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Pharmaceutical heparins from different manufacturers may present heterogeneities due to particular extraction and purification procedures or even variations in the raw material manipulation. Heparins obtained from different tissues also differ in their structure and activity. Nevertheless, there is an increased demand for more accurate assessments to ensure the similarities of pharmaceutical heparins. We propose an approach to accurately assess the similarity of these pharmaceutical preparations based on well-defined criteria, which are verified with a variety of refined analytical methods. We evaluate six commercial batches from two different manufacturers which were formulated with Brazilian or Chinese active pharmaceutical ingredients. Biochemical and spectroscopic methods and analysis based on digestion with heparinases were employed to evaluate the purity and structure of the heparins. Specific assays were employed to evaluate the biological activity. We observed minor but significant differences between the constitutive units of the heparins from these two manufacturers, such as the content of N-acetylated α-glucosamine. They also have minor differences in their molecular masses. These physicochemical differences have no impact on the anticoagulant activity but can indicate particularities on their manufacturing processes. The protocol we propose here for analyzing the similarity of unfractionated heparins is analogous to those successfully employed to compare low-molecular-weight heparins.

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The occurrence of racemic and enantiomerically enriched (scalemic) mixtures of secondary metabolites in their natural sources is a rare phenomenon. The unprecedent case of enantiomeric variations from levorotatory to dextrorotatory, and back to levorotatory, passing through an almost racemic mixture, was recently documented for areolal, the major epoxythymol of Piptothrix areolare. In an attempt to shed some light to understand the reasons for such an unusual behavior, herein, we evaluated this phenomenon by correlating the areolal enantiomeric purity with several environmental variables, including temperature, humidity, rain precipitation, wind speed, and radiation during over 1 year of the plant life cycle. The specific rotation and enantiomeric excess determined by 1 H-NMR-BINOL measurements provided the scalemic variations of areolal samples isolated from the roots collected from the same location along a 427-day period. The 1 H-NMR-BINOL methodology provided better sensitivity to enantiomeric variations than specific rotation measurements. Statistical data, including matrix correlation analysis, exploratory analysis by heatmap plotting, and the principal component analysis (PCA), suggested direct correlation of the scalemic variation with humidity, rain precipitation, and radiation variables with the best PCA explanation (78.4%) and noncritical or poor correlations in PCA explained in 60.2% and 48.4%, respectively. When variations in the optical activity parameter of any metabolite are observed, the search for scalemic mixtures along their host plant life cycle should be undertaken. Herein, this phenomenon could be associated with interactions with soil microorganisms and with evolutionary aspects of Piptothrix areolare which belongs to Asteraceae, one of the most successfully adaptable plant families.

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Search for safe antioxidants and novel nutraceuticals urged to evaluate the antioxidant, anti-acetylcholine esterase and anti-lipoxygenase activity of various leaf extracts of Conocarpus lancifolius. Extraction was optimized from freeze dried plant extracts quenched with liquid nitrogen using water, ethanol, methanol, hexane, ethyl acetate and chloroform. Maximum extract yield, total phenolic contents and total flavonoid contents were obtained in case of ethanolic extraction. The highest 2,2-diphenyl-1-picrylhydrazylradical scavenging in terms of IC50 value of 55.26 µg/mL was observed for ethanolic leaf extract. The acetylcholine esterase and lipoxygenase inhibitory activities (IC50) were also observed for ethanolic extract. These findings for ethanolic extract were statistically significant when compared with other extracts (ρ<0.05). The haemolytic % values indicated that all extracts were associated with very low or negligible toxicity. The epicatechin, isorhamnetin, rutin, scopoleptin, skimmianine, quercetin-3-O-α-rhamnoside, quercetin-3-O-ß-glucoside, cornoside, creatinine, choline, pyruvic acid, α-hydroxybutyric acid, phyllanthin and hypophyllanthin were identified as major functional metabolites in ethanolic leaf extract of C. lancifoliusby 1H-NMR. The identified metabolites were probably responsible for the pharmacological properties of C.lancifolius. The findings may be utilized as pharmacological leads for drug development and food fortification.

Se insta a la búsqueda de antioxidantes seguros y nuevos nutracéuticos para evaluar la actividad antioxidante, anti-acetilcolina esterasa y anti-lipoxigenasa de varios extractos de hojas de Conocarpus lancifolius. La extracción se optimizó a partir de extractos de plantas liofilizados enfriados con nitrógeno líquido usando agua, etanol, metanol, hexano, acetato de etilo y cloroformo. En el caso de extracción etanólica se obtuvo el rendimiento máximo de extracto, el contenido de fenoles totales y el contenido de flavonoides totales. La mayor eliminación de radicales 2,2-difenil-1-picrilhidrazilo en términos de valor de CI50 de 55,26 µg/mL se observó para el extracto de hoja etanólico. También se observaron las actividades inhibidoras de la acetilcolina esterasa y lipoxigenasa (CI50) para el extracto etanólico. Estos hallazgos para el extracto etanólico fueron estadísticamente significativos en comparación con otros extractos (ρ<0.05). Los valores del % hemolítico indicaron que todos los extractos estaban asociados con una toxicidad muy baja o insignificante. Se identificaron la epicatequina, isorhamnetina, rutina, escopoleptina, skimmianina, quercetina-3-O-α-ramnosido, quercetina-3-O-ß-glucósido, cornosido, creatinina, colina, ácido pirúvico, ácido α-hidroxibutírico, filantrina e hipofillantina. como metabolitos funcionales principales en el extracto etanólico de hojas de C. lancifoliuspor 1H-NMR. Los metabolitos identificados probablemente fueron responsables de las propiedades farmacológicas de C. lancifolius. Los hallazgos pueden utilizarse como pistas farmacológicas para el desarrollo de fármacos y la fortificación de alimentos.

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In this work, the new diaminochromenes: 2,5-dimono-8-methoxychromeno[4,3,2-de][1,6]naphthyridine-4-carbonitrile (4), 8-ethoxy-2-imino-3,4-dihydro-2H-chromene-3-carbonitrile-4-malononitrile (5), 2,5-diamino-8-ethoxychromene[4,3,2-de][1,6]naphthyridine-4-carbonotrile (6), were synthesized and fully characterized through 600 MHz using 1H, 13C, APT, gHSQC, gHMBC, ROESY-1D and gated decoupling 13C. Further docking studies suggested that these compounds are capable of intercalating with the Drew-Dickerson Dodecamer DNA and, therefore, be candidates to work as effective compounds to decrease the cancer radiotherapy.Communicated by Ramaswamy H. Sarma.

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Pressurized hot water extraction (PHWE), known as a "green" extraction technique, was used to obtain polysaccharide from the pulp of gabiroba (Campomanesia xanthocarpa Berg) fruits. The effects of pressure, temperature, and flow rate on pectin yields were analyzed through a full factorial design experiment 23. The optimal extraction conditions to achieve maximum pectin yield (5.70 wt%) were pressure of 150 bar, temperature of 120 °C, and flow rate of 1.5 mL min-1. The high pressure (100 bar) promoted an increase in galacturonic acid content (36.0%) compared to conventional hot water extraction (CEGP) with 25.7%. Differences in the proportion of homogalacturonan (HG) and rhamnogalacturonan (RG-I) domains ranging from 16.3 to 35.4% and 61.7 to 80.1%, respectively, were observed for each pectin sample according to the extraction conditions. The mono-dimensional (13C-NMR) and bi-dimensional (1H/13C HSQC-NMR) analyses confirmed the presence of HG and RG-I regions and indicated the presence of arabinogalactans type I (AG-I) and arabinogalactans type II (AG-II) in the PHWE pectin samples, which was not found for pectins from gabiroba pulp obtained by CEGP. The results showed that PHWE proved to be a promising method for extracting pectins from gabiroba fruits.

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A new source of pectin with a cytotoxic effect on glioblastoma cells is presented. A homogeneous GWP-FP-S fraction (Mw of 29,170 g mol-1) was obtained by fractionating the crude pectin extract (GW) from Campomanesia xanthocarpa pulp. According to the monosaccharide composition, the GWP-FP-S was composed of galacturonic acid (58.8%), arabinose (28.5%), galactose (11.3%) and rhamnose (1.1%), comprising 57.7% of homogalacturonans (HG) and 42.0% of type I rhamnogalacturonans (RG-I). These structures were characterized by chromatographic and spectroscopic methods; GW and GWP-FP-S fractions were evaluated by MTT and crystal violet assays for their cytotoxic effects. Both fractions induced cytotoxicity (15.55-37.65%) with concomitant increase in the cellular ROS levels in human glioblastoma cells at 25-400 µg mL-1, after 48 h of treatment, whereas no cytotoxicity was observed for normal NIH 3T3 cells. This is the first report of in vitro bioactivity and the first investigation of the antitumor potential of gabiroba pectins.

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The pulp of gabiroba fruits was submitted to a hot water extraction, giving rise to a crude pectin named GW. GW was shown to be composed mainly of arabinose (54.5%), galacturonic acid (33.5%), galactose (7.6%), and rhamnose (1.6%). GW was characterized by chromatographic and spectroscopic methods indicating the presence of homogalacturonans (HG) with a degree of methyl-esterification (DM) of 60% and rhamnogalacturonans I (RG-I). HG domain represents 31.9% and RG-I domain 65.3%. Furthermore, GW was submitted to sequential fractionation methods, giving rise to GWP-TEP fraction, structurally characterized by the predominance of HG regions, and confirmed by NMR analysis. The rheological behavior of GW was analyzed at 1%, 3%, and 5% (w/v) concentration with 0.1 mol L-1 NaCl. All samples showed shear thinning behavior. In the oscillatory measurements, the 1% GW showed a liquid-like behavior, while the 3% presented a concentrated solution behavior and the 5% GW a gel behavior.

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The 750 MHz 1H NMR spectrum of cholesteryl benzoate (1b) could be assigned completely, which means all chemical shifts and all coupling constants, including some long-range values, were established. This task was possible by extracting many approximate coupling constant values in the overlapped spectrum region from an HSQC experiment, and using these values in the 1H iterative full spin analysis integrated in the PERCH NMR software. The task was facilitated using our published data for 3ß-acetoxypregna-5,16-dien-20-one (3), the assignment data of the sesquiterpene benzoquinone dihydroperezone (2), also performed in the present study, which contains the same carbon atoms chain than cholesterol (1a), and an HSQC study of (25R)-27-deuteriocholesterol (1c) we prepared some 40 years ago. The HSQC values of 1c in combination with the coupling constants of 1b also allowed to completely assigning the spectrum of 1c. The complete assignment of 1b and 1c further provided the opportunity to estimate the hydrogen shifts induced upon benzoylation of cholesterol. Comparison of the experimental vicinal coupling constants of 1b with the values calculated using the Altona software provides an excellent correlation. In addition, a single crystal X-ray diffraction study of 1b provided the molecular conformation in the solid state, which revealed the side chain adopts an extended conformation.

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In this study, we isolated and structurally characterized, for the first time, a galactoglucomannan (GGM) from the pulp of gabiroba, a Myrtaceae family species. The HPSEC-MALLS-RI analysis showed a homogeneous polysaccharide with molar mass of 25,340gmol-1. The monosaccharide composition showed that the GGM consisted of Man:Glc:Gal in a molar ratio of 1:1:0.6. Methylation and 1D and 2D NMR analyses suggested that the main chain of the GGM consisted of ß-d-Glcp and ß-d-Manp units (1→4)-linked. The α-d-Galp substitutions occur mainly at O-6 position of ß-d-Manp units. The glycosidic linkages of the GGM were evident by the presence of the characteristic signals of 4-O-substituted residues at δ 78.6/3.69 for both ß-d-Glcp and ß-d-Manp. Furthermore, the O-6 substitutions for both ß-d-Glcp and ß-d-Manp units were confirmed by signals at δ 67.1/4.00 and 3.93. The interglycosidic correlations, obtained through the analysis of the HMBC spectrum, further confirm the structure.

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Complete and unambiguous 1 H NMR chemical shift assignment of α-cedrene (2) and cedrol (9), as well as for α-pipitzol (1), isocedrol (10), and the six related compounds 3-8 has been established by iterative full spin analysis using the PERCH NMR software (PERCH Solutions Ltd., Kuopio, Finland). The total sets of coupling constants are described and correlated with the conformational equilibria of the five-membered ring of 1-10, which were calculated using the complete basis set method. Copyright © 2015 John Wiley & Sons, Ltd.

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Compounds containing the tricyclic dibenzo[b,e]azepine system have potential activity in the treatment of a number of diseases. Continuing with our studies on the synthesis of new small and potentially bioactive molecules, a synthetic route, involving acid-catalysed intramolecular Friedel-Crafts cyclization, to the readily separable diastereoisomers of 11-ethyl-6,11-dihydro-5H-dibenzo[b,e]azepine-6-carboxamide, a potentially useful precursor in the synthesis of analogues of some anti-allergenic, antidepressant and antihistaminic drugs currently in use, has been developed starting from 2-allylphenylamine and methyl 2-bromo-2-phenylacetate and proceeding via racemic methyl 2-[(2-allylphenyl)amino]-2-phenylacetate (A) and racemic 2-[(2-allylphenyl)amino]-2-phenylacetamide (B), to give the two diastereoisomers (I) and (II), C17H18N2O. Isomers (I) and (II), and their precursors (A) and (B), have all been fully characterized spectroscopically. Structure analysis of the minor isomer (I) shows that it has the (6RS,11RS) configuration, and that the azepine ring adopts a conformation intermediate between the boat and twist-boat forms, with the carboxamide and ethyl substituents both occupying quasi-equatorial sites. The molecules of (I) are linked by a combination of N-H...O, N-H...π(arene) and C-H...π(arene) hydrogen bonds to form complex sheets. Comparisons are made with the structures of some related compounds.

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The Amazon forest is rich in plant species diversity, among them,Piranhea trifoliata stands out, which is popularly known as piranheira, because their fruits are eaten by fish. Their barks are used as bath composition on uterus inflammation and as tea in malaria treatment. This study aimed to fractionate the dichloromethane and dichloromethane phase from methanolic extract of leaves of Piranhea trifoliata. The leaves were dried, grounded and extracted with dichloromethane, methanol and water. The methanol extract was partitioned with dichloromethane and ethyl acetate. The chromatographic fractionation yielded six pentacyclic triterpenoids: friedelan-3-one, 28-hydroxy-friedelan-3-one, 30-hydroxy-friedelan-3-one, lupeol, alfa- and beta-amyrin mixture, besides the mixture of the steroids: beta-sitosterol and stigmasterol. The substances structures were identified by 1H- and13C-Nuclear Magnetic Resonance (NMR) analysis and literature data comparison. This is the first report describing the chemical study of P. trifoliata leaves.

A floresta Amazônica é rica em diversas espécies vegetais, dentre elas, destaca-se Piranhea trifoliata, a qual é conhecida popularmente como piranheira, por seus frutos servirem de alimentos para peixes. Suas cascas são utilizadas como curativo para inflamação no útero em banhos de assento e para chás no tratamento de malária. O objetivo deste trabalho foi o fracionamento cromatográfico do extrato diclorometânico e da fase diclorometânica do extrato metanólico das folhas de Piranhea trifoliata. As folhas foram secas, moídas e extraídas com diclorometano, metanol e água. O extrato metanólico foi submetido à partição com diclorometano e acetato de etila. O fracionamento cromatográfico conduziu ao isolamento de seis triterpenoides pentacíclicos: friedelan-3-ona, 28-hidroxi-friedelan-3-ona, 30-hidroxi-friedelan-3-ona, lupeol, mistura de alfa- e beta-amirina, além da mistura dos esteroides beta-sitosterol e estigmasterol. As estruturas das substâncias foram identificadas pela análise dos espectros de Ressonância Magnética Nuclear (RMN) de 1H e de 13C e comparações com dados da literatura. Este é o primeiro relato descrevendo o estudo químico das folhas de P. trifoliata.

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The Amazon forest is rich in plant species diversity, among them,Piranhea trifoliata stands out, which is popularly known as piranheira, because their fruits are eaten by fish. Their barks are used as bath composition on uterus inflammation and as tea in malaria treatment. This study aimed to fractionate the dichloromethane and dichloromethane phase from methanolic extract of leaves of Piranhea trifoliata. The leaves were dried, grounded and extracted with dichloromethane, methanol and water. The methanol extract was partitioned with dichloromethane and ethyl acetate. The chromatographic fractionation yielded six pentacyclic triterpenoids: friedelan-3-one, 28-hydroxy-friedelan-3-one, 30-hydroxy-friedelan-3-one, lupeol, alfa- and beta-amyrin mixture, besides the mixture of the steroids: beta-sitosterol and stigmasterol. The substances structures were identified by 1H- and13C-Nuclear Magnetic Resonance (NMR) analysis and literature data comparison. This is the first report describing the chemical study of P. trifoliata leaves.(AU)

A floresta Amazônica é rica em diversas espécies vegetais, dentre elas, destaca-se Piranhea trifoliata, a qual é conhecida popularmente como piranheira, por seus frutos servirem de alimentos para peixes. Suas cascas são utilizadas como curativo para inflamação no útero em banhos de assento e para chás no tratamento de malária. O objetivo deste trabalho foi o fracionamento cromatográfico do extrato diclorometânico e da fase diclorometânica do extrato metanólico das folhas de Piranhea trifoliata. As folhas foram secas, moídas e extraídas com diclorometano, metanol e água. O extrato metanólico foi submetido à partição com diclorometano e acetato de etila. O fracionamento cromatográfico conduziu ao isolamento de seis triterpenoides pentacíclicos: friedelan-3-ona, 28-hidroxi-friedelan-3-ona, 30-hidroxi-friedelan-3-ona, lupeol, mistura de alfa- e beta-amirina, além da mistura dos esteroides beta-sitosterol e estigmasterol. As estruturas das substâncias foram identificadas pela análise dos espectros de Ressonância Magnética Nuclear (RMN) de 1H e de 13C e comparações com dados da literatura. Este é o primeiro relato descrevendo o estudo químico das folhas de P. trifoliata.(AU)

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This work describes the total and unambiguous assignment of the 750 MHz (1)H NMR spectrum of 3ß-acetoxypregna-5,16-dien-20-one or 16-DPA (1), the well-known intermediate utilized in the synthesis of biological important commercial steroids. The task was accomplished by extracting the coupling constant values in the overlapped spectrum region by HSQC, and using these values in the (1)H iterative full spin analysis integrated in the PERCH NMR software. Comparison of the experimental vicinal coupling constants of 1 with the values calculated using Altona provides an excellent correlation. The same procedure, when applied to the published data of progesterone (2) and testosterone (3), afforded an acceptable correlation for 2 and a poor correlation for 3. In the last case, this suggested the reassignment of all four vicinal coupling constants for the methylene signals at the C-15 and C-16 positions, demonstrating the utility of this methodology.

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Fucosylated chondroitin sulfate (FCS) is a glycosaminoglycan found in sea cucumbers. It has a backbone like that of mammalian chondroitin sulfate (4-ß-d-GlcA-1→3-ß-d-GalNAc-1)n but substituted at the 3rd position of the ß-d-glururonic acid residues with α-fucose branches. The structure of these branches varies among FCSs extracted from different species of sea cucumbers, as revealed by solution NMR spectroscopy. Some species (Isostichopus badionotus and Patalus mollis) contain branches formed by single α-fucose residues but with variable sulfation patterns (2,4-, 3,4- and 4-sulfation). FCS from Ludwigothurea grisea is distinguished because it contains preponderant branches formed by disaccharide units containing non-sulfated and 3-sulfated α-fucose units at the reducing and non-reducing ends, respectively. Despite the structural variability on their α-fucose branches, these FCSs have similar anticoagulant action on assays using purified reagents. They have serpin-dependent and serpin-independent effects. Pharmacological assays using experimental animals showed that the three types of FCSs have similar antithrombotic effect and bleeding tendency. They also activate factor XII on the same range of concentration. Based on these observations, we proposed that only few sulfated α-fucose branches along the FCS chain are enough to assure the binding of this glycosaminoglycan to proteins of the coagulation system. Substitution with additional sulfated α-fucose does not increase further the activity. Overall, the use of FCSs with marked variability on their branches of α-fucose allowed us to establish correlations between structures vs biological effects of these glycosaminoglycans on a more refined basis. It opens new avenues for therapeutic intervention using FCSs.

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Chemical investigation of the aerial parts of Senecio polypodioides lead to the isolation of the new eudesmanoid 1ß-angeloyloxyeudesm-7-ene-4ß,9α-diol (1) and the known dirhamnosyl flavonoid lespidin (3), while from roots, the known 7ß-angeloyloxy-1-methylene-8α-pyrrolizidine (5) and sarracine N-oxide (6), as well as the new neosarracine N-oxide (8), were obtained. The structure of 1 and 8 was elucidated by spectral means. Complete assignments of the (1)H NMR data for 5, 6, sarracine (7), and 8 were made using one-dimensional and two-dimensional NMR experiments and by application of the iterative full spin analysis of the PERCH NMR software.

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