ACD/Sigma Batch       Click image to magnify

ACD/Sigma Batch allows you to directly access the Hammett electronic substituent constant, σ, calculated for selected fragments of your molecule or the substituents of your library for large sets of compounds presented in a number of electronic formats.

This permits you to make an in-depth analysis of the steric effects, the hydrophobic constant (the π constant of Hansch), and related phenomena of the various substituents in the molecule of interest.

To make a calculation, either one SDfile, containing a list of substituents, or two SDfiles, describing the core molecule (scaffold) and the library, can be used to generate sigma values.

With ACD/Sigma Batch you can:

• Calculate sigma constants for numerous structures
• Calculate only Inductive and Resonance sigma constants (as an option)
• Work past interruption, and save job to another file
• Output comments and warnings to a file

How ACD/PhysChem Batch: Sigma Module works:

I. Input file

• ACD/ChemFolder database (.CFD)
• SMILES text file (.TXT)
• MDL SDfile (.SDF)*
• ISIS database (.DB)**

*Note: For more detail about this common text data exchange format, please refer to "MDL File Formats" at the MDL Inc. Web site.
**Note: ISIS/Base 2.2 must be installed on the same PC. 

II. Set options:

• Specify the location of an SDfile where the sample substituents for sigma calculation are placed.
• Specify whether the program should calculate only sigma inductive and sigma resonance.

III. Choose to report results to .SDF, .RDF, .CFD, or .TXT files.

ACD/Sigma Batch can be used independently, or as part of ACD/PhysChem Batch which includes modules for batch prediction of other physicochemical parameters such as logP, logD, pK_a, aqueous solubility, and more.

This package is available for Microsoft Windows, SUN, and LINUX platforms, and can run from Windows command line.