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Xanthones or xanthen-9H-ones (dibenzo-gamma-pirone) comprise an important class of oxygenated heterocycles whose role is well-known in Medicinal Chemistry. The biological activities of this class of compounds are associated with their tricyclic scaffold but vary depending on the nature and/or position of the different substituents. In this review, an array(More)
Many tumor cells become resistant to commonly used cytotoxic drugs due to the overexpression of ATP-binding cassette (ABC) transporters, namely P-glycoprotein (P-gp). The discovery of the reversal of multidrug resistance (MDR) by verapamil occured in 1981, and in 1968 MDR Chinese hamster cell lines were isolated for the first time. Since then, P-gp(More)
PURPOSE Synthesize and evaluate the protective activity against tertbutylhydroperoxide-induced toxicity in freshly isolated rat hepatocytes of trans-kielcorin, trans-isokielcorin B, as well as their respective building blocks 3,4-dihydroxy-2-methoxyxanthone and 2,3-dihydroxy-4-methoxyxanthone. METHODS Wistar rats, weighing 200-250g were used. Hepatocyte(More)
The interest in the synthesis and applications of thioxanthones, dibenzo-gamma-thiopyrones, started in the beginning of the 20th century. Thioxanthones are traditionally synthesized via benzophenone, diarylthioether or diarylthioester intermediates. In recent years, more efficient and cleaner synthetic methodologies are being applied to obtain thioxanthone(More)
Further study of one of the fractions from the wood of Artocarpus elasticus furnished two new prenylated flavonoids artelastocarpin and carpelastofuran as well as ethyl 2,4-dihydroxybenzoate. The two flavonoids and the prenylated flavonoids artelastin, artelastochromene, artelasticin, artocarpesin, and cyclocommunin isolated earlier from this species were(More)
Further study of the wood of Calophyllum teysmannii Miq. var. inophylloide from Thailand yielded the xanthones 1,2,8-trimethoxyxanthone, 6-hydroxy-1,2,5,7-tetramethoxyxanthone and 3-(3'-carboxybutyl)-4-methoxyxanthone (teysmannic acid) in addition to scriblitifolic acid, 1,7-dihydroxyxanthone and the benzoic acid derivative leiocarpic acid.
Catechols from abietic acid were prepared by a short and good yielding chemical process and further evaluated for several biological activities namely, antifungal, antitumoral, antimutagenic, antiviral, antiproliferative and inhibition of nitric oxide. Their properties were compared with those of carnosic acid (6), a naturally occurring catechol with an(More)
Extraction of the stem bark of KNEMA LAURINA Warb. and KNEMA TENUINERVIA W. J. J. O. de Wilde ssp. SETOSA de Wilde furnished 3-(12-phenyl-8 Z-dodecenyl)-phenol and 3-(8 Z-pentadecenyl)-phenol together with 8-hydroxy-6-methoxy-3- N-pentylisocoumarin, respectively. 2-Carboxy-3-(12-phenyldodecyl)-phenol) and 2,4-dihydroxy-6-(10-phenyldecyl)-acetophenone were(More)
Five known abietane diterpenes of the royleanone and coleon type, namely, fatty acid esters of 7alpha-acyloxy-6beta-hydroxyroyleanone (1), grandidone A (2), 7alpha-acetoxy-6beta-hydroxyroyleanone (3), 6beta,7alpha-dihydroxyroyleanone (4) and coleon U (5), isolated from Plectranthus grandidentatus, were evaluated for their effect on the proliferation of(More)
Among the known synthetic routes to obtain xanthones, the Grover, Shah, and Shah reaction, the cyclodehydration of 2, 2'-dihydroxybenzophenones and electrophilic cycloacylation of 2-aryloxybenzoic acids are the most popular methods. Due to important biological applications of xanthones, some synthetic strategies leading to more complex derivatives have been(More)