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Introduction: Trypanosoma cruzi is the agent of Chagas’ disease and affects approximately 6-8 million people worldwide. The search for new anti-T. cruzi drugs are relevant because only two drugs exist actually. The objective of this study was to investigate the effect of the extracts from the seeds of Lonchocarpus cultratus on T. cruzi, its cytotoxicity as well as to elucidate its chemical profile. Methodology: The characterization of the extracts was done using 1H-RMN. T. cruzi forms were treated with increasing concentrations of the extracts and after, the percentage of inhibition and IC50 or LC50 were calculated. Murine peritoneal macrophages were treated with different concentrations of the extracts to evaluate the cellular viability. The hemotoxicity was accessed by verifying the levels of hemolysis caused by the extracts on human red blood cells. Results: Chalcones isocordoin and lonchocarpin were detected in the dichloromethane extract, and chalcone lonchocarpin was detected in the hexane extract. The dichloromethane extract showed higher activity against all the forms of T. cruzi compared to the other two extracts, but the hexane showed the best selectivity index. The cytotoxicity observed in murine macrophages was confirmed in human erythrocytes, with dichloromethane extract having the highest toxicity. The methanolic extract showed the lowest anti-T. cruzi activity but was nontoxic to peritoneal murine macrophages and red blood cells. Conclusions: L. cultratus extracts have the potential to be explored for the development of new anti-trypanosomal drugs. This study was the first to demonstrate the action of extracts from the genus Lonchocarpus on infecting forms of T. cruzi.

Trypanosoma cruzi is the agent of Chagas disease, an infection that affects around 8 million people worldwide. The search for new anti-T. cruzi drugs are relevant, mainly because the treatment of this disease is limited to two drugs. The objective of this study was to investigate the trypanocidal and cytotoxic activity and elucidate the chemical profile of extracts from the roots of the Lonchocarpus cultratus. Roots from L. cultratus were submitted to successive extractions with hexane, dichloromethane, and methanol, resulting in LCH, LCD, and LCM extracts, respectively. Characterization of extracts was done using 1H-RMN, 13C-RMN, CC and TLC. Treatment of T. cruzi forms (epimastigotes, trypomastigotes, and amastigotes) with crescent concentrations of LCH, LCD, and LCM was done for 72, 48, and 48 h, respectively. After this, the percentage of inhibition and IC50/LC50 were calculated. Benznidazole was used as a positive control. Murine macrophages were treated with different concentrations of both extracts for 48 h, and after, the cellular viability was determined by the MTT method and CC50 was calculated. The chalcones derricin and lonchocarpine were identified in the hexane extract, and for the first time in the genus Lonchocarpus, the presence of a dihydrolonchocarpine derivative was observed. Other chalcones such as isocordoin and erioschalcone B were detected in the dichloromethane extract. The dichloromethane extract showed higher activity against all tested forms of T. cruzi than the other two extracts, with IC50 values of 10.98, 2.42, and 0.83 µg/mL, respectively; these values are very close to those of benznidazole. Although the dichloromethane extract presented a cytotoxic effect against mammalian cells, it showed selectivity against amastigotes. The methanolic extract showed the lowest anti-T. cruzi activity but was non-toxic to peritoneal murine macrophages. Thus, the genus Lonchocarpus had demonstrated in the past action against epimastigotes forms of T. cruzi but is the first time that the activity against infective forms is showed, which leading to further studies with in vivo tests.

A especie Aeschynomene sensitiva e considerada uma erva daninha que ocorre principalmente em regioes de clima tropical alagavel, e pode ser encontrada em varios estados brasileiros. Ate o presente momento nao ha relatos na literatura sobre estudo quimico e farmacologico para essa especie. O primeiro estudo fitoquimico de sementes, folhas e galhos de Aeschynomene sensitiva levou ao isolamento do rotenoide glicosilado 6’-hidroxi-6a, 12a-dehidrorotenone, do isoflavonoide glicosilado 2’,7 dihidroxi-4’,5’dimetoxiisoflavona, dos flavonoides quercetina 3-O-β-D-glicosideo, quercetina 3-O-β-D-galactopiranosideo e quercetina-3-O-α-L-ramnopiranosideo, dos compostos fenolicos acido galico e galato de metila e da saponina soiasaponina I.. As estruturas dos compostos isolados foram atribuidas com base em dados espectroscopicos de RMN uni- e bidimensionais e comparacao com dados da literatura. Foram avaliadas as atividades anti-inflamatoria, antitumoral e antioxidantes do extrato metanolico bruto e suas fracoes. As fracoes acetato de etila das sementes (FAcS) e folhas (FAcF) apresentaram elevada atividade antioxidante com IC50 12,4 and 18,2 µg/mL, respectivamente.

New pectin derivative (Pec-MA) was obtained in specific reaction conditions. The presence of maleoyl groups in Pec-MA structure was confirmed by 1H NMR and FTIR spectroscopy. The substitution degree of Pec-MA (DS=24%) was determined by 1H NMR. The properties of Pec-MA were investigated through WAXS, TGA/DTG, SEM and zeta potential techniques. The Pec-MA presented amorphous characteristics and higher-thermal stability compared to raw pectin (Pec). In addition, considerable morphological differences between Pec-MA and Pec were observed by SEM. The cytotoxic effect on the Caco-2 cells showed that the Pec-MA significantly inhibited the growth of colon cancer cells whereas the Pec-MA does not show any cytotoxic effect on the VERO healthy cells. This result opens new perspectives for the manufacture of biomaterials based on Pec with anti-tumor properties.

International audience; As part of our continuing chemical and biological analyses of Rubiaceae species from Cerrado, we isolated novel alkaloids 1 and 2, along with known compounds epicatechin, ursolic acid, and oleanolic acid, from Galianthe ramosa. Alkaloid 2 inhibited malate synthase from the pathogenic fungus Paracoccidioides spp. This enzyme is considered an important molecular target because it is not found in humans. Molecular docking simulations were used to describe the interactions between the alkaloids and malate synthase.

The phytochemical study of Oncidium baueri (Orchidaceae) afforded two new compounds (1 and 2), along with thirteen known structures (3–15). The chemical structures were established on the basis of spectral evidence and the new compounds, obtained as a mixture of two glycosylated flavanones were assigned by comprehensive spectroscopic analysis by 1D and 2D NMR spectroscopy and HRMS. Moreover, the cytotoxic activity of the crude extract (EBOB), semi-purified fractions (HEOB, CLOB, ACOB, BUOB and HMOB) and some isolated metabolites against ten human cancer cell lines (U251, UACC-62, MCF-7, NCI-ADR/RES, 786-0, NCI-H460, PC-3, OVCAR-3, HT29, K562) and the antiprotozoal activity against Trypanosoma cruzi and Leishmania amazonensis were evaluated. The CLOB fraction showed the best antitrypanosomal and antileishmanial activities, as well as considerable cytotoxicity against cancer cell lines UACC-62 (melanoma) and K562 (leukemia) with GI50 values of 6.83 μg/mL and 0.5 μg/mL, respectively. Furthermore, BUOB and HMOB fractions showed selectivity for UACC-62 (melanoma) with GI50

Twelve methallylic derivatives were studied using 13C NMR spectroscopy and theoretical calculations. Theoretical coupling constants were obtained with SOPPA (CCSD). All atoms were described by the EPR-III basis set, except for halogens, which were represented by the cc-pVTZ basis set. Geometries were optimized at the MP2/aug-cc-pVTZ level of theory, confirming previous results that the gauche and s-cis conformers predominate. Experimental nJCH coupling constants were determined from coupled 13C NMR spectra, while the 1JCC couplings were measured through the INADEQUATE technique. The experimental and theoretical values were in good agreement. Correlations with the usual substituent physicochemical parameters indicated that the 1 J C 3 H c values (where Hc is attached to the C3 carbon bearing the substituent) exhibit good correlations with Taft’s sigma (σI inductive parameter) and the Swain–Lupton Field Effect (F) (R ∼ 0.957), while other correlations were not similarly significant (R values

Objectives To synthesize and characterize different molar weight urethane multimethacrylates with a single stage (one-pot) procedure. To prepare and characterize the properties of related composites. Methods Two methacrylate precursors were initially synthesized. Then, these precursors and the multimethacrylate system formed by their coupling were characterized by FTIR and 1 H NMR. The final product was used as a matrix (with TEGDMA and SiO 2 silanized microparticles) in the preparation of composites and their physical and mechanical properties were compared to those of a bis-GMA-based resin. Water sorption and solubility measurements of the composites were also performed. Results FTIR and NMR suggested that the proposed synthesis route yields a mixture of mainly urethane-di, -tri, and tetramethacrylates. The composites presented low polymerization shrinkage ( e.g. 1.88 ± 0.08% for a resin with 70% of SiO 2 ) and high flexural strength ( e.g. 124.74 ± 9.68 MPa for a resin with 65% of SiO 2 ) when compared to the bis-GMA based resin and other composites found to date. Water sorption and solubility results show that the composites were deemed compliant with ISO 4049 requirements. Significance The mixture containing different molar weight of urethane multimethacrylates showed to be an excellent substitute for bis-GMA, achieving an equilibrium of properties (unlike reports elsewhere which show the enhancement of some parameters in detriment to others) and composites with low polymerization shrinkage, suitable microhardness and degree of conversion, and up to standard water sorption/solubility and flexural strength.

Arctium lappa L. (Asteraceae) is used in folk medicine around the World, and shows several kinds of biological activity, particularly in vitro antitumor activity in different cell lines. This study evaluated the antiproliferative activity of the crude extract, semipurified fractions, and isolated compounds from the leaves of A. lappa, through bioassay-guided testing in Caco-2 cells. The crude extract was obtained with a 50% hydroethanolic extract and then partitioned with hexane, ethyl acetate, and n-butanol. The ethyl-acetate fraction (EAF) showed antiproliferative activity. This fraction was subjected to sequential column chromatography over silica gel to afford onopordopicrin (1), mixtures of 1 with dehydromelitensin-8-(4'-hydroxymethacrylate) (2), a mixture of 2 with dehydromelitensin (3), mixture of 1 with melitensin (4), dehydrovomifoliol (5), and loliolide (6). The compounds were identified by spectroscopic methods (NMR, MS) and comparison with literature data. This is the first description of compounds 2-5 from this species. The compounds tested in Caco-2 cells showed the following CC(50) (µg/mL) values: 1: 19.7 ± 3.4, 1 with 2: 24.6 ± 1.5, 2 with 3: 27 ± 11.7, 1 with 4: 42 ± 13.1, 6 30 ± 6.2; compound 5 showed no activity.

The infrared spectra of 3-X-2-methylpropenes (X = Cl, Br, I, NMe(2), NEt(2), OH, OMe, OEt, SH, SMe and SEt) have been recorded at room temperature in CCl(4) solution. The C=C stretching mode was analyzed and compared to theoretically calculated data to give insight about the conformational isomerism of these compounds. A combination band systematically appears in all spectra (except for amines); the remaining ν(C=C) band and the corresponding intensities were used to obtain the conformer populations. For second-period atoms bonded to C-3, two or more conformers are observed in CCl(4) solution, but when substitution by heavier atoms takes place, only one conformer is observed under the tested conditions, i.e., the gauche form with respect to the C=C-C-X dihedral angle. Therefore, steric hindrance between X and =CH(2) in the s-cis form is strongly dependent on the heteroatom size, while the effect of the alkyl chain bonded to the heteroatom seems to be of secondary importance.

Chitosan and N,N,N-trimethyl chitosan (TMC) were treated with heparin (HP) to produce polyelectrolyte complexes (PECs). The structures of PECs were characterized by Fourier transform infrared and CP-MAS 13C NMR spectroscopies. A thermal stability of TMC/HP complex was evaluated by thermogravimetric analyses, and morphology was investigated by SEM images. The ratio between the carbons bonded to noncharged nitrogen atoms (CΦ) and the carbons bonded to positively charged nitrogen atoms (Cω) in TMC was calculated through of the degree quaternization (DQ), being the DQ obtained through 1H NMR data. Experiments of controlled release of HP were performed in distilled water at pH ∼7, using methylene blue/heparin system as solute. The release profiles of HP from TMC/HP complex are quite different each other. The value of CΦ/Cω ratio was used for explaining such an effect. The CΦ/Cω ratio tends to be constantly (∼0.69) as high as the pH of medium in which the PEC of TMC/HP was obtained. The change of CΦ/Cω ratio on the pH was also considered to explain the improvement of thermal stability of PEC2 with increase of pH. Data show that PEC of TMC/HP formed at pH 8 is a promising material for uses in oral site-specific HP release systems.

Two new quaternary alkaloids, compound 1 and the 14-oxo derivative 2 , were isolated along with the known alkaloid strictosamide ( 3 ) from the leaves of Psychotria prunifolia (Kunth) Steyerm. (Rubiaceae, Psychotriae). Their structures were elucidated using spectroscopic methods (1D and 2D NMR, IR, and HRMS).

The photoelectron (PE) spectra of some 3-monosubstituted 2-methylpropenes H 2 C C(CH 3 )CH 2 X [X = Cl, Br, I, OH, OMe, OEt, SH, SMe, SEt, N(Me) 2 and N(Et) 2 ] have been recorded. A preliminary analysis is presented indicating some trends in the ionization potentials associated with application of OVGF method and NBO analysis from MP2/6-31G(d,p) and cc-pVDZ level of theory indicating that the more effective hyperconjugation effect leads to the most stable conformers. The sensitivity of the outermost ionization energies of selected molecules with respect to the level of theory was analyzed. Application of the CASPT2 method with ANO basis set and geometries from MP2 calculations provided results in excellent agreement with the experimental data.

Two new abietane-type diterpenes, 3beta-hydroxy-9alpha, 13alpha-epidioxyabiet-8(14)-ene (1) and 3-oxo-9alpha,13alpha-epidioxyabiet-8(14)-ene (2), were isolated from the methanolic crude extract of the petioles of Sagittaria montevidensis ssp montevidensis (Alismataceae). The structures of 1 and 2 were determined on the basis of spectrometric analyses including HREIMS, IR as well as ¹H and 13C 1 and 2D NMR.

Certain members of the genus Eugenia are used as foods. One of these species is Eugenia umbelliflora, which is used for its fruits. The aim of the study was to isolate the constituents of the CH2Cl2 fraction obtained from E. umbelliflora O. Berg (Myrtaceae) and also to evaluate its antimicrobial properties. Two new meroterpenoids, eugenial C (3) and eugenial D (4) were isolated from the unripe fruits of E. umbelliflora and their structures established mainly by extensive NMR spectroscopy. In previous studies, the CH2Cl2 extract showed significant antibacterial activity, which can be attributed to meroterpenoids isolated in this study. The compounds eugenials C and D exhibited potent activity against Bacillus subtilis and Staphylococcus aureus and different strains of MRSA and activity similar to those of the antibiotics used in antimicrobial therapies.

The isolation and structure determination of new cyclic peptide alkaloid ixorine, along with five known constituents frangulanine, syringaresinol, cinnamtannin B-1, daucosterol and mannitol from the branches of Ixora brevifolia are described. The cyclic peptide frangulanine is being described for the first time in the Rubiaceae family. The structures were elucidated on their spectral data basis, mainly one- (1H, 13C, DEPT) and two-dimensional (COSY, NOESY, HSQC and HMBC) nuclear magnetic resonance (NMR) and by comparison with data from the literature. The mixture of two cyclopeptide alkaloids showed weak activity against Leishmania amazonensis.

The conformational behaviour of the some methallyl compounds (H2CC(CH3)CH2X; XF, Cl, Br, I, OH, OMe, OEt, SH, SMe, SEt, NMe2 and NEt2) has been investigated through MP2 and B3LYP levels of theory using the 6-31G(d,p) and/or 6-311+G(d,p) basis sets. For certain set of compounds the 3-21G and CEP-31G basis set were used. The calculations indicate the existence of s-cis and gauche conformers, considering the CC–C–X dihedral angle, and the skew and trans forms with respect to the C–C–X–R dihedral angle. Good agreement is obtained among the relative energies calculated at different levels of theory, except for the oxygen derivatives, and with respect to experimental data from the literature for some compounds. Similar conformational behavior is observed among the analogous methallyl, allyl and propanones derivatives.

A B S T R A C T One new veratroyl derivative, together with the known iridoids barlerin and shanzhiside methyl ester were isolated from Molopanthera paniculata. The structures of compounds were established by 1D and 2D NMR and HRMS analyses.

Axial-equatorial conformational proportions for cyclohexyl-N,N-dimethyl carbamate have been measured, for the first time, by the Eliel method, ¹H and 13C dynamic nuclear magnetic resonance (DNMR). The results were compared against those determined by theoretical calculations. By the Eliel method at least five experimentally independent measureables were used in CCl4, CDCl3 and CD3CN. The ¹H and 13C low temperature experiments were performed in CF2Br2/CD2Cl2 . Semiempirical methods MNDO, AM1 and PM3 and ab initio molecular orbital calculations at the HF/STO-3G and HF/6-31G(d,p) levels have been performed on the axial and equatorial conformers populations. All applied methods correctly predict the equatorial conformer preference over the axial one. The resulting equatorial preferences determined by NMR data and theoretical calculations are in good agreement. As proporções dos confôrmeros axial-equatorial do N,N-dimetilcarbamato de cicloexila foram determinadas, pela primeira vez, pelo método de Eliel, pela ressonância magnética nuclear dinâmica(rmnd) de ¹H e de 13C e foram comparados com resultados obtidos através de cálculos teóricos. Pelo método de Eliel foram utilizados pelo menos cinco parâmetros experimentais independentes, em CCl4, CDCl3 e CD3CN. Os experimentos de ¹H e de 13C a baixas temperaturas foram realizados em CF2Br2/CD2Cl2. Os métodos semiempíricos MNDO, AM1 e PM3 e cálculos ab initio de orbital molecular nos níveis HF/STO-3G e HF/6-31G(d,p) também foram utilizados. Tanto os métodos que utilizaram a RMN como os cálculos teóricos corretamente indicaram a preferência do confôrmero equatorial em relação ao axial e os valores obtidos pelos diferentes métodos demonstraram boa concordância.

The influence of solvent on the miscibility of poly(methyl methacrylate)/poly(vinyl acetate), PMMA/PVAc, and the interpolymer interactions responsible for their miscibility were investigated. 2D nuclear overhauser effect spectroscopy, NOESY, experiments were performed with pure polymers and also with 50/50 blend. Under conditions of blend miscibility, chloroform at 40°C and toluene at 30°C, NOESY results indicated the presence of two different types of intermolecular interactions between (i) methoxy protons of PMMA and methyne protons of PVAc; (ii) methoxy protons of PMMA and methyl protons of PVAc. In immiscible conditions, in DMF and in benzene, both at 40°C, only type (ii) interactions were detected. These results indicate that intermolecular interactions between the methoxy protons of PMMA and the methyne protons of PVAc are responsible for the miscibility of the blends in chloroform and toluene. The interactions between the methoxy protons of PMMA and the methyl protons of PVAc do not contribute to the miscibility of the blend and were explained as originating from contacts of unlike polymers in the interphase.

Leaves and branches of Machaerium hirtum Vell. (Fabaceae), native to South America, were subjected to phytopharmacological investigation in order to identify its major chemical constituents and evaluate its extracts, fractions and isolated compounds in assays for anti-inflammatory activities. These were performed using mouse ear edema model, pleurisy and myeloperoxidase activity assays. Six compounds were isolated and identified as the flavanones swertisin and isovitexin, the alkaloid 4-hydroxy-N-methylproline, the triterpenes friedelin and lupeol, and the steroids sitosterol and stigmasterol. These compounds were identified by nuclear magnetic resonance of (1)H and (13)C data, in comparison with literature.

This phytochemical investigation of Guettarda pohliana leaves led to the isolation of the triterpenes pomolic acid, rotundic acid, 3β,6α,19α,23-tetrahydroxyurs-12-en-28-oic acid, clethric acid, ursolic acid and oleanolic acid, the monoterpenoids loliolide and secoxyloganin, besides daucosterol and steroids. The structures of the isolated compounds were assigned on the basis of NMR data, including two-dimensional NMR methods. The anti-inflammatory activity of the crude methanolic extracts from leaves and roots, as well as of their fractions, was evaluated.

Phytochemical investigation of Aeschynomene fluminensis leaves and branches led to isolation of the flavonoid glycosides kaempferol 3,7-di-O-α-L-rhamnopyranoside, kaempferol 7-O-α-L-rhamnopyranoside, kaempferol 3-O-apiofuranosil-7-O- rhamnopyranoside, quercitin 3-O-α-L-rhamnopyranoside, quercitin 3-O-arabinofuranoside, 8-β-D-glucopyranosyl 4',5,7-trihydroxyflavanone, the isoflavonoid 4',7-di-hydroxy-isoflavone, the dimer epicatechin-(2β→7, 4β→8)- epicatechin, the polyol 3-O-methyl-chiro-inositol and two steroids in sitosterol and stigmasterol mixture. These compounds were identified by NMR ¹H and 13C and compared with literature data. Anti-inflammatory activity of the crude methanolic extract and its fractions was evaluated.

From the aerial parts of Bouchea fluminensis , a new iridoid glucoside, named boucheoside, along with four known iridoid glucosides, lamiide, lamiidoside, durantoside II, and duranterectoside C, were isolated. The structure of the new compound was elucidated based on the spectroscopic evidence.

A new tetrahydro β-carboline alkaloid that has an oligosaccharide unit was isolated from the root extracts of the Palicourea coriacea . The structure was elucidated using spectral methods, including 2D NMR: COSY, HMQC, HMBC and NOESY.

There are NMR data of 1H and 13C of the iridoid plumieride, but controversy related to the assignments of the protons H-3 or H-10 and carbons C-6 or C-7 and C-3 or C-10 are described in the literature. There are a little discussion regarding to the resonance assignment of protons of the glycoside unity. Analysis based on 2D shift correlated NMR spectra (COSY, HETCOR, HETCORLR) and NOE difference 1H NMR spectra allowed to assign unambigously the chemical shift of 1H and 13C of plumieride which has been found in the literature with non coincident values.