Changes between Dragon 5.4 and Dragon 5.5

In Dragon 5.5 two new blocks of molecular descriptors were added, leading to a total of 1560 (780x2) new descriptors.

The new block 21 is comprised of 2D binary fingerprints, which define the presence (1) or absence (0) of specific atom pairs at different topological distances (from 1 to 10).

The new block 22 is comprised of 2D frequency fingerprints, which differ from the binary fingerprints since the frequency of specific atom pairs at different topological distances (from 1 to 10) is calculated instead of the simple atom pair number.

The considered atom pairs are all of the possible combinations of C, N, O, S, P, F, Cl, Br, I, B, Si and X (where X represents any other atom, except for hydrogen).