Computational Chemistry in Drug Development Program

Computational chemistry methods for the purpose of design of new molecules, especially for drug compounds, as well as the prediction of physico-chemical properties has become the method of choice for a majority of the pharmaceutical industry with regard to development and drug discovery. Application method is also called in silico this, starting from the basic postulates of classical drug design paradigm that states that the effect of the drug in the human body is a consequence of "molecular recognition" between the ligand (in this case obatdan sutau macromolecules (target).

Pharmacological activity of the ligand to its holder (site of action) is determined by the arrangement of space and the electron density of atoms ligands, and also how the atoms interact with the target molecule or "biological conterpart" (Bohm & Klebe, 1996). The structure, dynamics, and interactions thus allowing a characterization using computational chemistry done. For example, molecular mechanics based approach (molecular mechanics) can efficiently help the discovery of new drug candidates, and methods of computation are not expensive are now routinely used in drug design (Jorgensen, 2004).

However, if the description of the nature of electrons needed for design purposes, then the use of quantum mechanics very beperan. Indeed approach to quantum mechanics-based computational chemistry in addition to explaining the effects of quantum electronics, is also able to explain the formation and breaking of chemical bonds, securities polarisai, transfer cargo, etc., Are usually able to more accurately estimate the energy molecules (Cavali et al., 2006). Application of quantum mechanics-based ligands in drug design since the first observation has been directed in the energy, geometry, and distribution of electrons (eg HOMO, LUMO, dipole moment, and so on.) Small organic molecules. Calculations of quantum mechanics routinely has also performed in the analysis of QSAR (Quantitative Structure-Activity Relationship) classic (Lepp & Chuman, 2005), 3D QSAR (Aguirre et al., 2005) and also develop quantum descriptors (Wan et al., 2004) for use in the study of structure-activity correlations.

It is interesting in computational chemistry use associated with target molecules in drug design is the study of the analysis of enzymatic reactions in biological systems which have a pharmacological relevance (Gogonea et al., 2001), this simulation allows to explain the mechanism of substrate (inhibitor) -enzim and further towards interaction enzyme substrate in the transition state through the analysis of the binding energy (binding energy).