402829-07-6Relevant academic research and scientific papers
Synthesis of an optically active, bicyclic 2-pyridone dipeptide mimetic
Dragovich, Peter S.,Zhou, Ru,Prins, Thomas J.
, p. 741 - 746 (2007/10/03)
The eleven-step preparation of the bicyclic 2-pyridone dipeptide mimetic 1 [(3S)-6-(benzyloxycarbonylamino)-5-oxo-l,2,3,5-tetrahydroindolizine-3- carboxylic acid] in optically active form (60% ee) is described. Key steps in the synthesis of I include the osmium-catalyzed asymmetric dihydroxylation of olefin 13 [(6-but-3-enyl-2-methoxypyridin-3-yl)carbamic acid benzyl ester] and the intramolecular cyclization of protected diol 19 [(3'R)-{6-[4'-(tert-butyldimethylsilanyloxy)-3'-hydroxybutyl]-2- methoxypyridin-3-yl}carbamic acid benzyl ester] to afford the pyridinium salt 20 [(3S)-[3-(tert-butyldimethylsilanyloxymethyl)-5-methoxy-2,3-dihydro-1H- indolizin-6-yl]carbamic acid benzyl ester trifuoromethanesulfonic acid salt]. Several alternate methods to prepare olefin 13 are also discussed.
