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Agave marmorata Roezl is an endemic succulent specie from the Oaxaca-Puebla area of Mexico. This plant is a medicinal recourse and contain a rich variety of saponins-type compounds with multiples b...

Muchas de las propiedades y funciones que presenta un compuesto químico, son propiedades de su estructura; su conformación molecular le confiere propiedades únicas con enormes aplicaciones en química, biología, farmacia, ciencia de materiales, etc. La espectroscopía de Resonancia Magnética Nuclear (RMN) se ha consolidado como una herramienta clave para conocer la estructura tridimensional de las moléculas. Esta técnica provee información detallada sobre la dinámica y el ambiente químico que rodea a las moléculas. El desarrollo vertiginoso de su teoría y el gran avance tecnológico han hecho posible que puedan estudiarse e identificarse estructuras tridimensionales de proteínas de más de 800 residuos con gran precisión. En el presente capítulo, se pretende dar un panorama general del “fenómeno de la RMN”, haciendo énfasis en los principios básicos de su teoría.

Phytochemical research of the acetate and methanol extracts of the aerial parts (flowers, leaves and stems) of Salvia elegans allowed to obtain seventeen known compounds (1-17): three of them (4, 5, 14), had already been described for this species, while the others (1-3, 6-13, 15-17) are described for the first time for S. elegans. All isolated compounds were characterized using spectroscopic techniques and mass spectrometry and were evaluated in the Angiotensin I-converting enzyme (ACE) inhibition model, where the phenolic compounds (13, 14 and 15) had the same inhibitory effect as lisinopril at 0.02 mg/mL. The terpenes showed a moderate inhibitory capacity at a concentration of 0.2 mg/mL.

Salvia tiliifolia Vahl (Lamiaceae) is used for the empirical treatment of pain and inflammation. The diterpenoid tilifodiolide (TFD) was isolated from Salvia tiliifolia. The in vitro anti-inflammatory effects of TFD (0.1-200 µM) were assessed using murine macrophages stimulated with LPS and estimating the levels of pro-inflammatory mediators for 48 h. The in vivo anti-inflammatory activity of TFD was assessed using the carrageenan-induced paw edema test for 6 h. The antinociceptive effects of TFD were evaluated using the formalin test and the acetic acid induced-writhing test. The effects of TFD on locomotor activity were assessed using the open field test and the rotarod test. TFD inhibited the production of TNF-α (IC50 = 5.66 µM) and IL-6 (IC50 = 1.21 µM) in macrophages. TFD (200 mg/kg) showed anti-inflammatory effects with similar activity compared to 10 mg/kg indomethacin. The administration of TFD induced antinociception in the phase 1 (ED50 = 48.2 mg/kg) and the phase 2 (ED50 = 28.9 mg/kg) of the formalin test. In the acetic acid assay, TFD showed antinociceptive effects (ED50 = 32.3 mg/kg) with similar potency compared to naproxen (ED50 = 36.2 mg/kg). In the presence of different inhibitors in the acetic acid assay, only the co-administration of TFD and naloxone reverted the antinociceptive activity shown by TFD alone. TFD did not affect locomotor activity in mice. TFD exerts in vitro and in vivo anti-inflammatory activity and in vivo antinociceptive effects.

Context: A previous study demonstrated that the chloroform extract of Salvia connivens Epling (Lamiaceae) has anti-inflammatory activity. Objective: Identification of the active components in the dicholorometane extract (DESC), and, standardization of the extract based in ursolic acid. Material and methods: DESC was prepared by percolation with dichlromethane and after washed with hot hexane, its composition was determined by CG-MS and NMR, and standardized by HPLC. The anti-inflammatory activity was tested on acute TPA-induced mouse ear oedema at doses of 2.0 mg/ear. The cell viability of macrophages was evaluated by MTT method, and pro- and anti-inflammatory interleukin levels were measured using an ELISA kit. Results: Ursolic acid, oleanolic acid, dihydroursolic acid and eupatorin were identified in DESC, which was standardized based on the ursolic acid concentration (126 mg/g). The anti-inflammatory activities of DESC, the acid mixture, and eupatorin (2 mg/ear) were 60.55, 57.20 and 56.40% inhibition, respectively, on TPA-induced ear oedema. The IC50 of DESC on macrophages was 149.4 μg/mL. DESC (25 μg/mL) significantly reduced TNF-α (2.0-fold), IL-1β (2.2-fold) and IL-6 (2.0-fold) in macrophages stimulated with LPS and increased the production of IL-10 (1.9-fold). Discussion: Inflammation is a basic response to injuries, and macrophages are involved in triggering inflammation. Macrophage cells exhibit a response to LPS, inducing inflammatory mediators, and DESC inhibits the biosynthesis of the pro-inflammatory and promote anti-inflammatory cytokines. Conclusion: DESC has an anti-inflammatory effect; reduced the levels of IL-1β, Il-6 and TNF-α; and increases IL-10 in macrophages stimulated with LPS. Ursolic acid is a good phytochemical marker.

Haemonchus contortus affect small ruminants all over the world. Anthelmintics cause resistance, contamination, and a risk of public health. Prosopis laevigata is a plant used as a home remedy against many diseases in Mexico. This study arose from a preliminary study where a P. laevigata hydroalcoholic extract (Pl-hae) showed anthelmintic activity (aa) against H. contortus. Searching for bioactive compounds (bac) with high aa, the Pl-hae was fractioned obtaining an aqueous (Aq-F) and an ethyl acetate fraction (EtAc-F), and a flavonoid with aa identified as isorhamnetin was obtained from EtAc-F. Both fractions were in vitro assessed by the egg hatch test (eht) and larval mortality (lm) assays. The bac obtained from EtAc-F were characterised by NMR analysis. The highest aa were recorded with EtAc-F, resulting in 100% eht and 80.45% lm at 0.75 and 30 mg/mL, respectively. Alterations in eggs and larvae attributed to isorhamnetin were recorded by environmental scanning electron microscopy, confocal laser scanning and by high-resolution digital-coupled camera. This flavonoid caused 100% eht at 0.07 mg/mL after 48 h and 100% lm at 7.5 mg/mL after 72 h exposure. Isorhamnetin has promising potential as an anthelmintic against sheep haemonchosis.

Interest in anthocyanins has increased remarkably in recent decades, although their wider application has been hampered by instability problems. Thus, this study aimed at developing a strategy to gain access to more stable anthocyanins via enzymatic esterification. For that purpose, three cyanidin derivatives were obtained from underutilized, but easily accessible sources, and their total anthocyanin content was quantified. The purity of cyanidins obtained ranged from 40% to 88% depending on their source. Subsequently, the critical enzymatic reaction conditions were established, and the best results were found using tert-butanol as a solvent, 20 g/L of lipase B from Candida Antarctica, and vinyl cinnamate as acyl donor at ratio 250:1 (acyl donor to anthocyanin). Finally, five new acylated anthocyanin derivatives were synthesized with improved antioxidant activity and thermostability, in comparison to the cyanidin-3-glucoside, which is an advantageous feature for industrial applications.

Preclinical Research Krameria cytisoides is used for the treatment of inflammation, stomach pain, and gastric ulcers. The active ingredient from this plant is a peroxide, kramecyne (KACY) which has anti-inflammatory effects. The aim of the present study was to evaluate the anti-inflammatory activities of KACY in lipopolysaccharide (LPS)-induced systemic chronic inflammation in mice for 60 days, using dexamethasone (DEX) as the positive control, vehicle (the LPS group) as the negative control and the control group (mice without inflammation). KACY did not affect survival, body weight or relative organ weight in mice but it: decreased nitric oxide (NO) production by 68%; prostaglandin E2 (PGE2 ) by 67%; increased release of anti-inflammatory cytokine IL-10 (2.0-fold), and reduced production of the proinflammatory cytokines, IL-6 (2.0-fold), IL-1β (2.4-fold), and TNF-α (2.0-fold). Furthermore, the gastroprotective effects of KACY in mice were evaluated in an ethanol-induced gastric ulcer model. The results showed that KACY at 50 and 100 mg/kg exerted gastroprotective effects with similar activity to 50 mg/kg ranitidine. In gastric tissues, KACY decreased the level of malondialdehyde (MDA) but increased the catalase (CAT) activity. KACY have potential for the treatment of chronic inflammatory diseases due its similar activity to that of DEX. It also has gastroprotective effects.

Aims The aim of this study was to evaluate the antinociceptive (acute assays) and anti-inflammatory (chronic assays) effects of kramecyne (KACY), a peroxide isolated from Krameria cytisoides. Main methods The antinociceptive activity of KACY was evaluated using the hot plate, acetic acid and formalin tests. The effects of KACY on heat-induced hemolysis in rat erythrocytes were also evaluated. The in vivo anti-inflammatory assays were performed using the chronic TPA (12-O-tetradecanoylphorbol 13-acetate) method to induce ear edema and carrageenan-kaolin induced arthritis (CKIA). In the CKIA model, the hot plate test was performed, serum samples were obtained for the quantitation of pro-inflammatory (IL-1β, IL-6, IL-12 and TNF-α) and anti-inflammatory (IL-4 and IL-10) cytokines. Key findings KACY possess antinociceptive effects with comparable activity to naproxen (NPX). KACY inhibited hemolysis (EC50 = 180 μg/mL), in comparison to the untreated group and with a higher potency than NPX (EC50 = 263 μg/mL). KACY at 50 mg/kg decreased inflammation by 38% (chronic TPA-induced edema model) and by 26% (CKIA model), in comparison with the vehicle group and with similar activity to the positive controls 8 mg/kg indomethacin (IND) and 1 mg/kg methotrexate (MTX), respectively. In the CKIA model, KACY increased the release of anti-inflammatory (IL-4 and IL-10) cytokines but reduced the production of pro-inflammatory cytokines (IL-1β, IL-6, IL-12 and TNF-α). KACY at 50 and 100 mg/kg showed antinociceptive effects by 27% and 23%, respectively, in mice with mono-arthritis. Significance KACY might be a good alternative for the treatment of rheumatoid arthritis (RA) due its antinociceptive and anti-inflammatory activities.

New compounds with chemotherapeutic activity are sought after, and plants are an important source of these compounds. Four diterpenes, 19-deoxyicetexone, 7,20-dihydroanastomosine, icetexone and 19-deoxyisoicetexone, were isolated from the hexane-washed chloroform extract of Salvia ballotiflora. The cytotoxic activity of the hexane-washed chloroform extract and its four diterpenes were tested using the MTT assay against three tumor cell lines: HeLa (cervical cancer), A549 (lung cancer) and MCF7 (breast cancer), and two murine cell line: J774A.1 (epithelial cancer) and CT26 (colon cancer), and their IC50 values were determined. 19-Deoxyisoicetexone had the greatest effect on HeLa cells with IC50 of 3.2 μg/ml (9.36 μM), whereas hexane-washed chloroform extract had the best cytotoxic effect on A549 cells with an IC50 of 2.29 μg/ml. These effects of 19-deoxyisoicetexone and hexane-washed chloroform extract were with similar activity compared to cisplatin (IC50 = 1.06 μg/ml in HeLa cells, and 4.6 μg/ml (15.21 μM) in A549 cells). Keywords: Cytotoxicity, 19-Deoxyicetexone, 7,20-Dihydroanastomosine, Icetexone, 19-Deoxyisoicetexone, Cell viability

The indirect vicinal proton-proton coupling constants for pyrrole, furan, thiophene and 15 related heteroaromatic compounds were calculated using the Khon-Sham approximation. An analysis of the four Ramsey contributions to the coupling constants was carried out showing that the Fermi contact term is always positive and dominant, although the remaining contributions have a nonnegligible net negative contribution. The trends observed for the proton-proton coupling constants were rationalized in terms of the properties of the electron density. It was found that electron delocalization between the corresponding hydrogen atoms plays a major role on the observed behavior with the charges of the carbon atoms bonded to them and the accompanying geometric variations being also of importance in the coupling mechanism.

We studied vicinal and long-range coupling constants for 9-anthracene derivatives, e.g., Br, CN, CHO, NO2, CH2Cl, CH2OH, and OCH3. We performed the accurate measurements using modified J doubling in the frequency domain, even for the smallest couplings immersed within the line width. Density functional theory allowed us to reproduce and exhaustively analyze the physical contributions to the values of these spectroscopic parameters. The theory of atoms in molecules defines a delocalization index that correlates linearly with vicinal and long-range coupling constants when they are grouped in terms of the number of bonds between the coupled nuclei. An exception to this behavior is obtained for 4J(H4,H10) values, which have a negative Fermi contact and the largest delocalization index for each molecule. This observation can be explained by a characteristic "gable roof" arrangement formed by the five nuclei involved in the coupling.

Pattern recognition is extremely important for both structure elucidation and stereochemical studies as a means for the measurement of spin-spin coupling constants. Many treatises deal with the formation of splitting trees to create a pattern for a given set of spin-spin coupling constants. We present here a general systematic procedure to easily analyze first order multiplets in NMR spectroscopy. This method has the advantage of measuring coupling constants while deconvolving the signals at the same time using an extension of the modified J doubling in the frequency domain.

In the present work we describe the structure and anti-inflammatory activity of a new compound, kramecyne, isolated from a methanol extract of Krameria cytisoides (Krameriaceae). The structure of kramecyne was determined by IR, NMR, MS, and elemental analysis, which indicated that the structure corresponded to a hexamer of cyclic peroxide monomers. This compound exhibited good anti-inflammatory activity in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema (51.8 ± 6.9% inhibition) and carrageenan-induced rat paw edema models at doses of 50 mg/kg. The compound significantly reduced edema to 63.1% after 1.0 h, and the effect was unchanged for 5 h. Kramecyne did not present acute toxicity, even at doses of 5,000 mg/kg.