Espectrometria de Massas de Diterpenos do Tipo Clerodano Isolados de Croton cajucara

Abstract

Neste trabalho utilizou-se espectrometria de massas objetivando-se a identificação de fragmentos característicos de diterpenos do tipo clerodano contendo carbonila α,β-insaturada no anel A do sistema decalínico. Para tanto, dados de espectrometria de massas foram analisados para os seguintes 19-nor-clerodanos de sistemas enona: trans-desidrocrotonina (1), trans-crotonina (2), cis-cajucarina B (3), trans-cajucarina B (4) e cajucarinolida (5) e para os clerodanos isosacacarina (6) e cajucarina A (7), isolados das cascas do caule de Croton cajucara Benth, bem como para clerodanos de sistemas enona isolados de outras espécies. A junção trans de clerodanos foi claramente correlacionada com a presença dos íons característico de m/z 95, 121 e 205; os sistemas de junção cis apresentaram íons característicos de m/z 122 e 124. A junção trans de 19-nor-clerodano foi correlacionada com a presença dos íons característico de m/z 161, 134 e 121.

Synthesis, NMR data and theoretical study of semi-synthetic derivatives from trans-dehydrocrotonin

“…Comparatively, it was observed at Mass spectrometry data also provided valuable information for structural characterization and confirmation of t-CTN derivative, which presented molecular ion peak with m/z ratio 316, corresponding to the molecular mass of t-CTN. Additionally, it was observed typical fragments already described for clerodanes skeleton [25], such as base peak with m/z ratio 94.…”

“…It was found the molecular ion peak with m/z ratio 318, which is the exactly molecular mass for both t-CTN-a-OL and t-CTN-b-OL. Moreover, typical fragments already described for clerodane skeleton [25], such as base peak with m/z ratio 95 for t-CTN-b-OL and m/z ratio 161 for t-CTN-a-OL were also presented in mass spectra data.…”