# Theoretical investigations of free energy of binding and chiral recognition studies of (R)- and (S)-Noradrenaline towards β-cyclodextrin.
> β-シクロデキストリンに対する(R)体および(S)体ノルアドレナリンの結合自由エネルギーとキラル認識に関する理論的研究


## Abstract

This computational study examined the inclusion complexes formed between the R and S enantiomers of noradrenaline (NA), a catecholamine relevant to Parkinson's disease, and β-cyclodextrin (β-CD), a widely used drug carrier. AutoDock calculations yielded binding free energies of -4.81 kcal/mol for S-NA and -4.53 kcal/mol for R-NA within the β-CD cavity. Geometry optimization using the ONIOM2 (B3LYP/6-31g++DP:PM6) method in Gaussian software showed that the S-NA/β-CD complex (-56.48 kcal/mol) was more stable than R-NA/β-CD (-54.59 kcal/mol). Molecular dynamics simulations confirmed greater hydrogen bond stability for the S-NA complex. Thermodynamic properties, IR vibrational analysis, HOMO-LUMO gap energies, and conformational analysis further supported the preferential stability of S-NA inclusion. These theoretical findings aligned with published NMR experimental data, providing insight into chiral separation and drug delivery applications.

### Mechanism

S-noradrenaline forms more intermolecular hydrogen bonds within the β-cyclodextrin cavity than the R-enantiomer, resulting in greater thermodynamic stability of the inclusion complex and preferential chiral recognition of the S-form.

## Bibliographic

- **Authors**: Karthikeyan M, Dhinesh Kumar M, Kaniraja G, Karunakaran C
- **Journal**: J Mol Graph Model
- **Year**: 2023
- **PMID**: [37379759](https://pubmed.ncbi.nlm.nih.gov/37379759/)
- **DOI**: [10.1016/j.jmgm.2023.108552](https://doi.org/10.1016/j.jmgm.2023.108552)
- **Study type**: in vitro study
- **Delivery route**: in vitro
- **Effect reported**: not assessed

## Delivery context

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 37379759. https://h2-papers.org/en/papers/37379759
> **Source**: PubMed PMID [37379759](https://pubmed.ncbi.nlm.nih.gov/37379759/)