This is additional material for the papers:

Tomic,S., Gabdoulline,R.R., Kojic-Prodic,B. and R.C.Wade, J.Comput. Aided Mol. Des. (1998) 12, 63-79.

Tomic S., Gabdoulline R. R., Kojic-Prodic B. and Wade R. C., Internet J. Chem, (1998) 1,26. (http://www.ijc.com/articles/1998v1/26/)

*
European Molecular Biology Laboratory, Heidelberg, Germany
*

B. 3D projection of compounds based on their Molecular interaction fields.

Considering 57 compounds, 57*(57-1)/2 pairwise (i,j) distances were defined as
D(i,j) = sqrt(1-SI(i,j)). Then we choose 4 points:

a) Choose points 1 and 2 such that D(1,2) is the largest, all the distances
are simultaneously normalised by this number;

b) Choose point 3 so that the area of triangle formed by points 1,2,3
is the largest;

c) Choose the point 4 so that the area of the tetrahedron formed by points 1,2,3,4
is largest.

These 4 points are assigned 3D coordinates (0,0,0), (1,0,0),
(a,b,0), (c,d,e), where a,b,c,d,e may be computed unambiguously from
the 6 pairwise distances.
All the other compounds are projected onto this 3D space, i.e. assigned
3D coordinates. The points in this chart visualize these coordinates,
based on SI(i,j) for the probes
1 H20 ,
2 NH2+ ,
3 CH3 and
4 O- .