Cytotoxic and Antimicrobial Benzophenones from the Leaves of Tovomita longifolia

Abstract

Bioassay-guided fractionation of the chloroform and ethanol extracts of Tovomita longifolia leaves using cytotoxic and antimicrobial assays resulted in the isolation of four new benzophenones, (E)-3-(2-hydroxy-7-methyl-3-methyleneoct-6-enyl)-2,4,6-trihydroxybenzophenone (1), (E)-3-(6-hydroxy-3,7-dimethylocta-2,7-dienyl)-2,4,6-trihydroxybenzophenone (2), 8-benzoyl-2-(4-methylpenten-3-yl)chromane-3,5,7-triol (3), and 5-benzoyl-1,1,4a-trimethyl-2,3,4,4a,9,9a-hexahydro-1H-xanthene-6,8-diol (4), and two known benzophenones, 4-geranyloxy-2,6-dihydroxybenzophenone (5) and 3-geranyl-2,4,6-trihydroxybenzophenone (6). The structures of 1-4 were established by spectroscopic means and by molecular modeling calculations. Compounds 1 and 3-5 demonstrated cytotoxic activities against breast (MCF-7), central nervous system (SF-268), and lung (H-460) human cancer cell lines, while compounds 3-6 showed antimicrobial activity against Klebsiella pneumoniae, Mycobacterium smegmatis, Pseudomonas aeruginosa, Salmonella gallinarum, and Staphylococcus aureus.

Plant use in the medicinal practices known as “strict diets” in Chazuta valley (Peruvian Amazon)

“…Several compounds isolated from Tovomita species have demonstrated antimicrobial activity, such as xanthones, benzophenones and betulinic acid (Pecchio et al, 2006;Zhang et al, 2002).…”

“…Also, natural occurring benzophenones, and isoprenylated benzophenones isolated from Clusia species in particular, have proven antimicrobial activity (Finnegan et al, 1973;Pecchio et al, 2006;Schultz et al, 2002).…”

Vochysiaceae: secondary metabolites, ethnopharmacology and pharmacological potential

“…Besides those compounds there is no correlation on the literature, associating this classe of metabolites with the reported pharmacological effects. (Pecchio et al 2006). Structure 87 was reported from barks of V. tyrsoidea (Corrêa et al 1975).…”

Synthesis of benzophenones from geminal biaryl ethenes using m-chloroperbenzoic acid

“…11 Recently, several naturally occurring prenylated and isoprenylated benzophenones have been identified as potent cytotoxic and antimicrobial agents. 12 In addition, some synthetic benzophenones have been reported as a new class of non-nucleoside HIV reverse transcriptase inhibitors. 13 While the chemistry of symmetrical and unsymmetrical benzophenones includes many synthetic methods, most of them fall into the categories of the oxidation of secondary alcohols in the presence of organometallic complexes, such as ruthenium(III) meso-tetraphenylporphyrin chloride, 14 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)/I 2 O 5 , 15 oxone, 16 palladium salts, 17 iron(III) nitrate, 18 Ag/HT, 19 and cuprous chloride.…”