(+)-pseudoephedrine as chiral auxiliary enables access to enriched enantiomeric arylglycines, precursors of 3-aryltetrahydroisoquinolines, by means of a synthetic methodology applicable to the stereocontrolled synthesis of such derivatives with a substitution in the 7,8 positions of the aromatic ring of the isoquinolinic nucleus. Also, the aminoalcohol, (S)-(+)- phenylglycinol, has proved to be an efficient chiral building block for access to 1,2-diarylethylamines which, by means of cyclation, lead to optically active 6,7-disubstituted 3-aryltetrahydroisoquinolines.
The convenient manipulation of the synthesised 3-aryltetrahydroisoquinolinic derivatives enabled obtaining a series of chiral berbines, amongst others, (R)-tetrahydropalmatine, (R)-synactine and (S)-xylopinine with high enantiomeric excesses.
Finally, the total synthesis was undertaken of natural aporphinic alkaloid (S)-glaucine employing aminoalcohol (S)-(+)-phenylglycinol as a chiral precursor that helped in the obtention of (S)-laudanosine, on which a process of oxidative coupling was carried out.
Source: Eurekalert & othersLast reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
Published on PsychCentral.com. All rights reserved.
No matter how far you have gone on the wrong road, turn back.
-- Turkish proverb