Working with templates

Dragon allows creation of templates that facilitate recursive calculation of molecular descriptors on the basis of the options saved in the template. The template file contains preferences about selection of molecular descriptors and general settings for directories management, descriptor calculation and saving.

 

To generate a template (.drt), preferences for descriptor calculation and saving have to be defined by the menu 'General settings' and the list of molecular descriptors to be calculated has to be defined by the menu 'Select descriptors'. Then, click the item 'Save template' in the menu 'File' of the main menu bar.

 

To load a template, click the item 'Load template' in the menu 'File' of the main menu bar. This operation has to be done before descriptor calculation. After a template has been loaded, only the molecular descriptors provided by the template will be enabled in the window 'Select descriptors'. In any case, the user can add to or delete molecular descriptors from the actual selection before calculation.

 

A default template can be automatically loaded when Dragon starts. In order to define the default template, see the general settings help.

 

The following templates are provided in the folder 'Templates' of the zip file that can be downloaded here: http://www.talete.mi.it/products/dragon_data.zip.. All these templates have the default general settings of Dragon.

 

Dragon 5.5 template

This template is in the file Dragon_5_5.drt. It provides the molecular descriptors that were previously calculated by Dragon 5.5. Only still supported descriptors will be provided and most of them will have the novel symbol defined in Dragon 6.0 (see the 'what's new section' to see which these descriptors are). The total number of descriptors calculated by Dragon 5.5 template is 3193 and not 3224 as in Dragon 5.5. This difference is due to the elimination of some previously defined descriptors.

 

Hydrocarbon template

This template is in the file Dragon_Hydrocarbons.drt. It provides all the descriptors that make sense to calculate when no heteroatoms are present in the molecule dataset. The total number of enabled descriptors is 2635.

 

2D template

This template is in the file Dragon_2D.drt. It provides all the descriptors based only on topological information, such as constitutional descriptors, ring descriptors, topological indices, walk and path counts, connectivity indices, information indices, 2D matrix-based descriptors, 2D autocorrelations, Burden eigenvalues, P_VSA-like descriptors, ETA indices, edge adjacency indices, functional group counts (except for nHBonds), atom-centred fragments, atom-type E-state indices, CATS 2D, 2D atom pairs, molecular properties, and drug-like indices. The total number of enabled descriptors is 3763. This template is particularly useful when molecules are defined in SMILES notation.

 

Standard template

Dragon standard template is in the file Dragon_Standard.drt. It provides the following options and descriptors: all blocks and sub-blocks selected; all the weighting schemes selected. The total number of enabled descriptors is 4885, i.e., all the possible descriptors defined in Dragon.