Publications by authors named "Maria Amelia D Boaventura"

Thirteen natural products derivatives of hydroxyl amide class, three described for the first time, were synthesized by reaction of three indole acids and 3,4,5-trimethoxybenzoic acid with six different amino alcohols in the presence of triphenylphosphine and N-bromosuccinimide. The derivatives were tested against the Gram (+) bacteria Staphylococcus aureus and Bacillus cereus, Gram (-) Pseudomonas aeruginosa and Escherichia coli, besides the yeast Candida albicans. One of the compounds (7) was selectively active against C.

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Auxins, such as indole-3-acetic acid (IAA), are important in plant germination and growth, while physiological polyamines, such as putrescine, are involved in cell proliferation and differentiation, and their concentrations increase during germination. In this work, novel indole amides were synthesized in good yields by monoacylation of morpholine and unprotected symmetrical diamines with indole-3-carboxylic acid, a putative metabolite of IAA, possessing no auxin-like activity. These amides were tested for their effects on seed germination and growth of the radicles and shoots of Lactuca sativa (lettuce) and Allium cepa (onion) seedlings, at 100.

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A highly rearranged novel dilactone was the single product isolated from Baeyer-Villiger oxidation of a norketone prepared from grandiflorenic acid, a natural kaurane diterpene. The complete 1H and 13C NMR assignment is presented for this novel compound that showed discrete in vitro antibacterial activity.

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Sixteen extracts, obtained from eight Brazilian plants of Annonaceae family, were screened for their antibacterial activity: Xylopia frutescens, X. aromatica, X. amazonica, X.

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Kaurenoic and grandiflorenic acid, isolated from Wedelia paludosa (Asteraceae), some derivatives from these acids (alcohols, esters, amides, lactones, oximes) and other naturally occurring kaurane diterpenes were tested for their action on the growth of radical and shoot of Lactuca sativa. Gibberellic acid, GA3, a commercially available phytohormone, belonging to the same class of diterpenes, was also tested. Some of the tested substances showed a remarkable activity either in the inhibition or in stimulation of L.

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In the search for new routes in the synthesis of hydroxylated kaurane diterpenoids, Verticillium lecanii, grown in a mineral liquid medium for 48 h, was fed with ent-17,19-dihydroxy-16betaH-kaurane, obtained by hydroboration/oxidation of kaurenoic acid, a natural product easily isolated from plants of the genera Xylopia (Annonaceae) and Wedelia (Asteraceae). After 14 days, the culture medium was extracted with ethyl acetate, and the metabolites were purified by column chromatography on silica gel. The results show that V.

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