It has been declared frequently that valerian may potentiate the effect of other central nervous system (CNS) depressant drugs, however there has been a lack of experimental data. We have evaluated the profile of the interactions between the ethanol extract of Valeriana edulis spp procera and six CNS depressant drugs using an exploratory model to test the sedative effect in mice. All the compounds tested showed a dose-dependent sedative effect with the following ED50 values: valerian 181.62, diazepam 1.21, ethanol 1938, pentobarbital 11.86, buspirone 1.04, haloperidol 0.41 and diphenhydramine 17.06 mg kg-1. An isobolographic analysis was used to evaluate the sedative interaction of the intraperitoneal co-administration of 1:1 fixed-ratio combination of equi-effective doses of valerian extract with each CNS depressant drug. The ED50 theoretical (Zadd) and experimental (Zexp) for each combination were: valerian+diazepam,Zadd=91.41 mg kg-1, Zexp=81.64 mg kg-1; valerian+ethanol, Zadd=1060.22 mg kg-1, Zexp=687.89 mg kg-1; valerian+pentobarbital, Zadd=96.74 mg kg-1, Zexp=151.83 mg kg-1; valerian+buspirone, Zadd=91.33 mg kg-1, Zexp=112.73 mg kg-1; valerian+haloperidol, Zadd=91.01 mg kg-1, Zexp=91.52 mg kg-1; valerian+diphenhydramine, Zadd=99.34 mg kg-1, Zexp=123.52 mg kg-1. Neither synergistic nor attenuate effects were found in any of the combinations evaluated. We concluded that the valerian extract did not potentiate the sedative effect of commonly prescribed CNS depressant drugs as was expected. The additive effect found through the isobolographic analysis suggested that the sedative effect of V. edulis resulted from the activation of common mechanisms of haloperidol, diazepam, buspirone, pentobarbital, diphenhydramine and ethanol.

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Ethyl 3‐[3H‐1,5‐benzodiazepin‐2‐yl]carbazates II were prepared in moderate yields from the title compounds and ethyl carbazate. The compounds II were easily transformed into 1H‐s‐triazolo[4,3‐a][1,5]benzodiazepin‐1‐ones III via a one‐step procedure. Reaction of triazolo‐1,5‐benzodiazepinones III with sodium hydride in methyl iodide gave a mixture of products from which were isolated two compounds IV and V. The structure of all products was confirmed by ir, 1H nmr and mass spectrometry.

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Noble metals nanoparticles have a great scientific and industrial interest due to their wide range of possible applications in nanotechnology and catalysis [1]. The chemical synthesis methods like sol-gel, seem to offer some advantages over other physical, being the size control of the nanoparticles one of the most important. Normally, the chemical methods start for the reduction of the metallic precursor in the presence of the solvent; this helps to disperse the particles, and finally, the addition of any polymer such as acrylamide, in order to control the growth of the metal particles.[2]The synthesis of rhodium nano-crystals was carried out by sol-gel method with the addition of acrylamide [3]. The rhodium metal was dissolved in sulfuric acid and distilled water at ~ 70 ° C, forming a yellowish solution. Once the solution reached room temperature, the pH is adjusted at ~ 7 by adding NH4OH. Immediately after a pH of ~ 7 was obtained, Ethylenediaminetetraacetic acid (EDTA), acrylamide N-N' metilenebisacrylamide and -' azodiisobutyramidine dihydrochloride was added using a stoichiometric ratio of 1:1:5:0.2. Then, the polymerization was done at 80 ° C for 3 s, under constant agitation. Once obtaining the gel, this was placed in a microwave system for its decomposition. In order to produce the xerogel, thermal decomposition was carried out under an argon flow for 30 minutes from room temperature to 170 ° C. Thereafter, the resultant material was pulverized using an agate mortar and finally heated up to 1000 ± 4 ° C for 2 h in air.The powder X-ray diffraction of the material is shown Figure 1. The three specific characteristic peaks of pure Rhodium, in angles 2 =41.02, 47.7 y 69.8º, corresponding to its cubic structure (PDF file 089-7383), were observed. The SEM images showed in Figure 2 (a) and (b) display a morphology of the material resembling to type pores and agglomerates formed by nano-crystals in size between 200 nm and 1 m. Figures 3 (a) and (b), show the TEM micrographs of the material. The large particles detected in SEM observations are actually clusters, probably produced after sintering, from agglomerated Rh crystals (of ~ 15 nm). Thus, pure Rh nano-crystals were obtained easily with the proposed method in this work.

An improved acrylamide sol-gel technique using a microwave oven in order to synthesize bimetallic Rh-Pd particles is reported and discussed. The synthesis of Pd and Rh nanoparticles was carried out separately. The polymerization to form the gel of both Rh and Pd was carried out at 80°C under constant agitations. The method chosen to prepare the Rh and Pd xerogels involved the decomposition of both gels. The process begins by steadily increasing the temperature of the gel inside a microwave oven (from 80°C to 170°C). In order to eliminate the by-products generated during the sol-gel reaction, a heat treatment at a temperature of 1000°C for 2 h in inert atmosphere was carried out. After the heat treatment, the particle size increased from 50 nm to 200 nm, producing the bimetallic Rh-Pd clusters. It can be concluded that the reported microwave-assisted, sol-gel method was able to obtain nano-bimetallic Rh-Pd particles with an average size of 75 nm.