Abstract
New receptors 1-3 that bind stereoselectively amino alcohols and convert chirality of amino acidsvia imine bond formation were synthesized. The receptors have uryl (1), thiouryl (2) and guanidinium (3) groups all with additional phenylcarbonyl motifs, which are effective hydrogen bonding donors and play a key role in the stereoselective recognitions. The stereoselectivities were measured from the integration of 1H NMR peaks. Compound 1 and 2 showed the stereoselectivities for the imine formation with amino alcohols (KR/KS) in the range of 2 ~ 4, and compound 3 in the range of 4 ~ 8. Chirality conversion efficienciesof 1-3 for amino acids, i.e. D/L ratio at equilibrium, are in the range of 1.5 ~ 5.6, showing a little higher efficiency with 3. The additional phenylcarbonyl motifs in 1-3 were revealed not to contribute to significant enhancement of the selectivities.
Original language | English |
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Pages (from-to) | 2938-2942 |
Number of pages | 5 |
Journal | Bulletin of the Korean Chemical Society |
Volume | 30 |
Issue number | 12 |
DOIs | |
State | Published - Dec 2009 |
Keywords
- Amino acid
- Amino alcohol
- Chirality conversion
- Imine receptor
- Stereoselective recognition