Page 139 - Chiral Separation Techniques

116 4 CHIRBASE: Database Current Status and Derived Research Applications using …

Fig. 4-13. Plot of map luminance versus mean similarity of molecule sets.

The results obtained are in accordance with our previous observations:
Chiralcel OD and Chiralpak AD are associated with the largest mean values of
molecular diversity.
Whelk-O 1 and Pirkle DNBPG have appreciable differences in terms of applica-
tion range. This is not surprising since Pirkle DNBPG often requires a prior
derivatization of solutes to achieve a separation. This also confirms the atypical
character of Whelk-O 1 compared to other Pirkle-like CSPs.
Crownpak CR(+) exhibits the lowest diversity of structural features.
For comparative purposes, Chiralcel OD and Crownpak CR could be used as an
extreme case to delineate the basis of a molecular diversity scale.

4.6.2 Comparison of Molecule Dataset Similarities between two CSPs

In the following studies, the same computational steps have been used in a straight-
forward manner as before to compare pairs of CSP. The molecule datasets employed
in these studies are the same as that used above. In addition, two protein-based CSP
were also compared:
Chiral-AGP: alpha-acid glycoprotein bonded to silica.
Ultron ES-OVM: ovomucoid-conjugated bonded to aminopropyl-silica.