Maximizing the stereochemical diversity of spiro-ladder oligomers
Christopher G Levins1, Zachary Z Brown, Christian E Schafmeister
1Department of Chemistry, University of Pittsburgh, Pennsylvania 15260, USA.
Abstract:
[reaction: see text] We introduce all stereoisomers of a bis-amino acid building block derived from trans-4-hydroxy-L-proline. This small library of monomers allows arbitrary stereochemical configuration at any chiral center within our spiro-ladder oligomers. Three tetramer oligomers containing several combinations of the monomers 1-4 were synthesized; we explored the effect of monomer sequence on scaffold conformation by NMR.
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