General and versatile approach to the synthesis of optically active 5-alkylpiperazine-2-carboxylic acids
General and convenient syntheses of optically active 5-alkylpiperazine-2-carboxylic acids are described. The methods are based on cyclization of L- or D-serine with α-amino acids and occur without loss of optical purity. The presented procedures are based
BETA-SECRETASE INHIBITING COMPOUNDS HAVING OXO-DIHYDRO-PYRAZOLE MOIETY
Disclosed are compounds represented by Formula (I) as defined in the specification, or pharmaceutically acceptable salts or isomers thereof, and a pharmaceutical composition for inhibiting beta-secretase activity comprising a therapeutically effective amo
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(2009/04/25)
Chiral Ligands Containing Heteroatoms. 11. Optically Active 2-Hydroxymethyl Piperazines as Catalyst in the Enantioselective Addition of Diethylzinc to Benzaldehyde
Starting from enantiomerically pure serine, a series of (2R,5S) and (2S,5S)-2-hydroxymethyl-5-alkyl piperazines 1-5 were prepared in good yields without any racemization.The use of these compounds as chiral catalysts for the enantioselective addition of d