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Phytotoxic Compounds from the New Coprophilous Fungus Guanomyces polythrix

“…Compounds 1 − 5 are new natural products and were characterized by spectroscopic and chiroptical methods as (2 S ,3 S )-5-hydroxy-6,8-dimethoxy-2,3-dimethyl-4 H -2,3-dihydronaphtho[2,3- b ]-pyran-4-one ( 1 ); (2 S ,3 S )-5-hydroxy-6,8,10-trimethoxy-2,3-dimethyl-4 H -2,3-dihydronaphtho[2,3- b ]-pyran-4-one ( 2 ); (2 S )-5-hydroxy-6,8-dimethoxy-2-methyl-4 H -2,3-dihydronaphtho[2,3- b ]-pyran-4-one ( 3 ); (2 S )-5-hydroxy-6,8,10-trimethoxy-2-methyl-4 H -2,3-dihydronaphtho[2,3- b ]-pyran-4-one ( 4 ); and 5-hydroxy-6,8-dimethoxy-2,3-dimethyl-4 H -naphtho[2,3- b ]-pyran-4-one ( 5 ). In addition, the known compounds rubrofusarin B ( 6 ), − emodin ( 7 ), , citrinin ( 8 ), , and 4-hydroxybenzoic acid methyl ester ( 9 ) were obtained. The spectral properties of the known compounds, including IR, 1 H NMR, and 13 C NMR data, were identical to those previously described in the literature.…”

Total Synthesis of Heliannone A and (R,S)-Heliannone B, Two Bioactive Flavonoids from Helianthus annuus Cultivars

“…Then 2 drops of concentrated HCl was added, and the solution was refluxed for 45 min to decompose excess Ac 2 O. The reaction mixture on concentration under reduced pressure yielded a yellow solid, which on crystallization from hexane−EtOAc gave 5 as a yellow crystalline solid (3.1 g, 92%), mp 169−172 °C (lit . mp 173 °C).…”

Constituents from the Stem Wood of Euphorbia quinquecostata with Phorbol Dibutyrate Receptor-Binding Inhibitory Activity

“…Lupeol acetate : white crystals (CHCl 3 ): mp 210−212 °C; [α] 20 D +20° ( c 0.5 CHCl 3 ), lit . mp 215−216 °C; [α] 30 D +46° ( c 1.5 CHCl 3 ), which exhibited comparable spectral (UV, IR, 1 H NMR, 13 C NMR, EIMS) data to published values. , …”