Leaves of Maytenus robusta (Celastraceae) were subjected to phytochemical investigation mainly directed at the isolation of pentacyclic triterpenes. The compounds friedelin (1), β-friedelinol (2), 3-oxo-21β-H-hop-22(29)-ene (7), 3,4-seco-friedelan-3,11β-olide (8), 3β-hydroxy-21β-H-hop-22(29)-ene (9), 3,4-seco-21β-H-hop-22(29)-en-3-oic acid (10), 3,4-seco-friedelan-3-oic acid (11), and sitosterol were identified in the hexane extract of M. robusta leaves. Compounds 8 and 9 are described herein for the first time. The structure and stereochemistry of both compounds were experimentally established by IR, HRLC-MS, and 1D (1H, 13C, and DEPT 135) and 2D (HSQC, HMBC and COSY) NMR data and supported by correlations with carbon chemical shifts calculated using the DFT method (BLYP/6-31G* level). Compounds 7 and 10 are also described for the first time, and their chemical structures were established by comparison with NMR data of similar structures described in the literature and correlations with BLYP/6-31G* calculated carbon chemical shifts. Compound 9, a mixture of 11 and sitosterol, and 3β,11β-dihydroxyfriedelane (4) were evaluated by the Ellman’s method and all these compounds showed acethylcholinesterase inhibitory properties.

Abstract:The phytochemical investigation on the aereal parts of Lychnophora pinaster Mart., Asteraceae, was carried to isolation of triterpenes. 3-O-Acetyllupeol (1), 3-O-acetyl-pseudotaraxasterol (2), and 3-O-acetyl-α-amyrin (3) were isolated from hexanic extract and 4,4-dimethyl-cholesta-22,24-dien-5-ol (4), α-amyrin (5), and lupeol (6) were isolated from hexanic/dichlorometanic extract of the leaves. Compounds Δ 7 -bauerenyl acetate (7), friedelin (8), stigmasterol (9), and sitosterol (10) were isolated from the hexanic/dichlorometanic extract of the stems. The steroids 9 and 10 were also isolated from the hexanic/dichlorometanic extract of the flowers. Triterpenes 1, 3, 4, and 7 are described for the first time in the genus Lychnophora. The apolar fractions of the leaf and stem extracts and some isolated triterpenes showed low trypanocidal activity. Moreover, apolar fractions of the leaf and stem extracts and 5 showed antibacterial action against Staphylococcus aureus.

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The goal of this work was to explore the chemistry and the physics of a family of molecule-based magnets containing three spin carriers, with a fully interlocked structure. The main emphasis was on the coercivity of these magnets, which confers a memory effect on the materials. stands for the radical cation 2-(1-ethylpyridinium-4-yl)-4,4,5,5-tetramethylimidazolin-1-oxyl-3-oxide, and opba stands for ortho-phenylenebis-(oxamato). The crystal structures of the three compounds have been determined. The structure of 1 consists of planar Cu(opba) units with one of the radical cations weakly bound to the Cu 2 ion, the other radical cation being rather isolated. Compounds 2 and 3 are isomorphous. Their structure consists of two interpenetrating graphitelike networks with edge-sharing hexagons. The magnetic properties of the three compounds have been investigated in detail. For compounds 2 and 3 the temperature dependences of the direct current (dc) and alternating current (ac) magnetic responses have been measured along with the field dependence of the magnetization. Both compounds exhibit a long-range magnetic ordering with a spontaneous magnetization. The critical temperatures are 22.8 K and 37 K for 2 and 3, respectively. While 2 is a soft magnet, 3 has been found to be a very hard magnet, with a coercive field depending on the particle size. This coercive field may reach 24 kOe at 6 K for a sample consisting of very small crystals. Mixed materials with the abbreviated formula [Etrad 2 Mn 2À2x Co 2x Cu 3 ] (4Àx) have also been synthesized. Their critical temperatures have been found to vary almost linearly with x. The x dependence of the coercive field has also been investigated and analyzed.

BackgroundLycnophora pinaster is used by the traditional Brazilian medicine for the treatment of inflammations. Anti-inflammatory activity of Lycnophora pinaster was investigated for extracts, fractions, and isolated compounds of their aerial parts. The hexane extract (HE) provided α-amyrin, lupeol, mixture of α-amyrin and lupeol, mixture of 3-O-acetyl-lupeol and 3-O-acetyl-pseudotaraxasterol, and mixture of the steroids stigmasterol and sitosterol. The aqueous extract (WE) provided a fraction containing alkaloids (AF) and another one containing phenolic compounds (PF).MethodsThe crude hexane extract obtained from aerial parts of L. pinaster was submitted to chromatographic fractionation. The fractionation of PF was performed by preparative HPLC analysis, providing the flavonoid quercetin. The extracts, fractions, and compounds isolated from L. pinaster were tested to evaluate the anti-inflammatory activity by experimental model of impact injury, followed by transdermal application of gels with these samples. The application of the gels was performed using phonophoresis in rat paws after induction of muscle injury. Histological analysis was based on scores assigned by the capacity of decreasing the lesion.ResultsHE and WE exhibited anti-inflammatory activity. Some fractions, triterpenes, and steroids also reduced the inflammatory infiltrates caused by muscle injury. Lupeol promoted a significant reduction of inflammation. Quercetin also provided significant results, promoting the greatest decreases in muscle injury.ConclusionThe results of this work suggest that topical application of triterpenes, steroids and flavonoid significantly decreases the inflammatory process generated by muscle injury. The transdermal application using phonophoresis in rat paws of gel with lupeol and quercetin attenuates the inflammation.

Neste trabalho, descrevemos a obtenção de dois novos compostos de cobre(II), ou precursores, (Pr-Rad) 2 3DMSO.6H 2 O (4), respectivamente. As propriedades magnéticas dos precursores 1 e 2 mostram a presença de interações ferromagnéticas entre os radicais cátions e o cobre (II), na faixa de temperatura entre 20 e 300 K. Os magnetos moleculares 3 e 4 exibem magnetização espontânea com temperatura crítica, T c , de 23 K e 24 K, respectivamente.In this work, we describe the synthesis of two new copper(II) compounds, (Pr-Rad) 2 [Cu(opba)].H 2 O (1) and (Bu-Rad) 2 [Cu(opba)].2H 2 O (2) where opba stands for orthophenylenebis(oxamato) and R-Rad + are nitronyl nitroxide radical cations. From 1 and 2, two new molecule-based magnets [Pr-Rad] 2 [Mn 2 {Cu(opba)} 3 ].3.3DMSO.5H 2 O (3) and [Bu-Rad] 2 [Mn 2 {Cu(opba)} 3 ].3DMSO.6H 2 O (4) were obtained, respectively. The magnetic properties of precursors 1 and 2 show the presence of ferromagnetic interaction between the radical cations with copper(II), in the temperature range of 20-300 K. The magnets 3 and 4 exhibit spontaneous magnetization at critical temperatures, T c , of 23 K and 24 K, respectively. Keywords: supramolecular chemistry, molecule-based magnets, molecular materials, catenanes, ferrimagnetism IntroductionAs evidenced by the remarkable increase in publications on the topic, the field of molecule-based magnetism is flourishing. However, the critical temperature of the molecule-based magnets remains low and up to now there have not been compounds of this type used for any technological application. Four molecule-based magnets have been reported to remain magnetically ordered near room temperature.1-3 One of them decomposes at 350 K, and the other three demagnetize near 315 K. The crystal structures of these compounds have not all been determined.One of the outstanding features of molecule-based materials is that the magnetic properties may be transformed by quite small and subtle modifications in the molecular chemistry. Variations in the organic molecules may lead to modifications in the magnetism of the material. Sometimes the molecular fragments only serve as spacers and are not involved directly in the interaction between neighboring atoms. 4 In other cases, the organic part, although not possessing magnetic moment or not being responsible for the transmission of the interaction is essential to the exchange process. 5 In the last few years, numerous magnetic molecular units carrying spin and able to establish 3 ], (pbaOH = 2-hydroxy-1,3-propylenebis(oxamato)) with T c = 4.6 K.In the beginning of the nineties, we initiated a research in the direction to increase the dimensionality of the compounds using a more 'organic' building block: [Cu(opba)] 2-where opba stands for ortho-phenylenebis(oxamato) (see Figure 1a). We succeeded in designing two-dimensional magnets of formula [cat] Figure 1b). This compound, a magnet with T c of 22 K, presents a rare interlocked structure. Moreover, by the time of the description of this compound, no molecular magnet...

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