Solid-state compounds of 4-methoxybenzylidenepyruvate and cinnamylidenepyruvates with thorium (IV) - Preparation and thermal studies

By close control of experimental variables affecting precipitation, solid-state compounds of the type Th(OH)(m)L4-m.nH(2)O, where L stands for 4-methoxy-benzylidenepyruvate, cinnamylidenepyruvate or 4-dimethylaminocinnamylidene-pyruvate; m=0 to 3 and n=0.5-3 were isolated. Chemical analysis, TG, DTG, DSC and X-ray powder diffractometry have been employed to characterize and to study the thermal behavior of these compounds in dynamic air atmosphere. In all cases, hydration water is slowly lost between 30 and 160degreesC; a continuous, slow rate, mass loss is observed thereafter and beyond 280-400degreesC the rate of decomposition/oxidation increased rapidly, to give ThO2 as the final product, beginning at 412-510degreesC. The results associated with the hydroxo-compounds indicate that the loss of constitution water (OH ions) and the decomposition / oxidation of the organic moieties occur as simultaneous process.

Effect of non-steroidal anti-inflammatory drugs (NSAID) on the histamine release induced by compound 48/80 and cardiac anaphylaxis in guinea-pig isolated heart

Histamine release from guinea pig heart treated with compound 48/80 was potentiated by the cyclooxygenase inhibitors indomethacin and piroxicam but not by aspirin or phenylbutazone. This differential effect suggests that the potentiation is not merely due to an inhibition of prostaglandin synthesis. Piroxicam potentiated the histamine release induced by cardiac anaphylaxis whereas indomethacin reduced this effect. The SRS-A antagonist FPL 55712 inhibited histamine release induced by cardiac anaphylaxis, but not that evoked by compound 48/80, and also prevented the potentiation due to indomethacin and piroxicam. In total, these data suggest that the potentiation of histamine release by piroxicam and indomethacin is probably due to a diversion of arachidonic acid metabolism from the cyclooxygenase to the lipoxygenase pathways. The resulting lipoxygenase products may then regulate histamine release, with the secretion due to antigen being more sensitive to such modulation than that evoked by compound 48/80.

Evaluating methods for the isolation of marine-derived fungal strains and production of bioactive secondary metabolites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Neolignans, styrylpyrones and flavonoids from an Aniba species

The trunk wood and barks from an Aniba species contain four esters of benzoic acid with cinnamyl alcohol, five benzofuran neolignans, licarin-A, burchellin, cis-burchellin, burchellin-rearranged and cis-burchellin-rearranged, one tetrahydrofuran neolignan, aristolignin, three bicyclooctane guianin-type neolignans, (7S, 8S, 1'R, 5'R)-4-hydroxy-3,3'-dimethoxy-4',6'-dioxo-8.1', 7.5'-neolignan-Delta: 1,3,5,2',8' and the new (7S, 8S, 1'R, 4'R, 5'S)-4'-hydroxy-3,4,3'-trimethoxy-6'-oxo-8.1', 7.5'-neolignan-Delta: 1,3,5,2',8' and (7S, 8S, 1'R, 4'R, 5'S)-4,4'-dihydroxy-3,3'-dimethoxy-6'-oxo-8.1', 7.5'-neolignan-Delta: 1,3,5,2',8', one new bicyclooctane canellin-type neolignan (7S, 8S, 1'S, 4'R, 5'R, 6'S)-4',6'-dihydroxy-3,4-dimethoxy-3'-oxo-8.1', 7.5'-neolignan-Delta: 1,3,5,8', two styrylpyrones, 4-methoxy-6-(11,12-dimethoxy-trans-styryl)-2-pyrone and 6-(11,12-methylenedioxy-trans-styryl)-4-methoxy-2-pyrone, two styrylpyrone dimers: 4'-methoxy-8-(11,12-dimethoxyphenyl)-7-[6-(4-methoxy-2-pyronyl)-6-(E)-styryl-1'-oxabicyclo[4,2,0]octa-4'-en-2'-one and the new 11,12-dimethoxyphenyl-7,7'-di-[6-(4-methoxy-2-pyronyl)]-cyclobutane and six flavonoids, 3,5-dihydroxy-7,4'-dimethoxyflavone, 5-hydroxy-3,7,4'-trimethoxyflavone, 3,5,4'-trihydroxy-7-methoxyflavone, 2,3-dihydro-5-hydroxy-7,4'-dimethoxyflavone, 2,3-dihydro-3,5-dihydroxy-7-methoxyflavone, 2,3-dihydro-3,5-dihydroxy-7,4'-dimethoxyflavone and a new flavan, 6,7,3',4',5'-pentamethoxyflavan. (C) 1997 Elsevier B.V. Ltd.

A new imidazole alkaloid and other constituents from Pilocarpus grandiflorus and their antifungal activity

The stems of Pilocarpus grandiflorus have afforded the new imidazole alkaloid 4,6-dehydro-1,2,4,5-tetrahydro-2,5-dioxopilocarpine in addition to the 17 known compounds germanicol, β-amiryn, ocotillone, stigmast-4-en-3-one, 3β-hydroxy-stigmast-5-en-7-one, 6β-hydroxy-stigmast-4-en-3-one, β-sitosterol, scopoletin, 3-(1′,1′-dimethylallyl)-scopoletin, elisin, dictamine, 4-methoxy-2-quinolone, platydesmine, syringaresinol, syringaldehyde, syringic acid and vanillic acid. Their structures were elucidated on the basis of chemical and spectroscopic evidence. The phenolic compounds vanillic acid and syringaldehyde and the furoquinoline alkaloid platydesmine exhibited antifungal activity against Leucoagaricus gongylophorus, the symbiotic fungus of leaf-cutting ants (Atta sexdens rubropilosa). © 2005 Verlag der Zeitschrift für Naturforschung.

Intraspecific variability of dihydrochalcone, chromenes and benzoic acid derivatives in leaves of Piper aduncum L. (Piperaceae)

Chemical analysis carried out in leaves of 18 specimens of Piper aduncum L. (Piperaceae) occurring at Ripasa Reserve, Araraquara, SP, Brazil indicated two distinct populations when investigated over a period of 14 months (January 2000 to February 2001) and then submitted to cluster analysis. The two groups were characterized by accumulation of prenylated benzoic acids, chromenes and dihydrochalcone, respectively. A total of seven compounds were identified by HPLC analysis and compared with standards including two prenylated benzoic acid [aduncumene (1) and 3-(3′-7′-dimethyl-2′-6′-octadienyl)- 4-methoxy-benzoic acid (5)], four chromenes [methyl 2,2-dimethyl-8-(3′- methyl-2′-butenyl)-2H-1-chromene-6-carboxylate (4), methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (2b), methyl 8-hydroxy-2,2-dimethyl-2H- 1-chromene-6-carboxylate (3) and 2,2-dimethyl-2H-1-chromene-6-carboxylic acid (2a)] and one dihydrochalcone [2′,6′-dihydroxy-4′-methoxy- dihydrochalcone (6)]. © 2009 Academic Journals.

Lichen metabolites modulate hydrogen peroxide and nitric oxide in mouse macrophages

The activities of perlatolic acid (1), atranorin (2), and lecanoric acid (3) and their derivatives, such as orsellinates and β-methyl orsellinates obtained by alcoholysis, were assessed for stimulation of the release of hydrogen peroxide and nitric oxide in cultures of peritoneal macrophage cells from mice. The hydrogen peroxide production was estimated by oxidation of phenol red, while the Griess reagent was used to determine the nitric oxide production. 1 and 4-methoxy-ethyl orsellinate (XVII) were the compounds that induced the greatest release of H 2O 2, whereas n-pentyl orsellinate (IV), iso-propyl orsellinate (V), sec-butyl orsellinate (VI), and XVII induced a small release of NO. These results indicate that lichen products and their derivatives have potential immune-modulating activities. © 2009 Verlag der Zeitschrift für Naturforschung, Tübingen.

Mast cells modulate the inflammatory process in endotoxin-induced uveitis

Purpose: To investigate the role of mast cells and annexin-A1 (Anxa1) in endotoxin-induced uveitis (EIU). Methods: EIU was induced by injection of lipopolysaccharide (LPS) into the paws of rats, which were then sacrificed after 24 and 48 h. To assess EIU in the absence of mast cells, groups of animals were pretreated with compound 48/80 (c48/80) and sacrificed after 24 h after no treatment or EIU induction. The eyes were used for histological studies and the aqueous humor (AqH) pool was used for the analysis of transmigrated cells and Anxa1 levels. In inflammatory cells, Anxa1 expression was monitored by immunohistochemistry. Results: After 24 h, rats with EIU exhibited degranulated mast cells, associated with elevated numbers of infiltrating leukocytes and the high expression of Anxa1 in the AqH and the neutrophils. After 48 h of EIU, the mast cells were intact, indicating granule re-synthesis, and there was a reduction of neutrophil transmigration and an increase in the number of mononuclear phagocytic cells in ocular tissues. Anxa1 expression was decreased in neutrophils but increased in mononuclear phagocytic cells. In the animals pretreated with c48/80 and subjected to EIU, mast cells responded to this secretagogue by degranulating and few transmigrated neutrophils were observed. Conclustions: We report that mast cells are a potential source of pharmacological mediators that are strongly linked to the pathophysiology of EIU, and the endogenous protein Anxa1 is a mediator in the homeostasis of the inflammatory process with anti-migratory effects on leukocytes, which supports further studies of this protein as an innovative therapy for uveitis. © 2011 Molecular Vision.

Utilização da técnica hifenada CLAE-DAD-IES-EM na detecção e caracterização de substâncias em Ocotea paranapiacabensis e Aniba firmula (Lauraceae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo de aspectos químicos, biológicos e biossintéticos em Piper fuligineum Kunth(Piperaceae)

Pós-graduação em Química - IQ

Estudo químico e avaliação da atividade biológica de Eugenia brasiliensis e Eugenia involucrata (Myrtaceae)

Pós-graduação em Química - IQ

Anti-Helicobacter pylori activity and oxidative burst inhibition by the naphthoquinone 5-methoxy-3,4-dehydroxanthomegnin from Paepalanthus latipes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)