

| R1 |
: |
aliphatic, aromatic, heterocyclic |
| R2 |
: |
H, aliphatic, aromatic, heterocyclic |
| R-HNL |
: |
R-cyanohydrin synthesizing enzyme ((R )-hydroxynitrile lyase) |
| S-HNL |
: |
S-cyanohydrin synthesizing enzyme ((S )-hydroxynitrile lyase) |

2. Chemical Modification of Chiral Cyanohydrin |
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