Title:A Rational Approach to Anticancer Drug Design: 2D and 3D- QSAR,
Molecular Docking and Prediction of ADME Properties using Silico
Studies of Thymidine Phosphorylase Inhibitors
Volume: 20
Issue: 2
Author(s): Vaibhav V. Raut*, Shashikant V. Bhandari, Shital M. Patil and Aniket P. Sarkate
Affiliation:
- Department of Pharmaceutical Chemistry, A.I.S.S.M.S College of Pharmacy, near RTO, Kennedy Road, Pune-411001,
Maharashtra, India
Keywords:
Phosphorylase inhibitions, structure-activity relationship, oxadiazole-isatin hybrid, docking, ADME, anticancer.
Abstract:
Background: Cancer is the most prevalent disease seen nowadays. Thymidine phosphorylase
(TP) is an angiogenic enzyme that is overexpressed in many solid tumors. Over the years, Thymidine
phosphorylase has emerged as a novel target for anticancer drug development as an inhibitor.
Objective: To design novel oxadiazole-isatin pharmacophore-containing molecules and explore their
structural requirements related to the anticancer activity.
Methods: Pharmacophore optimisation was carried out for oxadiazole-isatin hybrid molecules using molecular
modeling studies (2D and 3D QSAR). Further, the new chemical entities were designed using the
combilib tool of V life software. To have a better understanding of the binding interactions, the newly
designed molecules were docked. To achieve a drug-like pharmacokinetic profile, molecules were also
tested for ADME prediction.
Results: Two-Dimensional Quantitative Structure-Activity Relationship (2D-QSAR) model was generated
using the multiple regression method with r2 = 0.84 and q2 = 0.76. Three-Dimensional Quantitative
Structure-Activity Relationship (3D-QSAR) model was obtained by simulated annealing k nearest near
(SA kNN) method with q2 = 0.8099. Molecular docking studies showed promising results. Compound 5
was found to be with the best dock score and the best fit to the active site pocket of the thymidylate phosphorylase
enzyme. The compounds have notable absorption, distribution, metabolism, and excretion
(ADME) properties that can be predicted to assure a drug-like pharmacokinetic profile.
Conclusion: One of the most successful and fast-increasing methodologies is molecular modeling. It not
only aids in the prediction of specific target compounds but also aids in the cost reduction of valuable
substances. The successful use of molecular modeling was done in this study, with caution taken to avoid
any chance co-relation. Optimised pharmacophore was obtained and new chemical entities were designed.
Docking studies revealed that Compound 5 has shown better H-bond interaction with Lys 221 and Thr
151 with bond distances 2.0 Α° and 1.8 Α° which is the most active molecule. ADME tests discovered
that the majority of the newly designed compounds were within a reasonable range as required in a druglike
pharmacokinetic profile. Molecules 2, 4, 5, 6 can be considered as a lead for future synthesis and
biological screening.