New flavanone and other constituents from erythrina senegalensis A. DC. (fabaceae).

The chemical investigation of the methanol trunk bark extract of Erythrina senegalensis led to the isolation of a new flavanone, 5,7,4'-trihydroxy-3',5'-bis(3-methylbutadienyl)flavanone (trivially named senegalensisnone) ( 1 ), together with seven known compounds, abyssinone-V-4'- O -methyl ether ( 2 ), abyssinone V ( 3 ), Calopocarpin ( 4 ), genistein (5 ) mixture of stigmasterol ( 6 ) and β -sitosterol ( 7 ) and β -sitosterol-3- O - β -D-glucopyranoside ( 8 ). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. The absolute configuration of 1 was deduced based on comparison of its experimental CD with that of similar compound. All the compounds were tested for their antibacterial, antifungal and antioxidant activities. Compound 4 displayed weak antibacterial activity against Salmonella enteritidis with MIC value of 62.5  μ g/mL. All the isolates were found to be inactive as antioxidant agents in the DPPH, ABTS and FRAP assays.