Optibrium

We've built and validated QSAR models of seven physicochemical property endpoints, based on data made available by the US Environmental Protection Agency as part of its Toxicity Evaluation Software Tool (T.E.S.T.) package. The models were built with StarDrop’s Auto-Modeller module and are available to all StarDrop users free-of-charge.

These two models calculates the number of sp3 carbons and the total number of carbons compound. These are available to enable the calculation of properties such as saturation - the ratio of sp3 carbons to the total number of carbons (Lovering F, Bikker J, Humblet C. Escape from flatland: increasing saturation as an approach to improving clinical success. J Med Chem 2009, 52:6752–6756.). They suggest that the typical levels of saturation increase from 0.36 in drug discovery through to 0.47 in drugs.

When installed, each will appear in StarDrop in the "Models" tab alongside the ADME QSAR models and other simple properties as a "Custom" model, allowing it to be calculated easily for any data set. If you've not used custom models before, details on how to install it are available on the following pages, along with the model file...

This calculates the number of aromatic rings in a compound. This has been proposed by Ritchie and Macdonald as a characteristic that is inidcative of the developability of a compound (Ritchie and Macdonald (2009), Drug Discov. Today 14 pp. 1011-1020). They suggest that greater than three aromatic rings increases correlates with poorer compound developability and an increased risk of attrition in development.

When installed, this will appear in StarDrop in the "Models" tab alongside the ADME QSAR models and other simple properties as a "Custom model", allowing it to be calculated easily for any data set. If you've not used custom models before, details on how to install it are available on the following pages, along with the model file...

We've built and validated QSAR models of seven key toxicity endpoints, based on data made available by the US Environmental Protection Agency as part of its Toxicity Evaluation Software Tool (T.E.S.T.) package. The models were built with StarDrop’s Auto-Modeller module and are available to all StarDrop users free-of-charge.

This calculates the "exact mass" of a molecule based upon the masses of the most abundant isotopes of its substituent atoms. As such, this calculation will often be slightly different to the molecuar weight calculation which is based upon average isotopic distributions. When installed, this will appear in StarDrop in the "Models" tab alongside the ADME QSAR models and other simple properties as a "Custom model", allowing it to be calculated easily for any data set. If you've not used custom models before, details on how to install it are available on the following pages, along with the model file...

This "model" provides a count of the number of heavy atoms (i.e. not hydrogen) in a molecule. While labelled "model" this calculation is merely a simple property, but when installed will appear in StarDrop in the "Models" tab alongside the ADME QSAR models and other simple properties as a "Custom model", allowing it to be calculated easily for any data set. If you've not used custom models before, details on how to install it are available on the following pages, along with the model file...

In J. Med. Chem., 2000, 43 (20), pp 3714–3717, Ertl et al. propose the calculation of two polar surface area values, the first reports the PSA for Nitrogen and Oxygen atoms only, the second also includes Sulfur and Phosphorus in the calculation.

The default TPSA model in StarDrop is the first of these models, including only N and O. This was chosen based on feedback from users. However, we have also created a StarDrop model for the more general model for those who wish to use this definition. Instructions on how to download and install the model are available on the following pages, along with the model file itself...

This model predicts aquatic toxicity of a compound against Tetrahymena pyriformis expressed as pIGC₅₀ (=-log IGC₅₀). Built using the StarDrop Auto-Modeller, this model is based upon literature data and can be downloaded and used with StarDrop 4.2 and onwards. If you've not used custom models before, details on how the model was built and how to install it are available on the following pages, along with the model file...

This model is based upon the following work published by Pearce et al.

Pearce BC, Sofia MJ, Good AC, Drexler DM, Stock DA. An empirical process for the design of high-throughput screening deck filters. J Chem Inf Model. 2006;46:1060–1068.

Based upon the data published, this model can be downloaded and used with StarDrop 4.2 and onwards. If you've not used custom models before, details on how the model was built and how to install it are available on the following pages, along with the model file itself...