Detalhes bibliográficos
| Ano de defesa: |
2013 |
| Autor(a) principal: |
Melo, Ariane Carla Campos de
 |
| Orientador(a): |
Martins, Felipe Terra
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| Banca de defesa: |
Martins, Felipe Terra,
Ellena, Javier Alcides,
Chagas, Rafael Pavão das |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal de Goiás
|
| Programa de Pós-Graduação: |
Programa de Pós-graduação em Química (IQ)
|
| Departamento: |
Instituto de Química - IQ (RG)
|
| País: |
Brasil
|
| Palavras-chave em Português: |
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| Área do conhecimento CNPq: |
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| Link de acesso: |
http://repositorio.bc.ufg.br/tede/handle/tede/3219
|
Resumo: |
Lamivudine and Efavirenz are anti-HIV drug largely used as, respectively a non-nucleoside and a nucleoside reverse transcriptase inhibitor as part of antiretroviral therapies. During the tests to obtain co-crystals of efavirenz with lamivudine it was obtained a novel crystalline phase, the polymorph of the hydrochloride salt of lamivudine. The structural and conformational analysis of this crystal modification showed that this keeps similarities, in intramolecular and intermolecular level, respectively with lamivudine hydrochloride and lamivudine hydrochloride monohydrate. Based on the intermolecular analysis and packing efficiency is expected that the polymorph of the hydrochloride salt of lamivudine is more soluble than the anhydrous phase. There are few reports on efavirenz solid state structures and behaviors. Crystal engineering strategies have not been well-exploited for this drug. In this sense, we delineate our synthesis strategy from the structural comparison and possibility of formation of intermolecular interactions patterns similar to those observed in the cocrystal of efavirenz and 4,4’-bipyridine. Two 4,4’-bipyridine-like compounds whose heterocycles are spaced by either an ethylene and an ethane moiety were cocrystallized together with efavirenz into solid state forms isostructural with respect to that of the drug cocrystal with 4,4’-bipyridine. The formation of a three-molecule entity based mainly on the hydrogen bonding donation from two efavirenz molecules to both pyridyl nitrogens of each coformer unit was kept in the three efavirenz cocrystals. The introduction of spacer groups in the coformers has altered the pattern of weak non-classical hydrogen bonds of the type C— H· · ·O. This intriduction was also related to the formation of a π-π stacking interaction between pyridyl rings of the ethane-spaced conformer. Furthermore, a polymorphic form of efavirenz with only one molecule in the asymmetric unit is reported for the first time here. This polymorph crystallizes in the monoclinic system and space group C2, strictly similar to form |
