# Crystal structure of an apremilast ethanol hemisolvate hemihydrate solvatomorph.
> アプレミラスト・エタノール半溶媒和物・半水和物の結晶構造解析


## Abstract

This study reports the crystallographic characterization of a novel solvatomorphic form of apremilast (AP), a phosphodiesterase 4 (PDE4) inhibitor. The asymmetric unit comprises one AP molecule along with disordered ethanol and water molecules, each at half occupancy. The dihedral angle formed between the phenyl and isoindole ring planes was determined to be 67.9°. Both intramolecular and intermolecular hydrogen bonding networks were found to contribute to the stabilization of the molecular conformation and the maintenance of crystal packing. This structural characterization provides insight into the solid-state properties of a pharmaceutically relevant compound.

## Bibliographic

- **Authors**: Wu Y, Liu X, Xu J, Zhang S, Shen K, Sun LI, et al.
- **Journal**: Acta Crystallogr E Crystallogr Commun
- **Year**: 2017 (2017-06-01)
- **PMID**: [28638635](https://pubmed.ncbi.nlm.nih.gov/28638635/)
- **DOI**: [10.1107/S2056989017006661](https://doi.org/10.1107/S2056989017006661)
- **PMC**: [PMC5458300](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458300/)
- **Study type**: other
- **Delivery route**: not specified
- **Effect reported**: not assessed

## Delivery context

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (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)

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> **Cite as**: H2 Papers — PMID 28638635. https://h2-papers.org/en/papers/28638635
> **Source**: PubMed PMID [28638635](https://pubmed.ncbi.nlm.nih.gov/28638635/)