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Antiasthma Drugs: Methylxanthines

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Related Experiment Video

Updated: Jun 1, 2026

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis

Published on: November 17, 2011

Theophylline-gentisic acid (1/1).

Srinivasulu Aitipamula, Pui Shan Chow, Reginald B H Tan

Acta Crystallographica. Section E, Structure Reports Online

|May 18, 2011

Summary

This summary is machine-generated.

This study details a novel cocrystal formed by the anti-asthma drug theophylline and the anti-inflammatory drug gentisic acid. This pharmaceutical cocrystal, involving two active ingredients, presents an unexplored area in drug development.

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Last Updated: Jun 1, 2026

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis

Published on: November 17, 2011

Area of Science:

Crystallography
Pharmaceutical Science
Materials Science

Background:

Theophylline is an anti-asthmatic drug, and gentisic acid is a non-steroidal anti-inflammatory drug.
Pharmaceutical cocrystals are crystalline solids composed of two or more different molecules in a defined stoichiometric ratio.
Cocrystals involving two active pharmaceutical ingredients (APIs) are relatively unexplored.

Purpose of the Study:

To synthesize and characterize a novel 1:1 cocrystal of theophylline and gentisic acid.
To investigate the crystal structure and intermolecular interactions within the cocrystal.
To explore the potential of dual-API cocrystals in pharmaceutical applications.

Main Methods:

Cocrystallization of theophylline and gentisic acid.
Single-crystal X-ray diffraction analysis to determine the crystal structure.
Analysis of hydrogen bonding and π-π stacking interactions.

Main Results:

A 1:1 cocrystal of theophylline (C7H8N4O2) and gentisic acid (C7H6O4) was successfully formed.
The crystal structure revealed two-dimensional hydrogen-bonded sheets stabilized by N-H⋯O and O-H⋯N interactions.
Significant π-π stacking interactions were observed between the purine and benzoic acid rings, with a centroid-centroid distance of 3.348(1) Å.

Conclusions:

The formation of a dual-API cocrystal between theophylline and gentisic acid demonstrates a viable strategy for creating new pharmaceutical forms.
The characterized hydrogen bonding and π-π stacking interactions are crucial for the stability of this cocrystal.
This work highlights the potential of exploring dual-API cocrystals as a novel area in pharmaceutical research and development.