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An efficient copper-catalyzed multicomponent reaction was developed for the synthesis of (arylselanyl)- or (arylsulfenyl)-alkyl-1,2,3-triazolo-1,3,6-triazonines. The products were obtained in moderate to excellent yields via the reaction of o-phenylenediamine, 2-azidobenzaldehyde and different arylchalcogenyl alkynes using catalytic copper iodide in 1,4-dioxane at 100 °C. The reactions tolerated a range of substituents on the arylchalcogenyl alkynes and proved to be an efficient methodology for the combinatorial synthesis of new selenium or sulfur-containing triazonine derivatives.

A convenient synthesis of 1-(2-organylchalcogenylethynyl)-2-butylselenanylbenzenes was established taking advantage of the selective reaction of 1-(2,2-dibromovinyl)-2-butylselenanylbenzenes with thiols or diorganyl diselenides. The new 1-(2-chalcogenylethynyl)-2-butylselenanylbenzenes were prepared in good yields and used as precursors of 2-organylchalcogenylbenzo[b]selenophenes via electrophilic cyclization using I2, Br2 or PhSeBr as electrophiles. Different classes of new 3-substituted- (3-iodo, 3-bromo, 3-phenylselenanyl) benzo[b]selenophenes were prepared in good yields. The synthetic application of the obtained products was demonstrated employing the benzo[b]selenophenes in Suzuki and Sonogashira cross-coupling reactions.

The use of sonochemistry is described in the organocatalytic enamine–azide [3 + 2] cycloaddition between 1,3-diketones and aryl azidophenyl selenides. These sonochemically promoted reactions were found to be amenable to a range of 1,3-diketones or aryl azidophenyl selenides, providing an efficient access to new ((arylselanyl)phenyl-1H-1,2,3-triazol-4-yl)ketones in good to excellent yields and short reaction times. In addition, this protocol was extended to β-keto esters, β-keto amides and α-cyano ketones. Selanyltriazoyl carboxylates, carboxamides and carbonitriles were synthesized in high yields at short times of reaction under very mild reaction conditions.

A significant number of important acyl-transfer reactions, such as direct acylation, ortho acylation, heteroatom acylation, and a diversity of cyclization reactions using the title compound as a key starting material, have been described in recent years. Just like a sleeping beauty, α-oxocarboxylic acids were awakened from a 17-year sleep to become important reagents in classical and new acylation reactions. The greener characteristic of the coproduct formed in reactions using α-keto acid (only CO2), together with its versatility as a building block in catalytic organic synthesis, accredit it as a candidate to green acylating agent, an alternative to acyl chloride, and other acyl-transfer reagents. This review presents the impressive breakthroughs achieved mainly in the past decade in the development of new catalytic reactions for the formation of C–C, C–N, and C–S bonds using α-keto acids.

We described herein the use of sonochemistry in the organocatalytic enamine-azide [3+2] cycloadditions of β-oxo-amides with a range of substituted aryl azides. These sonochemical promoted reactions were found to be amenable to a range of β-oxo amides or aryl azides, providing an efficient access to new N-aryl-1,2,3-triazoyl carboxamides in good to excellent yields and short times of reaction.

The use of renewable feedstocks, which may substitute those derived from petroleum, is currently a great challenge in the chemical and pharmaceutical industries. However, plant essential oils (EOs) that have been studied for their biological activities, such as antioxidant, antimicrobial, antifungal and antinociceptive are generally regarded as safe additives maintaining the microbiological stability of foods. EOs are a mixture of natural volatile compounds, that are predominantly formed during the secondary metabolism in plants and commonly concentrated in the leaves, bark or fruits of aromatic plants. They are complex mixtures composed mainly of terpenes (hydrocarbons or oxygenated compounds) and phenylpropanoids, which can be used as a source of raw materials for fine chemicals industry. In recent years, researchers and industries have been focusing on the major compounds of EOs in order to use them as solvents or as bio-based building blocks adding value to this material derived from biomass.

We present here the synthesis of novel (Z)-2-organylselanyl ketoximes by nucleophilic substitution reaction of E/Z mixtures of 2-bromo ketoximes with nucleophilic species of selenium, which were generated in situ by simple cleavage of diorganyl diselenides with NaBH4 using ethanol/THF as solvent. The new 2-organylselanyl ketoximes were synthesized in moderate to good yields and with selectivity for the (Z)-configuration. The synthesized (Z)-2-arylselanylacetophenone oximes were submitted to the Beckmann rearrangement, furnishing the corresponding N-aryl-2-(selanyl)acetamides. (Z)-1-Phenyl-2-(phenylselanyl) ketoxime has antifungal activity against Sphaceloma ampelinum and a good level of antioxidant activity in vitro in DPPH, ABTS, FRAP and lipid peroxidation assays.

We describe a selective method for synthesis of 4-chalcogenylmethyl-1,3-dioxolan-2-ones and 1,3-bis(organylchalcogenyl)propan-2-ols in a short reaction time through stoichiometric control. The use of 3-O-tosyl glycerol 1,2-carbonate and a set of aryl and alkyl diorganyl dichalcogenides afforded the desired products in good to excellent yields. We also describe a synthetic application to 4-chalcogenylmethyl-1,3-dioxolan-2-ones by base promoted the synthesis of 3-(arylchalcogenyl)propane-1,2-diols in excellent yields.

PEG-400 was used as a green and recyclable solvent in an efficient, simple and straightforward method for the synthesis of β-arylthio-α,β-unsaturated esters, ketone and aldehyde through the hydrothiolation of alkynes with arylthiols under base- and catalyst-free conditions. The reactions were performed under mild conditions and furnished selectively the respective ( Z )-β-arylthio-α,β-unsaturated compounds from alkynyl esters and ketone, while from alkynyl aldehyde, the ( E )-stereoisomer was obtained, in good yields and moderate reaction times. PEG-400 was reused in up 5 successive reactions without previous treatment, affording products in comparable yields.

Bearing in mind that pain and major depressive disorder (MDD) often share biological pathways, this condition is classified as depression-pain syndrome. Mounting evidence suggests that oxidative stress is implicated in the pathophysiology of this syndrome. The development of effective pharmacological interventions for the depression-pain syndrome is of particular importance as clinical treatments for this comorbidity have shown limited efficacy. Therefore, the present study aimed to evaluate whether the 3,5-dimethyl-1-phenyl-4-(phenylselanyl)-1H-pyrazole (SePy) was able to reverse the depression-pain syndrome induced by intracerebroventricular (i.c.v) streptozotocin (STZ) in mice and the possible modulation of oxidative and nitrergic pathways in its effect. The treatment with SePy (1 and 10 mg/kg) administered intragastrically (i.g.) reversed the increased immobility time in the tail suspension test, decreased grooming time in the splash test, latency time to nociceptive response in the hot plate test, and the response frequency of Von Frey hair (VFH) stimulation induced by STZ (0.2 mg/4 μl/per mouse). Additionally, SePy (10 mg/kg, i.g.) reversed STZ-induced alterations in the levels of reactive oxygen species, nitric oxide, and lipid peroxidation and the superoxide dismutase and catalase activities in the prefrontal cortices (PFC) and hippocampi (HC) of mice. Treatment with SePy (10 mg/kg, i.g.) also reversed the STZ-induced increased expression of inducible nitric oxide synthase (iNOS) and glycogen synthase kinase 3 beta (GSK3β) in the PFC and HC. An additional molecular docking investigation found that SePy binds to the active site of iNOS and GSK3β. Altogether, these results indicate that the antidepressant-like effect of SePy is accompanied by decreased hyperalgesia and mechanical allodynia, which were associated with its antioxidant effect.

4-(Arylchalcogenyl)-1H-pyrazoles containing selenium or sulfur (0.001-50 mg/kg) were investigated regarding the intragastric route effect (ig) administration on nociception in mice. In this study, nociception and inflammation were induced by chemical agents such as formalin (0.92%), sodium L-glutamate 1-hydrate (20 μmol), croton oil (2.5%), acetic acid (1.6%) and thermic model with a hot plate test.Compounds 1a-c had the ability to reduce licking time in both phases (neurogenic and inflammatory) of the formalin test and glutamate. Only compounds 1a and 1b had the ability to reduce the number of abdominal writhes caused by acetic acid. The same was observed with the positive control celecoxib. To evaluate the possible anti-inflammatory activity of compounds 1a-c, the induction of paw edema by formalin and ear edema by croton oil was performed. For the inflammation induced by formalin, significant effects were observed from the dose of 0.1 mg/kg (1a-b) and 10 mg/kg (1c). In the ear edema test, it can be observed that only compound 1a had a significant effect. In the hotplate test, all the compounds had the ability to reduce the latency time.The results demonstrated that acute antinociceptive and anti-inflammatory effects of 4-(arylchalcogenyl)-1H-pyrazoles 1a is better than compared with the compound 1b and 1c in mice. This resulted in these molecules attracting the interest of researchers to perform future studies to develop new drugs to treat pain and inflammatory clinical conditions.

A green methodology to synthesize 2-organoselanyl-naphthalenes based on the reaction of alkynols with diaryl diselenides is described. The electrophilic species of selenium were generated in situ, by the oxidative cleavage of the Se–Se bond of diaryl diselenides by Oxone® using water as the solvent. The reactions proceeded efficiently under ultrasonic irradiation as an alternative energy source, using a range of alkynols and diorganyl diselenides as starting materials. Through this methodology, the corresponding 2-organoselanyl-naphthalenes were obtained in moderate to good yields (56–94%) and in short reaction times (0.25–2.3 h).

Organochalcogen compounds (containing S, Se and Te) are interesting either for use as an intermediate in the synthesis of complex molecules or for the exploitation of their biological properties. The growing in the number of papers on the synthesis and application of organochalcogen compounds has been accompanied by a concern about how they are prepared. Here, we provide a comprehensive and updated review on recent synthetic methods available for their synthesis using alternative solvents or solvent-free conditions and non-classical energy sources (microwaves irradiation, sonochemistry and mechanochemistry). Organized in fourteen sections, this review brings the more than one hundred alternative methods described so far to access organic compounds containing selenium, tellurium and sulfur.

Herein we describe the reaction between the nucleophilic species of chalcogenium (sulfur, selenium and tellurium) and (R)- and (S)-solketal tosylates to prepare enantiomerically pure bis-1,3-dioxolanylmethyl chalcogenides and dichalcogenides in short reaction times and good yields. Furthermore, the new diselenide 4a was evaluated in the Michael reaction with acrylonitrile, giving (R)-3-[(2,3-dihydroxypropyl)selanyl]propanenitrile 6b after two steps.

We describe herein an efficient protocol to synthesize selanyl-substituted pyrazoles by cyclocondensation and copper-catalyzed direct CH bond selenation reactions. The products were obtained in moderate to excellent yields by the one-pot multicomponent reactions of hydrazines, 1,3-diketones and diorganyl diselenides, using catalytic amounts of copper bromide and bipyridine. These reactions tolerated a range of substituents in the starting materials and proved to be an efficient methodology for combinatorial synthesis of new selenium-containing pyrazoles with potential applications in biological studies.

An alternative green method was described for the synthesis of selanylesters by reactions of acyl chlorides with arylselenols, generated in situ by reaction of diaryl diselenides with hypophosphorous acid (H3PO2) using polyethylene glycol-400 (PEG-400) as the solvent. These reactions proceeded efficiently at room temperature under N2 using a range of acyl chlorides and diaryl diselenides, both containing electron-withdrawing and electron-donating groups, affording the corresponding selanylesters in moderate to excellent yields. Additionally, PEG-400 can be recovered and directly reused for further reactions.

Herein we describe the results on the synthesis and the evaluation of the antioxidant activity of several organochalcogen-containing chrysin derivatives (Se and Te). The semi-synthetic compounds were easily synthesized in good to excellent yields by the reaction of 7-(2-bromoethoxy)-chrysin with nucleophilic organoselenium and organotellurium species. The antioxidant properties of Se- and Te-containing chrysin derivatives were evaluated by three different in vitro assays, the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and ferric ion reducing antioxidant power (FRAP). Compounds 4i (which contains the butyltellurium moiety) and 4j (which contains a 4-phenyltellurium moiety) exhibited higher activities than chrysin and the selenium analogues, with compound 4i being the most potent antioxidant.

Background: The main constituents of Cymbopogonnardus (L) Rendle and C. citratus (DC) Stapfessential oils are (R)-citronellal and citral, respectively. Organochalcogen compounds can boost the biological activities of natural products. Methods: Several chalcogen-containing nitrones derived from (R)-citronellal and citral were prepared and evaluated for their antimicrobial and antioxidant activities. The antimicrobial activity was evaluated by the disc diffusion test and the antioxidant properties were evaluated in vitro by DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), and FRAP (ferric ion reducing antioxidant power) assays. Results: In the antimicrobial assay, (E)-N,3,7-trimethyl-3-(phenylthio)oct-6-en-1-imine oxide 5c exhibited halos between 21.5 mm (Escherichia coli O157:H7) and 26.0 mm (Listeria monocytogenes), while (E)-N,3,7-trimethyloct-6-en-1-imine oxide 5d presented halos between 22.5 mm (E. coli O157:H7) and 31.0 mm (L. monocytogenes). (E)-N,3,7-Trimethyl-2-(phenylthio)oct-6-en-1-imine oxide 5a showed the lowest minimal inhibitory concentration (MIC) value against Bacillus cereus (0.48 mM), and 5c was the most potent bactericide, with a minimal bactericidal concentration (MBC) of 0.52 mM for E. coli O157:H7. In the antioxidant assays, 5c, 5d, and 10 ((E)-3,7-dimethyl-2-(phenylselanyl)oct-6-enal oxime) were the most actives in the DPPH, ABTS, and FRAP assays, respectively. Conclusions: The presence of a phenylthio group in the nitrone increases its antimicrobial activity against Gram-positive and Gram-negative foodborne pathogens in the disk diffusion test and the antioxidant activity in vitro.

In order to investigate the use of semi-synthetic antimicrobial compounds, the objective of this study was to evaluate the 3-(p-chlorophenyl)thio citronellal, a novel compound that is derived from the essential oil of Cymbopogon citratus, against spoilage and pathogenic bacteria in food. This study also evaluated the possible mechanisms of action and cellular targets. Qualitative and quantitative tests and scanning electron microscopy were used to compare 3-(p-chlorophenyl)thio citronellal with citral and (R)-citronellal. It was observed that 3-(p-chlorophenyl)thio citronellal is a potent antimicrobial agent with bactericidal activity against different pathogenic and spoilage bacteria, of which the Gram-positive species were the most sensitive. The minimal inhibitory concentration for 3-(p-chlorophenyl)thio citronellal was approximately 100 times lower than that of citral, and this was corroborated by the kinetic curve of action, demonstrating that cell death was faster when the bacterial cells were treated with 3-(p-chlorophenyl)thio citronellal. This finding showed that the addition of thiol enhances the bioactivity of citral. In vitro testing showed that the compound does not show toxicity. The SEM images showed cell damage with the formation of pores in the cell wall and membrane, which are possibly the cellular targets of the compound.

Psidium cattleianum Sabine (Myrtacea) is rich in vitamin C and phenolic compounds, including epicatechin and gallic acid as the main components.To evaluate the antifungal and antioxidant capacity in vitro of the essential oil of araçá (EOA). The acute toxicity of the EOA also was evaluated in mice.The leaves of the P. cattleianum were extracted by steam distillation. The antioxidant capacity was evaluated by in vitro tests [1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), ferric ion reducing antioxidant power (FRAP), linoleic acid oxidation, thiobarbituric acid reactive species (TBARS)], and ex vivo analysis [TBARS, δ-aminulevunilate dehydratase (δ-Ala-D) and catalase activity, non-protein thiols (NPSH), and ascorbic acid levels]. The toxicity was studied in mice by a single oral administration of EOA; and the antifungal activity was performed with five strains of fungi.The EOA exhibited antioxidant activity in the FRAP assay and reduced lipid peroxidation in the cortex (Imax = 32.90 ± 2.62%), hippocampus (IC50 = 48.00 ± 3.00 µg/ml and Imax = 32.90 ± 2.62%), and cerebellum (Imax = 45.40 ± 14.04%) of mice. Acute administration of the EOA by the oral route did not cause toxicological effects in mice (LD50 500 µg/ml). The EOA also showed antifungal activity through of the determination minimum inhibitory concentration (MIC) values ranging from 41.67 ± 18.04 to 166.70 ± 72.17 µg/ml for tested strains.The results of present study indicate that EOA possess antioxidant properties, antifungal and not cause toxicity at tested doses.

Streptococcus mutans is the primary bacteria involved in caries. To prevent this disease, fluoride compounds are used; however, these compounds can become toxic at certain concentrations. The purpose of this study was to evaluate the antimicrobial activity of essential oils (Eos) from two eucalyptus species (Eucalyptus globulus and Eucalyptus urograndis) against planktonic and biofilm cells of S. mutans using the agar diffusion assay and by determining the minimum inhibitory concentrations, kinetic of action and ability to inhibit biofilm formation. The synergistic effect of the combined oils was also tested (1:1). Films constructed of biodegradable starch with the EOs were prepared, and their bioactivity was tested using the macrodilution technique. These essential oils were active against S. mutans, and they presented inhibition zones between 14.7 ± 1.2 mm and 35.3 ± 0.34 mm in diameter. It was observed that when the oils were used together, there was an increase in bioactivity. The kinetics of loss of cell viability test showed a reduction of 1 log cycle in the microorganism counts within less than 5 min of contact time. The essential oil from E. globulus gave the best results, requiring only 15 min of contact to cause microbial death; E. urograndis oil required 50 min to induce the same bactericidal effect. These results can be explained by the larger concentration of 1,8-cineole in the EO of E. globulus. Biofilm formation by S. mutans was also inhibited in the presence of the tested oils, which yielded more effective results when compared to 0.1% commercial NaF (sodium fluoride). The increased bioactivity of these oils suggests their technological potential.

We describe herein our results on the organocatalytic synthesis and pharmacological properties of 7-chloroquinoline-1,2,3-triazoyl carboxamides. This class of compounds was synthesized in good to excellent yields by the reaction of 4-azido-7-chloroquinoline with a range of β-oxo-amides in the presence of a catalytic amount of pyrrolidine (5 mol%). The obtained compound 3a was screened for anticonvulsant, antinociceptive and anti-inflammatory activities in vivo. The results demonstrated that compound 3a was effective in decreasing the appearance of seizures induced by pilocarpine and pentylenetetrazole. In addition, compound 3a demonstrated antinoceptive and anti-inflammatory properties for combating acute pain. This protocol is an efficient method for the production of new heterocyclic compounds with pharmacological activities.

This work aimed to evaluate the bioactivity of 3-(p-chlorophenyl)thio citronellal against planktonic and biofilm cells of S. aureus and its use in biodegradable films. 3-(p-chlorophenyl)thio citronellal demonstrated antimicrobial activity against planktonic (MIC = 62.5 ± 0.5 μg.mL−1) and biofilm cells of S. aureus. Regarding barley starch films containing 3-(p-chlorophenyl)thio citronellal, after 4 h of contact there was a difference of 5 log CFU.mL−1 in relation to control film (without additives). The films prepared with 3-(p-chlorophenyl)thio citronellal and citral (its precursor) were more opaque and had lower tensile strength than the control film. However, the addition of the 3-(p-chlorophenyl)thio citronellal in the film had lower effect on the water solubility and tensile strength than the addition of citral. 3-(p-chlorophenyl)thio citronellal have activity against planktonic and biofilm cells of S. aureus and could be applied in biodegradable films as an alternative to inhibit the microbial growth on the surface of food, enhancing food safety.

We present herein our results on the nucleophilic addition of imidazole to a range of arylselanylalkynes by simple heating in DMF without any additives to give ( Z )-1-(1-organyl-(2-arylselanyl)vinyl)-1H-imidazoles. The reactions were performed under mild conditions with a range of arylselanylalkynes in good yields and with high regio- and stereoselectivity to give the respective (Z)-arylselanyl alkene as the only isomer.

We describe herein the use of glycerol as an efficient and recyclable solvent for the addition of thiols to nonactivated alkenes. The catalyst-free reactions take place easily using glycerol at room temperature or heating and the corresponding linear thioethers were obtained in good to excellent yields. The method was used to synthesize new sulfur-containing eugenols, which were tested for their antioxidant activities. The semisynthetic thio-derivatives were more effective in inhibition of induced lipid peroxidation compared to the precursor eugenol and the synthetic antioxidant butylated hydroxyanisole.

Imine-modified silicas were synthesized by the reaction of the essential oil of Eucalyptus citriodora , 3-aminopropyltriethoxysilane and tetraethylorthosilicate by different methods. The imine supported on silica was characterized by FT-IR-spectroscopy using the attenuated total reflection (ATR) technique, the Brunauer–Emmett–Teller (BET) method and thermogravimetric analysis (TGA). These silicas have shown a large amount of organic matter incorporated on the surface, which affects their textural properties. The hydrolysis reaction of the imine-modified silica leads to the formation of products different from those expected.

A convenient approach to the Cu-catalyzed coupling of diphenyl disulfide and diphenyl ditelluride with vinyl bromides using a recyclable catalytic system and glycerol as a green solvent is described. This protocol was efficiently used in the preparation of vinyl sulfides and vinyl tellurides with a variety of substituents in good yields and stereoselectively. The solvent/catalyst system was directly reused for four cycles without loss of activity.

The ionic liquid 1-butyl-3-methylimidazolium methylselenite, [bmim][SeO2(OCH3)], was successfully used as solvent in the catalyst-free preparation of 3-arylselenylindoles by the reaction of indole with ArSeCl at room temperature. The products were obtained selectively in good yields without the need of any additive and the solvent was easily reused for several cycles with good results.

A simple and efficient protocol to prepare divinyl selenides has been developed by the regio- and stereoselective addition of sodium selenide species to aryl alkynes. The nucleophilic species was generates in situ, from the reaction of elemental selenium with NaBH4, utilizing PEG-400 as the solvent. Several divinyl selenides were obtained in moderate to excellent yields with selectivity for the (Z,Z)-isomer by a one-step procedure that was carried out at 60 °C in short reaction times. The methodology was extended to tellurium, giving the desired divinyl tellurides in good yields. Furthermore, the Fe-catalyzed cross-coupling reaction of bis(3,5-dimethoxystyryl) selenide 3f with (4-methoxyphenyl)magnesium bromide 5 afforded resveratrol trimethyl ether 6 in 57% yield.

Organochalcogen compounds (containing S, Se and Te) are interesting either for use as an intermediate in the synthesis of complex molecules or for the exploitation of their biological properties. The growing in the number of papers on the synthesis and application of organochalcogen compounds has been accompanied by a concern about how they are prepared. Here, we provide a comprehensive and updated review on recent synthetic methods available for their synthesis using alternative solvents or solvent-free conditions and non-classical energy sources (microwaves irradiation, sonochemistry and mechanochemistry). Organized in fourteen sections, this review brings the more than one hundred alternative methods described so far to access organic compounds containing selenium, tellurium and sulfur.

The use of choline chloride/urea as a deep eutectic solvent (DES) in the synthesis of vinyl selenides is described.

The title compounds were synthesized by a one-pot reaction of diaryl diselenides with terminal alkynes avoiding the previous preparation of arylselanyl alkynes. The reactions were performed under mild conditions with a range of terminal alkynes using KF/Al2O3 and PEG-400 as solvent. The addition of diaryl diselenides to alkynes occurred stereoselectively to give exclusively (Z)-1,2-bis-arylselanyl alkenes in good yields. The reaction time was reduced to a few minutes using microwave irradiation and the KF/Al2O3/PEG-400 system can be reused one time without previous treatment with comparable activity.

Here we describe a simple, clean, and efficient solvent-free protocol for the synthesis of bis(indolyl)methanes promoted by silica gel. The products were obtained in good to excellent yields through the reaction of indoles with cyclohexanone and a range of aldehydes. The silica gel was easily recovered and utilized for further reactions without loss of activity.

Essential oil (EO) of the leaves of Eugenia uniflora L. (Brazilian cherry tree) was evaluated for its antioxidant, antibacterial and antifungal properties. The acute toxicity of the EO administered by oral route was also evaluated in mice. The EO exhibited antioxidant activity in the DPPH, ABTS and FRAP assays and reduced lipid peroxidation in the kidney of mice. The EO also showed antimicrobial activity against two important pathogenic bacteria, Staphylococcus aureus and Listeria monocytogenes, and against two fungi of the Candida species, C. lipolytica and C. guilliermondii. Acute administration of the EO by the oral route did not cause lethality or toxicological effects in mice. These findings suggest that the EO of the leaves of E. uniflora may have the potential for use in the pharmaceutical industry.

In this study, the antioxidant and antidepressant-like effects of α-(phenylselanyl) acetophenone (PSAP), an organoselenium compound, were investigated. To assess the in vitro antioxidant properties, PSAP was evaluated in four test systems (DPPH, ABTS, FRAP and inhibition of lipid peroxidation). PSAP (100-500 μM) showed potent antioxidant activity and protected against lipid peroxidation. Additionally, we investigated whether PSAP, when administered in mice (100, 200 and 400mg/kg, per oral, p.o.), could cause acute toxicity. Our results demonstrated that PSAP did not cause the death of any animal, significantly reduce body weight or cause any oxidative tissue stress following treatment. This study also evaluated the effect of PSAP (0.1-10 mg/kg, p.o) on mice in a forced swim test (FST) and tail suspension test (TST), assays that are predictive of depressant activity and motor activity in the open-field. PSAP (5-10 mg/kg) significantly reduced immobility time in the FST and TST without affecting motor activity. In addition, the antidepressant-like effect caused by PSAP (5m/kg, p.o) in mice during the TST was dependent on an interaction with the serotonergic system (5-HT(1A) receptors), but not with the noradrenergic, dopaminergic or adenosinergic system. Together, these results suggest that PSAP possesses antioxidant and antidepressant-like properties and may be of interest as a therapeutic agent for the treatment of depressive disorders.

In this work we performed studies on the antimicrobial activities of α-phenylseleno citronellal and α-phenylseleno citronellol, two new selenium-containing citronella oil derivatives. The presence of phenylselenium group in the citronellal molecule increased antimicrobial activity, as compared to a natural, unsubstituted terpene. We assessed the antimicrobial activity of each compound against three important species of foodborne pathogenic bacteria: Listeria monocytogenes, Staphylococcus aureus and Salmonella Typhimurium, using the agar diffusion method and by measuring the minimum inhibitory concentration, all the tested compounds showed antimicrobial activity against the three bacteria used. The modified aldehyde showed good values of a minimum inhibitory concentration of 0.03 mM and antimicrobial activity against Salmonella Typhimurium at 6.400 arbitrary units per milliliter (AU/mL). The identification of the antimicrobial properties of compounds derived from citronella suggests that the use of these substances to protect food against pathogenic bacteria deserves further exploration.

We present here a clean and fast synthesis of organic disulfides starting from thiols using glycerol as solvent under microwave irradiation. This efficient method is general for aromatic, aliphatic, and functionalized thiols, affording the corresponding disulfides in good to excellent yields after easy work up. Glycerol can be easily recovered and utilized for further oxidation reactions.

A general and easy method for the synthesis of several 1-H-1,5-benzodiazepines using SiO2/ZnCl2 under solvent-free conditions is described. This efficient and improved method furnishes selectively and in good yields the corresponding 1-H-1,5-benzodiazepines derivatives starting from o-phenylenediamine and cyclic or acyclic ketones. The catalytic system was reused up four times, and the use of focused microwaves accelerates the reaction. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:180–185, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20674

A general and simple method for the synthesis of vinyl selenides and tellurides starting from terminal alkynes and diorganyl chalcogenides using NaBH4 and [bmim]BF4 as a recyclable solvent was developed. This efficient and improved method furnishes the corresponding vinyl chalcogenides preferentially with Z configuration. We also observed that when the same protocol was applied to phenyl acetylene, (E)-bis-phenylchalcogeno styrenes were obtained in good yields and high selectivity. The ionic liquid was reused up three times without lost of efficiency. Um método simples e geral foi desenvolvido para a síntese de selenetos e teluretos vinílicos a partir de alquinos terminais e dicalcogenetos de diorganoíla usando NaBH4 e [bmim]BF4 como solvente reciclável. Este método eficiente permite a formação preferencial de calcogenetos vinílicos de configuração Z na maioria dos exemplos estudados. Também foi observado que na reação envolvendo fenilacetileno, (E)-bis-fenilcalcogenoestirenos foram obtidos com bons rendimentos e alta seletividade. O líquido iônico foi reutilizado três vezes sem perda da eficiência.

PEG-400 and glycerin were successfully used as recyclable solvents for the synthesis of several alkenyl selenides and tellurides, in good yields and with high selectivity by the hydrochalcogenation of terminal alkynes. The nucleophilic species of selenium and tellurium were generated in situ from the reaction of the respective diphenyl dichalcogenide with NaBH4 at 60 °C. This easy, general and improved method furnishes the corresponding alkenyl chalcogenides preferentially with Z configuration. The PEG-400 can be reused up to 4 times without previous treatment with comparable yields and selectivity.

Here we present a simple, solvent-free, one-pot, hetero-Diels–Alder reaction of (R)-citronellal or 3-(phenylthio)-citronellal with arylamines using solid-supported catalyst (SiO2/ZnCl2). This general, efficient, and improved method is selective, affording preferentially new trans-fused 3-(phenylthio)-octahydroacridines (S-OHAs) in good yields. The use of microwave irradiation facilitates the procedure and accelerates the reaction.