Flavonoids from Friesodielsia discolor

Phytochemical investigation of the fresh leaves of Friesodielsia discolor (Craib) D. Das led to the isolation of four new flavonoids, 3′-formyl-2′,4′-dihydroxy-6′-methoxychalcone (1), 8-formyl-7-hydroxy-5-methoxyflavanone (2), 8-formyl-5,7-dihydroxyflavanone (3) and 5,3′-dihydroxy-7-methoxyflavone (6), together with two known compounds, lawinal (4) and tectochrysin (5). The structures of the compounds were elucidated by spectroscopic analysis, mainly 1D and 2D NMR techniques (¹H, ¹³C, COSY, HMQC and HMBC), as well as comparison with literature data. The isolates were tested for antiplasmodial, antimycobacterial and cytotoxic activities. Compounds 1, 2, 5 and 6 exhibited cytotoxicity against human tumor cell lines, KB and MCF-7 with the IC₅₀ values in the range of 3.45–14.82 μg/ml. Compounds 1, 2, and 5 also showed significant antiplasmodial activity with respective IC₅₀ values of 2.75, 2.78 and 2.08 μg/ml.     

Bioactive styryllactones,two new naphthoquinones and one new styryllactone,and other constituents from Goniothalamus scortechinii

Two new naphthoquinones, goniothalaminone A (1) and B (2), and a new styryllactone, (?)-8-epi-9-deoxygoniopypyrone acetate (12) together with one known naphthoquinone (3), one known indolequinone (4), one known 1-azaanthraquinone (5), six known styryllactones (6–11) and one known sesquiterpene (13) were isolated from the roots and leaves of Goniothalamus scortechinii. The structures of the new compounds were elucidated by spectroscopic analysis and of the known compounds by comparison of their physical, UV, IR, ¹H and ¹³C NMR data with those of published compounds. Antiplasmodial, antimycobacterial and cytotoxic activities of the styryllactones were evaluated. Compounds 6–10 exhibited cytotoxic against human cancer cell lines, KB, BC and NCI-H187 with IC₅₀ values ranging from 0.13 to 11.7 μg/ml.