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Beyond Rotatable Bond Counts: Capturing 3D Conformational Flexibility in a Single Descriptor.

ABSTRACT: A new molecular descriptor, nConf₂₀, based on chemical connectivity, is presented which captures the accessible conformational space of a molecule. Currently the best available two-dimensional descriptors for quantifying the flexibility of a particular molecule are the rotatable bond count (RBC) and the Kier flexibility index. We present a descriptor which captures this information by sampling the conformational space of a molecule using the RDKit conformer generator. Flexibility has previously been identified as a key feature in determining whether a molecule is likely to crystallize or not. For this application, nConf₂₀ significantly outperforms previously reported single-variable classifiers and also assists rule-based analysis of black-box machine learning classification algorithms.

SUBMITTER: Wicker JG

PROVIDER: S-EPMC5271572 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Beyond Rotatable Bond Counts: Capturing 3D Conformational Flexibility in a Single Descriptor.

Wicker Jerome G P JG Cooper Richard I RI

Journal of chemical information and modeling 20161206 12

A new molecular descriptor, nConf<sub>20</sub>, based on chemical connectivity, is presented which captures the accessible conformational space of a molecule. Currently the best available two-dimensional descriptors for quantifying the flexibility of a particular molecule are the rotatable bond count (RBC) and the Kier flexibility index. We present a descriptor which captures this information by sampling the conformational space of a molecule using the RDKit conformer generator. Flexibility has ...[more]

PMID: 28024401

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