Solid-state C NMR and molecular modeling studies of acetyl aleuritolic acid obtained from Croton cajucara Benth |
| |
Authors: | Rosane Aguiar da Silva San Gil, Magaly Gir o Albuquerque, Ricardo Bicca de Alencastro, Angelo da Cunha Pinto, Fabiano do Espí rito Santo Gomes, Tereza Neuma de Castro Dantas,Maria Aparecida Medeiros Maciel |
| |
Affiliation: | aDepartamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio de Janeiro, CT, Bloco A, Sala 616, 21941-972 Rio de Janeiro, RJ, Brazil;bDepartamento de Química, Universidade Federal do Rio Grande do Norte, Campus Universitário, 59078-970 Natal, RN, Brazil |
| |
Abstract: | Solid-state 13C nuclear magnetic resonance (13C NMR) with magic-angle spinning (MAS) and with cross-polarization and magic-angle spinning (CP/MAS) spectra, and differential scanning calorimetry (DSC) techniques were used to obtain structural data from a sample of acetyl aleuritolic acid (AAA) extracted from the stem bark of Croton cajucara Benth. (Euphorbiaceae) and recrystallized from acetone. Since solid-state 13C NMR results suggested the presence of more than one molecule in the unitary cell for the AAA, DSC analysis and molecular modeling calculations were used to access this possibility. The absence of phase transition peaks in the DSC spectra and the dimeric models of AAA simulated using the semi-empirical PM3 method are in agreement with that proposal. |
| |
Keywords: | Solid-state 13C NMR 13C NMR CP/MAS Acetyl aleuritolic acid Polymorphism Croton cajucara |
本文献已被 ScienceDirect 等数据库收录! |
|