Work

Pregabalin Cocrystals with Carboxylic Acid: Structural and Thermal Analyses

Year: 2025

Type: article

Abstract: Cocrystals of pregabalin (PGB) with different carboxylic acids were developed, and their crystal structures were determined by single crystal X-ray diffraction. All obtained cocrystal structures were isostructural and related to the free PGB crystal structure (PGB_AN). These structural similarities result in analogous thermal behavior: upon heating, cocrystals segregate, with PGB_AN as one of the final products. Notably, cocrystals formed with octanoic acid exhibited multiple single crystal to single crystal phase transitions upon heating. Initially, the 1:1 stoichiometric sample exhibited a disproportion transition at 44 °C. As a result, the single crystal is a new cocrystal of 1:2 stoichiometry. Further heating induced segregation, ultimately yielding a PGB_AN single crystal. Similar behavior was observed in cocrystals with decanoic acid, but a different structure is observed in the 1:2 stoichiometry cocrystal.

Source: Crystal Growth & Design

DOI: 10.1021/acs.cgd.4c01736

Authors: Pablo E. Gaztañaga, Eleonora Freire Espeleta, Daniel R. Vega

Institutions: China Nuclear Energy Association, Consejo Nacional de Investigaciones Científicas y Técnicas, National University of General San Martín

Language: English

Topic: Crystallography and molecular interactions

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

OpenAlex ID: W4408203604

FWCI: 1.353

Cites: 28

Cited by: 3

Related to: 10