In a study of 124 falcipain inhibitors, Open3DQSAR processed CoMFA and CoMSIA interaction fields originally generated in SYBYL and produced models that achieved cross‑validated q² values of 0.810 for CoMFA and 0.586 for CoMSIA. The external validation gave r²_pred values of 0.946 and 0.662, respectively, confirming the robustness of the approach. Notably, the q² for CoMFA processed by Open3DQSAR was considerably higher than that obtained directly from SYBYL, indicating that the same raw fields can yield different results depending on the chemometric engine and variable selection method used.
+-------------------------------------------------------------+ | 3D-QSAR Computational Workflow | +-------------------------------------------------------------+ | v [ Molecular Alignment ] ---> Uses Open3DALIGN to superimpose ligands | v [ MIF Computation ] ---> Generates Steric & Electrostatic fields | v [ Data Pretreatment ] ---> Cutoffs, SD-Filtering, Variable reduction | v [ PLS Chemometrics ] ---> Partial Least Squares regression modeling | v [ Visualization ] ---> Exports 3D contour maps to PyMOL/Maestro open3dqsar
Maps the shape, size, and physical boundaries of a ligand. In a study of 124 falcipain inhibitors, Open3DQSAR
A key feature is the software's user‑friendly interface to major quantum mechanical packages, including Gaussian, Firefly, GAMESS‑US, TURBOMOLE, and MOLDEN. This integration allows the calculation of QM electron density and electrostatic potential 3D maps entirely from within Open3DQSAR. Once aligned, the coordinates are loaded into Open3DQSAR
Once aligned, the coordinates are loaded into Open3DQSAR. The software places the molecules inside a virtual 3D grid box. It computes: