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Updated: Aug 10, 2026
13:57
Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
Published on: February 18, 2014
Searching for allosteric effects via QSARs
Bioorganic & Medicinal Chemistry
|March 16, 2001
Summary
Quantitative Structure-Activity Relationships (QSARs) revealed 11 instances of inverted parabolic biological activity trends related to molecular refractivity. This suggests larger molecules may alter receptor interactions, impacting drug design.
Area of Science:
- Medicinal Chemistry
- Computational Chemistry
- Pharmacology
Background:
- Quantitative Structure-Activity Relationships (QSARs) are crucial for predicting chemical-biological interactions.
- Molecular refractivity (MR) is a physicochemical property often used in QSAR models.
- Standard QSAR models typically show monotonic relationships between properties and activity.
Purpose of the Study:
- To investigate non-monotonic relationships in QSARs.
- To identify instances of inverted parabolic trends based on molecular refractivity.
- To explore the implications of such trends for drug discovery.
Main Methods:
- Analysis of a database containing 7,000 QSAR models.
- Identification of QSARs exhibiting inverted parabolic relationships with molecular refractivity.
- Examination of biological targets associated with these QSARs, including enzymes and receptors.
Main Results:
- Eleven QSAR models displayed inverted parabolic trends with molecular refractivity.
- These trends were observed for interactions with enzymes (e.g., cyclooxygenase, trypsin) and various receptors.
- Biological activity initially decreased and then increased with rising molecular refractivity.
Conclusions:
- Inverted parabolic QSARs indicate complex structure-activity relationships.
- Larger molecules may induce conformational changes in biological targets, leading to altered interaction modes.
- These findings offer new perspectives for designing molecules with specific biological activities.
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