In the present work, dried aerial parts of Baccharis ligustrina (Asteraceae) were subjected to microwave assisted extraction (MAE) using aqueous solution of 1-butyl-3-methylimidazolium bromide (BMImBr) and the obtained extract was successively partitioned using hexane and EtOAc. Using reduced amounts of extracts and efficient chromatographic steps, four acyl C6C3 derivatives (n-hexacosyl ferulate, n-hexacosyl, n-octacosyl, and n-triacontyl p-coumarates) were obtained from hexane phase whereas two C6C3 acids (ferulic and p-coumaric) were obtained from EtOAc phase. Isolated phenylpropanoids were evaluated against amastigote forms of parasite Trypanosoma cruzi. As result, it was observed that p-coumaric and ferulic acids were inactives whereas alkyl derivatives displayed EC50 values of 6.5 µmol L-1 (n-octacosyl p-coumarate), 9.3 µmol L-1 (n-triacontyl p-coumarate), 15.7 µmol L-1 (n-hexacosyl p-coumarate), and 32.2 µmol L-1 (n-hexacosyl ferulate). All tested compounds displayed reduced toxicity against NCTC cells (CC50 > 200 mmol L-1).

Electrochemical procedures have emerged as a powerful tool for the synthesis of complex organic molecules including transformation of natural products. In this study, the electrosynthesis of biseugenol in MeOH afforded one new oxidized derivative, which was characterized as methoxyl-oxo-biseugenol (MOB) by nuclear magnetic resonance (NMR) and electrospray ionization-high resolution mass spectrometry (ESI-HRMS) analysis. Since biseugenol was previously described as a cytotoxic natural product, MOB was also tested against tumoral cells B16F10-Nex2 (murine metastatic melanoma) and SKMEL-25 (human metastatic melanoma) as well as against non-tumoral cells MØ Raw 264.7 (murine macrophage immortalized) and HUVEC (human umbilical endothelium). As results, MOB showed inhibitory concentration that affects 50% of cells (IC50) values of 9.5 ± 1.6 mg mL-1(B16F10Nex2), 13.2 ± 2.5 mg mL-1 (SKMEL-25), 19.9 ± 3.5 mg mL-1 (MØ Raw 264.7) and 36.3 ± 7.4 mg mL-1 (HUVEC). Therefore, selectivity index (SI) values of MOB to tumoral cells B16F10Nex2 and SKMEL-25 were calculated as 2.1 and 2.8, respectively, higher than biseugenol (1.4 and 1.7, respectively). Based on these results, the superior cytotoxic activity of MOB in comparison to biseugenol could be associated, at least in part, to the presence of a non-aromatic ring and a conjugated carbonyl system instead of a phenol moiety.

In the present work five acetylene derivatives (1-5), including three unknowns (1, 3 and 4), were isolated from seeds of Porcelia macrocarpa (Annonaceae). The structures of isolated compounds were determined as docos-13-yn-21-enoic acid (1), 3-hydroxy-4-methylene-2-(eicos-11’-yn-19’-enyl)but-2-enolide (2), 3-hydroxy-4-methylene-2-(octadec-9’-yn-17’-enyl)but-2-enolide (3), 3-hydroxy-4-methylene-2-(hexadec-7’-yn-15’-enyl)but-2-enolide (4), and (2S,3R,4R)-3-hydroxy-4-methyl-2-(eicos-11’-yn-19’-enyl)butanolide (5) by analysis of nuclear magnetic resonance (NMR) and electrospray ionization high-resolution mass spectrometry (ESI-HRMS) data. Moreover, all isolated compounds demonstrated selectivity towards intracellular amastigotes of Leishmania (L.) infantum, especially 2-4 with 50% inhibitory concentration (IC50) values of 9.2, 10.4 and 11.0 µM, respectively, indicating superior activity of that determined to positive control miltefosine (IC50 of 17.8 µM). Furthermore, these compounds showed higher selectivity index (SI) in comparison with miltefosine. Since related acetylene fatty acid 1 displayed reduced antiparasitic potential (IC50 of 48.5 µM), the obtained results suggested that the γ-lactone plays an important role in the antileishmanial activity. However, 2-4 exhibited cytotoxicity to mammalian NCTC cells (CC50 ca. 80 µM), which could be a result of the presence of a conjugated carbonyl system in the lactone ring, since 5, the only acetogenin that presents the saturated ring, lacked mammalian cytotoxicity (CC50 > 200 µM).

Although the genus Duguetia is well known for producing alkaloids as chemical constituents, there are no reports of alkaloids identified in the species D. lanceolata. Thus, aiming to identify the chemical composition of this species, the dereplication of alkaloidic phase was performed by use of ultra-high performance liquid chromatography high resolution electrospray ionization tandem mass spectrometry (UHPLC-HR-ESI-MS/MS) and 1H nuclear magnetic resonance (NMR). The chromatographic fractionation of the alkaloid extract from Duguetia lanceolata (Annonaceae) leaves afforded four fractions (I-IV) that were shown to be composed of aporphine alkaloids. 1H NMR analysis and UHPLC-HR-ESI-MS/MS based dereplication allowed the identification of eight alkaloids: glaucine (1), norglaucine (2), isocorydine (3), N-methyllaurotetanine (4), oxoglaucine (5), liriodenine (6), lanuginosine (7), dehydroglaucine (8). Compounds 2,3, 4,6 and 7 were described for the first time in this species, while alkaloids 1,5 and 8 are newly discovered in the genus Duguetia. Additionally, the antiparasitic activity of the four fractions was evaluated in vitro against Leishmania infantum and Trypanosoma cruzi. Fraction I, composed exclusively by 1, displayed activity against Leishmania infantum and Trypanosoma cruzi intracellular amastigotes, with half maximal inhibitory concentration (IC50) values of 7.5 and 28.6 µg mL-1, respectively. Fraction IV (constituted by 2,3 and 4) showed activity against promastigotes of Leishmania infantum with IC50 value of 50.0 µg mL-1, while fraction II (constituted by 5 and 6) showed activity against trypomastigotes of Trypanosoma cruzi, with IC50 values of 83.0 µg mL-1. This work showed that fragmentation in UHPLC-HR-ESI-MS/MS combined with 1H NMR analysis of fractions is useful for identifying alkaloids in mixtures. Additionally, it was also demonstrated the potential of aporphine alkaloids from Duguetia lanceolata St. -Hil (Annonaceae) in the search for new drug candidates for neglected diseases.

Meliaceae representatives are economically important in several aspects including the production of highly prized woods (mahogany, cedar, etc.), constituents for cosmetics, and insecticides. The present study aimed to verify the chemical composition as well as leishmanicidal and cytotoxic potential of essential oils from leaves of two different populations of Guarea macrophylla collected at cities of São Paulo (population I) and Cubatão (population II), São Paulo State, Brazil. Chemically, the oils showed the predominance of sesquiterpenes: cis-β-guaiene, bicyclogermacrene, viridiflorol, and isolongifolan-7α-ol from population I and α-copaene, E-caryophyllene, cis-β-guaiene, and γ-amorphene from population II. In vitro antileishmanial activity against promastigote forms of Leishmania (L.) amazonensis of essential oils was evaluated and displayed 50% effective concentration (EC50) values ranging from 11.8 to 20.5 µg mL-1. Furthermore, toxicity against peritoneal macrophages of BALB/c mice was observed, with 50% cytotoxic concentration (CC50) ranging from 17.7 to > 100 µg mL-1. Multivariate statistical analysis revealed the influence of each constituent of the oils against L. amazonensis being 1,10-di-epi-cubenol, α-amorphene, E-caryophyllene, isopimara-7,15-diene, and β-elemene associated with the antileishmanial potential.

In the present work, leaves of Pentacalia desiderabilis (Asteraceae) were subjected to extraction using aqueous 1-butyl-3-methylimidazolium bromide (BMImBr) in the microwave assisted extraction (MAE). The obtained extract was partitioned using CH2Cl2 and antifungal activity against Cladosporium cladosporioides and C. sphaerospermum of the organic phase was evaluated. Sequentially, this material was subjected to several chromatographic procedures to afford four quinoid derivatives identified as jacaranone (1), methyl-jacaranone (2), quinolacetic acid (3), and methyl 1-hydroxy-4-oxo-cyclohexaneacetate (4), being the first occurrence of compounds 2 - 4 in P. desiderabilis. Isolated quinoid derivatives were submitted to bioautography assay and the obtained results indicated that compounds 1 - 3 are active against Cladosporium cladosporioides (0.78, 12.5 and 12.5 µg, respectively) and C. sphaerospermum (3.13, 12.5 and 12.5 µg, respectively).

Abstract Background: Visceral leishmaniasis is a complex neglected tropical disease caused by Leishmania donovani complex. Its current treatment reveals strong limitations, especially high toxicity. In this context, natural products are important sources of new drug alternatives for VL therapy. Therefore, the antileishmanial and immunomodulatory activity of compounds isolated from Nectandra oppositifolia (Lauraceae) was investigated herein. Methods: The n-hexane extract from twigs of N. oppositifolia were subjected to HPLC/HRESIMS and bioactivity-guided fractionation to afford compounds 1 and 2 which were evaluated in vitro against Leishmania (L.) infantum chagasi and NCTC cells. Results: The n-hexane extract displayed activity against L. (L.) infantum chagasi and afforded isolinderanolide E (1) and secosubamolide A (2), which were effective against L. (L.) infantum chagasi promastigotes, with IC50 values of 57.9 and 24.9 µM, respectively. Compound 2 was effective against amastigotes (IC50 = 10.5 µM) and displayed moderate mammalian cytotoxicity (CC50 = 42 µM). The immunomodulatory studies of compound 2 suggested an anti-inflammatory activity, with suppression of IL-6, IL-10, TNF with lack of nitric oxide. Conclusion: This study showed the antileishmanial activity of compounds 1 and 2 isolated from N. oppositifolia. Furthermore, compound 2 demonstrated an antileishmanial activity towards amastigotes associated to an immunomodulatory effect.

In the present work, dried leaves of Saururus cernuus (Saururaceae) were subjected to extraction using an ionic liquid (1-butyl-3-methylimidazolium bromide - BMImBr) in the microwave assisted extraction (MAE). The obtained extract was partitioned using n-hexane and cytotoxicity activity of this organic phase against murine melanoma cell line (B16F10-Nex2) was evaluated in vitro. Since this extract displayed activity (100% of cell death at 200 µg mL-1) it was subjected to a bioactivity-guided fractionation to afford four related neolignans: threo-austrobailignan-5 (1), threo-austrobailignan-6 (2), threo-dihydroguaiaretic acid (3) and saucernetin (4). Their chemical structures were established based on NMR and MS spectral analysis. Among the isolated neolignans, compound 2 exhibited the highest cytotoxic activity against HeLa (human cervical melanoma) cells with IC50 of 28.3 ± 3.9 µg mL-1 (86 ± 12 µmol L-1). Furthermore, compounds 2 and 3 exhibited the highest cytotoxic activity against A2058 (human melanoma) cells with IC50 of 44.3 ± 4.2 µg mL-1 (135 ± 13 µmol L-1) and 41.5 ± 7.5 µg mL-1 (126 ± 23 µmol L-1), respectively, similar to positive control cisplatin (IC50 = 43.2 ± 3.2 µg mL-1 or 144 ± 11 µmol L-1). Otherwise, compound 4 was inactive (IC50 > 100 µg mL-1 or > 300 µmol L-1). The obtained results provide important data for the selection of bioactive neolignans with promising cytotoxic potential using a simple and fast method employing a green solvent as 1-butyl-3-methylimidazolium bromide (BMImBr).

This work reports the application of an ionic liquid (1-butyl-3-methylimidazolium bromide, BMImBr) in the microwave assisted extraction (MAE) of metabolites from fruits of Schinus terebinthifolius. Dried fruits were individually extracted using BMImBr:H2O 1:1, v/v (experiment 1) and pure H2O (experiment 2) by MAE (10 min at 60 ºC). After partition using EtOAc, the yield to experiment 1 was about 23% while to experiment 2 was 0.1%. The EtOAc fraction obtained from experiment 1 was purified by chromatographic methods to afford 3-oxotirucalla-7,24Z-dien-27-oic acid, 3a-hydroxytirucalla-7,24Z-dien-27-oic acid, 3a-acetoxytirucalla-7,24Z-dien-27-oic acid, gallic acid, and ethyl gallate, being the first occurrence of the third compound as natural product. Cytotoxic activity was evaluated in vitro against cancer cell lines (A2058, HeLa, SiHa, HCT, SKBR-3, U87, and B16F2Nex2), being 3a-acetoxytirucalla-7,24Z-dien-27-oic acid the more active metabolite with IC50 ranging from 10.9 ± 1.3 to 17.3 ± 1.4 µg mL-1, lower than that determined to positive control cisplatin.

Abstract Although the use of exudates in traditional medicine has been commonly observed during ethnopharmacological surveys, few records have been made concerning the scientific merits of these products. The aim of this study was to document ethnopharmacological data and to classify exudates used as medicine by the "caboclos" river-dwellers from the Unini River of Amazonas, Brazil, on chemical analyses basis. Using an ethnographic approach, indicated plants and their respective exudates were collected, identified and incorporated into herbarium of the National Institute of Amazonian Research. To classify these exudates, plant material was extracted using methanol, and obtained extracts were analyzed by Nuclear Magnetic Resonance and mass spectrometry aiming identification of main compounds. Fifteen exudates were indicated by "caboclos" river-dwellers as home remedies; among their therapeutic uses, inflammatory processes, culture-bound syndromes and respiratory diseases are most prominent. Based on their solubility and chemicals classes, fifteen exudates were classified into: latex (7), resins (5), sap (1), gum (1), oleoresin (1); and eleven of them have not been mentioned on pharmacological literature until this moment. The obtained results may contribute to chemical/pharmacological application of exudates from these species, several of which have been classically used in Brazilian folk medicine.

A fração em acetato de etila (EtOAc) obtida a partir da partição do extrato de etanol (EtOH) das folhas de O. sessiliflora R. E. Fries (Annonaceae) foi submetida a diversos procedimentos cromatográficos, incluindo cromatografia líquida de alta eficiência (HPLC), o que resultou no isolamento dos flavonóides: quercetina-3-O-α-L-ramnopiranosil-(1→4)-β-D-glucopiranosídeo (1), inédito na literatura, canferol-3-O-α-L-ramnopiranosil-(1→4)-β-D-glucopiranosídeo (2), rutina (3) e canferol-3-O-rutinosídeo (4). As estruturas foram definidas através da análise dos espectros de ressonância magnética nuclear (NMR) de ¹H e de 13C (1D e 2D) e espectrometria de massas.

The ethyl acetate (EtOAc) phase obtained from the partition of the ethanol (EtOH) extract from leaves of O. sessiliflora R. E. Fries (Annonaceae) was subjected to several chromatographic steps, including high efficiency liquid chromatography (HPLC), to afford the flavonoids: quercetin-3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside (1), unprecedented in the literature, kaempferol-3-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranoside (2), rutin (3), and kaempferol-3-O-rutinoside (4). The structures were elucidated by analysis of their ¹H and 13C nuclear magnetic resonance (NMR) (1D and 2D) spectra and mass spectrometry.

Um novo meroterpeno, 4-[(2'E)-3',7'-dimetilocta-2',6'-dienil]-5-metil-2-(3''-metilbut-2"‑enil)-benzeno-1,3-diol, além de oito substâncias conhecidas, foi isolado do extrato em MeOH das folhas de Peperomia oreophila Hesch. O fenol prenilado foi também isolado como principal componente do extrato em CH2Cl2:MeOH das folhas de Peperomia arifolia Miq. As estruturas das substâncias foram estabelecidas com base em dados espectrais e comparação com dados descritos na literatura

One new meroterpene, 4-[(2'E)-3',7'-dimethylocta-2',6'-dien-1'-yl]-5-methyl-2-(3"‑methylbut-2"-enyl)-benzene-1,3-diol, together with eight known compounds, was isolated from the MeOH extract from the leaves of Peperomia oreophila Hesch. The prenylated phenol was also isolated as main compound from the CH2Cl2:MeOH extract from leaves of Peperomia arifolia Miq. The structures of the substances were established on the basis of the spectral evidences and supported by literature data.

MeOH extract from the leaves of Plectranthus barbatus Andrews (Lamiaceae), showed in vitro anti-trypanosomal activity. The bioassay-guided fractionation resulted in the isolation of a gallic acid derivative, identified as 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), after thorough NMR and MS spectral analysis. Finally, this compound was tested against trypomastigote forms of T. cruzi and displayed an EC50 value of 67 µM, at least 6.6-fold more effective than the standard drug benznidazole. This is the first occurrence of PGG in the Plectranthus genus and the first anti-parasitic activity described for PGG in the literature.

The EtOH extract from leaves of S. terebinthifolius was subjected to partition between EtOH:H2O and hexane, CH2Cl2, and EtOAc. The phases obtained were evaluated in vitro against human tumoral cell lines and the EtOAc phase exhibited activity. Chromatographic procedures afforded gallic acid (1), methyl (2) and ethyl (3) gallates, trans-catechin (4), quercitrin (5), and afzelin (6), being the first occurrence of 1, 4 and 6 in S. terebinthifolius.In vitro cytotoxic evaluation of 1 - 6 indicated that gallic acid (1) displayed higher activity than ethyl gallate (3) against HL-60 and HeLa cells, while compounds 2, 4 - 6 were inactive.

Essential oils of ripe fruits from Schinus terebinthifolius (Anacardiaceae), obtained using a pilot extractor and a Clevenger apparatus were chemically characterized. Due the high amount of (-)- α-pinene in both oils, this monoterpene was tested against the protozoan parasite Trypanosoma cruzi, showing a moderate potential (IC50 63.56 µg/mL) when compared to benznidazole (IC50 43.14 µg/mL). Otherwise, (-)- α-pinene oxide did not showed anti-trypanosomal activity (IC50 > 400 µg/mL) while (-)-pinane showed an IC50 of 56.50 µg/mL. The obtained results indicated that the epoxydation of α-pinene results to the loss of the anti-parasitic activity while its hydrogenation product, contributed slightly to the increased activity.