1 CSF Cytidine-5'-monophosphate-3-fluoro-N-acetyl-neuraminic acid 1.000 2 NCC Cytidine-5'-monophosphate-5-N-acetylneuraminic acid 0.976 3 FN5 Cmp-3f(a)-neu5ac 0.929 4 CMK Cytidine 5'-monophosphate 3-deoxy-beta-D-gulo-oct-2-ulo-pyranosonic acid 0.814