Multi-Site λ-dynamics for simulated Structure-Activity Relationship studies.

Area of Science:

• Computational chemistry
• Molecular modeling

Background:

• Free energy simulations are crucial for drug design.
• Current methods can be computationally expensive and time-consuming.
• Modeling multiple ligand modifications simultaneously presents a challenge.

Purpose of the Study:

• To introduce and validate Multi-Site Lambda-dynamics (MSλD), a new free energy simulation method.
• To assess the efficacy of MSλD for estimating relative hydration free energies and binding affinities.
• To demonstrate the speed and accuracy improvements of MSλD compared to traditional methods.

Main Methods:

• Development of the Multi-Site Lambda-dynamics (MSλD) method based on λ-dynamics.
• Application of MSλD to model multiple substituents on common ligand cores.
• Validation using test systems including benzene derivatives and HIV-1 reverse transcriptase inhibitors.

Main Results:

• MSλD achieved reliable relative hydration free energy estimates within 0.2 kcal/mol with short trajectories (~1.5 ns).
• MSλD results showed excellent agreement with alchemical free energy simulations (R(2)=0.991) and good agreement with experimental data (R(2)=0.959) for benzene derivatives.
• Estimates of relative binding affinities for HIV-1 inhibitors showed reasonable agreement with traditional methods and experiments (R(2)=0.402).
• MSλD simulations were 20-50 times faster than traditional free energy simulations for comparable accuracy.

Conclusions:

• MSλD is an efficient and accurate method for calculating free energies of molecules with multiple substituents.
• The speed of MSλD makes it suitable for screening large numbers of compounds in drug design.
• MSλD offers a significant advancement in computational chemistry for structure-based drug design applications.