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Diclavatol and tetronic acids from Penicillium griseoroseum
José Vinicius da Silva1, Taicia Pacheco Fill, Bianca Ferreira da Silva
1Departamento de Química, Universidade Federal de São Carlos, CEP 13.565-905, CP 676, São Carlos, SP, Brazil.
Abstract:
In our continuous studies on the chemistry of the endophytic fungus Penicillium griseoroseum, an endophyte isolated from fruits of Coffea arabica, we isolated clavatol, a dimethylated tetraketide, and its dimer which appears to be a novel natural compound. The studies also resulted in the identification of two known tetronic acids, viridicatic acid and terrestric acid, found in ethyl acetate and n-butanol extracts. Spectroscopic studies using 1-D and 2-D NMR and MS/MS analysis were performed to determine the structures of these compounds, first reported by this Penicillium. Two other tetronic acids congeners were identified through HPLC/MS/MS studies, based on fragmentation pattern of ions produced from ionised tetronic acids, and UV light absorptions.
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