<p>1.
Approximately
3.7 million (3,700,103) PubChem compounds were used in training the fragment
vectors. Five million compounds (from CID 1 to 5,000,000) were downloaded in
SMILES format from PubChem Download Service<sup>1</sup> for this purpose. Inorganic
part of salts, charges on certain atoms were neutralized, components of mixtures
were split and only one chemical from sets of duplicates were kept. Approximately 100,000 chemicals were held out
for future needs.</p>
<p>2.
Hansen<sup>2</sup>
and Bursi<sup>3</sup> Ames mutagenicity benchmark datasets were used. The data
was preprocessed in the same way as the PubChem chemicals, except in the case
of duplicates, the compound with the highest mutagenicity value was retained, leaving
6771 compounds (3639 mutagenic and 3132 non-mutagenic).</p>
<p>3.
A
dataset of 575 compounds was taken from the publication of Ghose <i>et al</i><sup>4</sup> to compute molar
refractivity of the fragments. </p>
An in-house dataset<sup>5</sup> of 7000 chemicals (Zhu Hao et al) with
their experimentally observed LogP was also used to help in computing LogP
contribution of the fragments.<div><br></div><div>
<p>1.
PubChem
Download Service, URL: https://pubchem.ncbi.nlm.nih.gov/pc_fetch/pc_fetch.cgi.</p>
<p>2.
Hansen,
K., Mika, S., Schroeter, T., Sutter, A., Laak, A. T., Steger-Hartmann, T.,
Heinrich, N. and Müller, K. R. (2009) Benchmark Data Set for in Silico
Prediction of Ames Mutagenicity. J. Chem. Inf. Model. 49, 2077-2081.</p>
<p>3.
Kazius,
J., McGuire, R., Bursi, R. (2005) Derivation and validation of toxicophores for
mutagenicity prediction. J. Med. Chem. 48, 312-320.</p>
<p>4.
Ghose,
A. K., Crippen, G. M. (1987) Atomic physicochemical parameters for
three-dimensional-structure-directed quantitative structure-activity
relationships. 2. Modeling dispersive and hydrophobic interactions. J. Chem.
Inf. Comput. Sci. 27(1), 21-35.</p>
Zhu, H., Sedykh, A., Chakravarti, S. K., Klopman, G.
(2005) A new group contribution approach to the calculation of LogP. Current
Computer-Aided Drug Design 1, 3-9. <br></div>