New 3- and 4-hydroxyfuranones as anti-oxidants and anti-inflammatory agents.

Two series of new furanones substituted by methylsulfonylphenyl or methylsulfamidophenyl moieties were found to protect against oxidation damage by inhibiting or quenching free radicals and reactive oxygen species in in vitro experiments. The effect on lipid peroxidation was also examined. In addition, we investigated the activity of products in two models of inflammation: phorbol ester-induced ear edema in mice and carrageenan-induced paw edema in rat.

Novel 4,5-diaryl-3-hydroxy-2(5H)-furanones as anti-oxidants and anti-inflammatory agents.

In order to study the effect of phenol moieties on biological activities of ascorbic acid derivatives, we synthesized 13 novel 4,5-diaryl-3-hydroxy-2(5H)-furanones 5a-m with various substitution patterns. Compound 5 g bearing a 2,3-dihydroxy phenyl ring on the 5-position of the heterocycle appeared to be the most powerful anti-oxidant furanone with reducing activity against DPPH (IC(50)=10.3 microM), superoxide anion quenching capacity (IC(50)=0.

Synthesis of N-substituted 4,6-dioxo-imidazo[3,4-c] thiazoles and their analgesic activity in mice.

A new series of N-substituted dioxo-imidazo[3,4-c]thiazoles have been prepared and evaluated for their analgesic activity. The structures of these new derivatives were confirmed by lR, 1H NMR and 13C NMR spectra, and by elemental analysis. When administered intraperitoneally to mice all derivatives were devoid of any toxic effect, even at the high dose of 800 mg kg(-1).

[Synthesis and antidepressive activity study of aryl and heteroaryl carboxamides of benzylpiperazine].

The synthesis of 44 original amide derivatives of benzylpiperazine and some analogues of befuraline and piberaline is reported. All compounds have been tested as antidepressive agents. According to the tests, amides 1, 24 and mainly 31 (dihydrobefuraline) seem to provide elevated antidepressive activity.

Antioxidant properties of novel lipophilic ascorbic acid analogues.

Structural modifications of ascorbic acid by the introduction of lipophilic moieties has led to derivatives with increased stability against thermal and oxidative degradation. Two series of new lipophilic ascorbic analogues were synthesized to obtain antioxidants devoid of autooxidant properties: 4-benzoyl-3-hydroxyfuran-2(5H)-ones (3a-j) and 4-acetyl-5-aryl-3,4-dihydrofuran-2(5H)ones (5a-f). These compounds were submitted to three different tests: reduction of the stable free radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH); superoxide-anion scavenging assay; and lipid-peroxidation assay.