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A one-pot synthesis of benzo[f]indole-4,9-diones from 1,4-naphthoquinone with α-aminoacetals has been developed. This method provides a straightforward synthesis of benzo[f]indole-4,9-diones via intramolecular nucleophilic attack of aminoquinones to aldehydes under mild reaction conditions. The detailed mechanism was also investigated.

A reductive C-1 acylation of 3,4-dihydroisoquinolines is developed that gives selective access to 1,1-disubstituted tetrahydroisoquinolines via a Ti(III)-catalyzed umpolung process.

Bi2O2Te is prepared by solid state reaction of a stoichiometric mixture of Bi, Bi2O3, and Te (evacuated silica tubes, 873 K, 10 h; complex heating schedule).

A Ti(III)-catalyzed intermolecular reductive coupling of ketones (I) and (IV) or imine (VI) with nitriles (II) is described, which gives direct access to α-hydroxylated and α-aminated ketones, respectively.

Reactions of bis(pentafluorophenyl)mercury with piperidine, sodium iso-propoxide or sodium tert-butoxide have yielded the corresponding 4-substituted tetrafluorophenylmercurials, [Hg(C6F4X-4)2] (X = cyclo-C5H10N (1), OCH(CH3)2 (2), OC(CH3)3 (3)), in reasonable yields but the bulkier nucleophiles, cis-2,6-dimethylpiperidine and 2,6-di-iso-propylphenolate (from sodium 2,6-di-iso-propylphenolate) decomposed the mercurial into pentafluorobenzene. Treatment of bis(pentafluorophenyl)mercury with another bulky nucleophile, 2,6-diphenylphenolate (from sodium 2,6-diphenylphenolate), in methanol, resulted in the unexpected formation of [Hg(C6F4(OMe)-4)2] (4). The structures of all the mercurials have linear C–Hg–C stereochemistry with two coplanar aryl rings. Amongst a complex series of supramolecular interactions, Hg⋯O bonding is observed for the alkoxy substituted mercurials but there are no Hg⋯N interactions in the structure of bis(2,3,5,6-tetrafluoro-4-piperidinophenyl)mercury.

From a series of 15 4-hydroxyprolinamides compounds (I) show promising activity as catalysts in the title reaction.

In the presence of CuSO4 and ascorbic acid terminal di-, tri-, tetra-, and pentaynes are found to undergo regioselective reaction with benzyl azide to afford 4-ethynyl-, 4-butadiynyl-, 4-hexatriynyl-, and 4-octatetraynyl-1,2,3-triazoles.

We have synthesized a tritiated form of 14α-hydroxy-β-cholest-7-ene-3,6-dione (5β-diketol) of high specific activity (1.74 TBq/mmol) from 7-dehydrocholesterol in seven steps with stereoselective introduction of the A/B cis ring junction as the key reaction. We have examined the ability of endocrine glands (prothoracic glands) of Locusta migratoria to use this molecule as a precursor of 3-dehydroecdysone and of ecdysone biosynthesis. A very efficient conversion of 5β-diketol to ecdysone and to 3-dehydroecdysone was monitored, which opens up new possibilities for the understanding of the role of 3-dehydro-compounds in ecdysteroid biosynthesis.

Two new benzimidazole derivatives were synthesized and evaluated for their ability to inhibit the binding at the strychnine-insensitive N -methyl- d -aspartate(NMDA)-linked glycine receptor. The most potent one, the 4,6-dichlorobenzimidazole-2-carboxylic acid 6 , was found to have submicromolar affinity for this receptor. The result of its functional test suggests that it acts as an antagonist of the NMDA receptor complex. Thus, this class of benzimidazole derivatives seems to constitute a group of potential antagonists for the strychnine-insensitive glycine receptor.

Starting from the two silylated cyanohydrins ( 2 and 5 ) we synthesized the four diastereomers of the title compound. This was achieved by adding either lithium trimethylsilylacetylide or the trimethylsilylacetylide magnesium bromide on the corresponding aldhehydes 3 and 6 , at −78°C. These compounds are to be tested as inhibitors of the ecdysone biosynthesis.

A convergent synthesis of 2′-O-methyl uridine (1) is described. The key steps in our synthesis are: (1) a facile obtention of the 2′-O-methyl sugar synthon using totally selective and efficient methylation conditions; (2) a stereoselective high-yield condensation with an uracil derivative, yielding the desired β-form.

In order to enhance the therapeutic efficacy of azido-thymidine (AZT) by improving its pharmacokinetic properties and to try to target its action to the lymphocytes, the phosphodiester of 3β(7β-hydroxycholesterol) and of 5′(3′deoxy, 3′azido-thymidine) 1 was synthesized using two different techniques of phosphorylation : the phosphoramidite and the hydrogen phosphonate methodologies. Preliminary results show an in vitro anti-HIV activity.

In order to enhance the antitumor efficacy of 7β-hydroxycholesterol by targetting its action to defined organs, the phosphoric acid esters of 3(7β-hydroxycholesteryl) and of 6(galactopyranosyl) 1 or 6(mannopyranosyl) 2 were synthesized by the phosphoramidite method (with protected C-1, 2, 3, 4 hydroxyl groups for the carbohydrates). As the protection of the sugars increased the length of the synthesis, we decided to use the hydrogen-phosphonate methodology which leads to a selective phosphorylation at the primary alcohol of carbohydrates and avoids the use of protected carbohydrates. Compound 2 was synthesized in good yield. However compound 1, probably due to steric hindrance, could not be obtained by this second method.

Several series of benzimidazole and imidazole derivatives have been synthesized and their biological activity evaluated. Their ability to inhibit human placental aromatase activity was tested in vitro. Ten of the tested compounds are more active towards aromatase than aminoglutethimide, the reference molecule. The most active compound XI is five times more potent in the same system. Compounds bearing an aryl group substituted by one or two halogen atom(s) (fluorine or chlorine) in position 4 or 2,4 respectively have also the most interesting activity.

The synthesis of 54 3-phenacyl-5-benzylidene-thiazolidine-2,4-diones is reported. Eight of them were tested for anti-oedema, analgesic and anticonvulsant activity. Only one compound showed significant anti-oedematous and analgesic activity. Three compounds protected against tonic seizures and death.

The four diastereomers 3 , elongated analogues of perhydroretinol, are synthesized starting from both optically pure 3-bromo-2-methyl-1-propanol enantiomers. All exhibit neurotrophic activity on cultured neuronal cells derived from fetal rat cerebral hemispheres.

In order to control the hydrogen embrittlement problems of steels, electrochemical hydrogen permeation experiments and hydrogen microprint technique were performed on nickel plated and electroless nickel (EN) plated steels to evaluate the beneficial effect of the impermeable coating. EN plating which had been annealed at 400 °C for 1 h led to a lowest hydrogen permeation rate and effective diffusivity due to its high hydrogen barrier efficiency. The effective diffusivity of the nickel plating and EN plating layers were calculated from permeation data of coated steels.

The preparation of five peracetylated a-glycosyl-H-phosphonates and their use in the straightforward preparation of phosphodiesters derivatives of 25-hydroxycholesterol is described. Examples of the extension of this process to other lipophilic alcohols are presented.

Synthesis and physico–chemical properties of new 3-benzyl-4-thioxo-5-arylideneimidazolidine-2-ones and 3-benzyl-5-arylideneimidazolidine-2,4-dione are described. These compounds were synthesized by condensation reaction from aromatic aldehydes and 3-substituted imidazolidine-2,4-diones or 4-thioxoimidazolidine-2-ones. The N -alkylation of 5-benzylideneimidazolidine-2,4-dione led simultaneously to mono- and dialkylated derivatives. The nucleophilic addition of 1-methyl-3-benzylimidazolidine-2,4-dione with 2-cyano-3-(3,4-dichlorophenyl) acrylate also yielded the 3-substituted 5-arylideneimidazolidine-2,4-dione derivative. Antimicrobial in vitro activity was determined on some compounds.

The aim of the present study was to describe the synthesis of a t rimethyl c yclohexenonic long chain f atty a lcohol ( t -CFA), and analyze its biological activity. Specifically, 3-(15-hydroxypentadecyl)-2,4,4-trimethyl-2-cyclohexen-1-one, the t -CFA containing 15 carbon atoms on the side chain ( t -CFA n =15) stimulated arginine vasopressin secretion in nerve terminals of the neurohypophysis. This effect was inhibited by extracellular calcium depletion, which suggets that t -CFA n =15 stimulates neuropeptide secretion through a calcium-dependent exocytosis mechanism.

Neurotrophic factors play an important role in the development and maintenance of neurons, thus providing a suitable therapeutic approach for the treatment of neurodegenerative diseases. However, their clinical use has revealed problematic because of a number of technical and biological disadvantages. Among the different strategies proposed to overcome such difficulties, the search for non-peptide substances with neurotrophic potential is giving promising results. Here we will expose major findings in this field, drawing special attention to cyclohexenonic long-chain fatty alcohols, a novel family of compounds that promote neuronal survival and neurite outgrowth.

The synthesis and physicochemical properties of 4-butyl-2H-benzo[1,4]thiazin-3-one derivatives are described. These new compounds were synthesised by alkylation in 4-N position and acylation and/or alkylation of 6-NH2 by phase transfer catalysis. Acid hydrolysis of 6-alkylacylamino group yielded 6-alkylamino-4-butyl-2H-benzo[1,4]thiazin-3-ones. The antimicrobial in vitro activity was determined on five compounds.

Fractionation of stem barks of Terminalia superba yielded two new ellagic acid derivatives, 3,4'-di-O-methylellagic acid 3'-O-beta-D-xylopyranoside (1) and 4'-O-galloy-3,3'-di-O-methylellagic acid 4-O-beta-D-xylopyranoside (2) together with known 3,3'-di-O-methylellagic acid, ellagic acid and 3,3'-di-O-methylellagic acid 4'-O-beta-D-xylopyranoside. Compounds (1) and (2) showed significant alpha-glucosidase inhibition activity and possessed significant immunoinhibitory activities with no cytotoxic effects.

The solvent-free potassium permanganate (KMnO4)–promoted oxidation of alcohols into the corresponding carbonyl derivatives has been examined in detail with respect to the importance of supporting materials and supporting irradiation. Secondary alcohols are oxidized very efficiently to the corresponding ketones at ambient temperature by KMnO4 absorbed on a fourfold molar amount of copper(II) sulfate pentahydrate. The reaction is accelerated considerably by ultrasonic irradiation and drastically by microwave irradiation. Under the latter conditions, also hydroquinone can be converted 100% into p-benzoquinone within 4.5 min. Benzylic alcohols are oxidized most efficiently to the corresponding benzaldehydes under heterogeneous reaction conditions.