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Published on: August 15, 2016
Structural and theoretical-experimental physicochemical study of trimethoprim/randomly methylated-β-cyclodextrin
Daniela Kubota1, Osmir Fabiano Lopes Macedo, George Ricardo Santana Andrade
1Núcleo de Pós-graduação em Química, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, Campus Universitário Prof. José Aloísio de Campos, CEP 49100-000 São Cristovão, SE, Brazil.
Carbohydrate Research
|October 26, 2011
Summary
This study characterizes trimethoprim
Area of Science:
- Pharmaceutical Chemistry
- Supramolecular Chemistry
Background:
- Trimethoprim is an antibiotic.
- Beta-cyclodextrins are used to improve drug solubility and delivery.
Purpose of the Study:
- To structurally characterize the inclusion complex of trimethoprim with randomly methylated beta-cyclodextrin (RAMEB).
- To investigate the inclusion mechanism and stoichiometry.
Main Methods:
- Phase-solubility studies at pH 7.0.
- Stoichiometric determination using the continuous variation method.
- Spectroscopic analysis (FTIR, 1D and 2D 1H NMR).
- Semiempirical molecular modeling.
Main Results:
- A 1:1 stoichiometry was confirmed for the trimethoprim-RAMEB complex.
- Spectroscopic data indicated inclusion of the trimethoprim's trimethoxyphenyl ring within the RAMEB cavity.
- Interactions between trimethoprim and RAMEB's methyl groups were observed.
- Molecular modeling supported the proposed inclusion structure.
Conclusions:
- Trimethoprim forms a 1:1 inclusion complex with randomly methylated beta-cyclodextrin.
- The trimethoprim molecule is primarily included via its trimethoxyphenyl ring.
- This complexation enhances understanding of drug-cyclodextrin interactions for potential pharmaceutical applications.
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