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The alkaloid Aspidocarpine was isolated from the bark of Aspidosperma desmanthum. Its structure was elucidated by the spectral data of 1H and 13C-NMR (1D and 2D) and high-resolution mass spectrometry (HRESIMS). The antihypertensive activity was investigated by intravenous infusion in Wistar rats. This alkaloid significantly reduced (p < 0.05) the systolic, median, and diastolic blood pressures of rodents, without causing motor incoordination and imbalance in the rotarod test. The results indicate that the alkaloid Aspidocarpine exerts its antihypertensive activity without causing sedation or the impairment of motor functions.

Mandevilla Lindl. is an important genus of the Apocynaceae family, not only as ornamental plants but also for its medicinal uses. In Brazil, Mandevilla species are indicated to treat asthma and skin infections, their anti-inflammatory potential and wound healing properties are also reported in the literature. Concerning their chemical composition, this group of plants is a conspicuous producer of pregnane glycosides. Mandevilla dardanoi is an endemic species from the Brazilian semiarid region not studied by any phytochemical methods. In view of the medicinal potential of Mandevilla species, this study aimed to isolate new pregnane glycosides from M. dardanoi . To achieve this main goal, modern chromatography techniques were employed. Five new pregnane glycosides, dardanols A-E, were isolated from the roots of M. dardanoi by HPLC. Their structures were determined using extensive 1D and 2D-NMR and mass spectrometry (MS n and HRESIMS) data. The cytotoxicity and the anti-inflammatory potential of these compounds were evaluated. The first was evaluated by measuring proinflammatory cytokines and nitric oxide production by stimulated macrophages. Dardanols were able to inhibit the production of nitric oxide and reduce IL-1β and TNF-α. The current work demonstrates the chemodiversity of Brazilian semiarid species and contributes to amplifying knowledge about the biological potential of the Mandevilla genus.

Plants have historically been a rich source of successful anticancer drugs and chemotherapeutic agents, with research indicating that this trend will continue. In this contribution, we performed high-throughput cytotoxicity screening of 702 extracts from 95 plant species, representing 40 families of the Brazilian Cerrado biome. Activity was investigated against the following cancer cell lines: colon (Colo205 and Km12), renal (A498 and U031), liver (HEP3B and SKHEP), and osteosarcoma (MG63 and MG63.3). Dose-response tests were conducted with 44 of the most active extracts, with 22 demonstrating IC 50 values ranging from <1.3 to 20 µg/mL. A molecular networking strategy was formulated using the Global Natural Product Social Molecular Networking (GNPS) platform to visualize, analyze, and annotate the compounds present in 17 extracts active against NCI-60 cell lines. Significant cytotoxic activity was found for Salacia crassifolia , Salacia elliptica , Simarouba versicolor , Diospyros hispida , Schinus terebinthifolia , Casearia sylvestris var. lingua , Magonia pubescens , and Rapanea guianensis . Molecular networking resulted in the annotation of 27 compounds. This strategy provided an initial overview of a complex and diverse natural product data set, yielded a large amount of chemical information, identified patterns and known compounds, and assisted in defining priorities for further studies.

The genus Cedrela P. Browne, which belongs to the Meliaceae family, has eighteen species. Trees of this genus are of economic interest due to wood quality, as well as being the focus of studies because of relevant biologic activities as in other Meliaceae species. These activities are mainly related to limonoids, a characteristic class of compounds in this family. Therefore, the aim of this review is to perform a survey of the citations in the literature on the Cedrela genus species. Articles were found on quantitative and qualitative phytochemical studies of the Cedrela species, revealing the chemical compounds identified, such as aliphatics acid and alcohol, flavonoids, tocopherol, monoterpenes, sesquiterpenes, triterpenes, cycloartanes, steroids, and limonoids. Although some activities were tested, the majority of studies focused on the insecticidal, antifeedant, or insect growth inhibitor activities of this genus. Nonetheless, the most promising activities were related to their antimalarial and antitripanocidal effects, although further investigations are still needed.

Zornia brasiliensis Vogel (Leguminosae) is a species popularly known in Brazil as "urinária", "urinana", and "carrapicho", it is popularly used as a diuretic and in the treatment of venereal diseases. A specific methodology to obtain a saponin-enriched fraction and high-performance liquid chromatography coupled with diode array detection, ion trap mass spectrometry, and TOF-MS (HPLC-DAD-ESI-MS/MS) was applied for the analysis of triterpene saponins. The MS and MS/MS experiments were carried out by ionization in negative mode. Molecular mass and fragmentation data were used to support the structural characterization of the saponins. Based on retention times, high-resolution mass determination and fragmentation, 35 oleanane-triterpene saponins were tentatively identified in Z. brasiliensis .

A phytochemical study of leaves and twigs of Psychotria nuda resulted in 19 compounds, including five indole alkaloids, N , N , N -trimethyltryptamine, lyaloside, strictosamide, strictosidine, and 5α-carboxystrictosidine; two flavonolignans, cinchonain Ia and cinchonain Ib; an iridoid, roseoside; a sugar, lawsofructose; a coumarin, scopoletin; a diterpene, phytol; three triterpenes, pomolic acid, spinosic acid, and rotungenic acid; and five steroids, sitosterol, stigmasterol, campesterol, β -sitosterol-3- O - β -d-glucoside, and β -stigmasterol-3- O - β -d-glucoside. Some compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis and their ability to inhibit NO production by macrophages stimulated by lipopolysaccharide (LPS). The compounds pomolic acid, spinosic acid, strictosidine, and 5α-carboxystrictosidine displayed antimycobacterial activity with minimum inhibitory concentrations ranging from 7.1 to 19.2 µg/mL. These compounds showed promising inhibitory activity against NO production (IC 50 3.22 to 25.5 μg/mL). 5 α-carboxystrictosidine did not show cytotoxicity against macrophages RAW264.7 up to a concentration of 100 µg/mL. With the exception of strictosamide, this is the first report of the occurrence of these substances in P. nuda .

The new pentacyclic triterpene 11 β -hydroxypristimerin ( 1 ), along with the known metabolites pristimerin ( 2 ), 6-oxopristimerol ( 3 ) and vitideasin ( 4 ), were isolated from a Salacia crassifolia root wood extract, following a bioassay-guided fractionation approach. Both the extract and the purified triterpenes displayed pronounced cytotoxic activity against human cancer cell lines. The NCI-60 cell line screen revealed that compound 2 was the most active, with a mean GI 50 of 0.17 μM, while compound 1 had a mean GI 50 of 8.7 μM. A COMPARE analysis of the screening results showed that pristimerin is likely to be the main compound responsible for the cytotoxic activity of the extract (mean GI 50 of 0.3 μg·mL −1 ). A targeted search for pristimerin and related derivatives using LC-MS/MS revealed the presence of pristimerin ( 2 ) and 6-oxopristimerol ( 3 ) in all Celastraceae species examined and in all plant parts tested, while vitideasin ( 4 ) was only detected in the genus Salacia .

Two new triterpenes cycloartane-type, named 24-methylencycloartan-12-oxo-3β,22α-diol and trichiliol, were isolated from the leaves of Trichilia casaretti C. DC. together with three known triterpenes—24-methylencycloart-3β,22-diol, 22,25-dihydrocycloart-23( E )-en-3β-ol, and 22( R )-hydroxycycloart-24-en-3-ol. These compounds were characterized on the basis of their spectral data, mainly 1D (¹H and 13 C) and 2D NMR (¹H-¹H-COSY, ¹H-¹H-NOESY, HMQC, HSQC, and HMBC), and mass spectra (EI-MS and HR-ESI-MS), also involving comparison with data from the literature.

This study identified two phenolic compounds in Schinus terebinthifolius Raddi fruits: naringenin (first report in this species) and gallic acid. Their structures were elucidated by nuclear magnetic resonance (NMR) data (¹H-, 13 C-NMR) and a high-performance liquid chromatography (HPLC) technique. A high content of phenolics (659.21 mg of gallic acid equivalents/g of sample-Folin-Ciocalteau method) and total flavonoids (140.69 mg of rutin equivalents/g of sample-aluminum chloride method) were quantified in S. terebinthifolius , as well as high antioxidant activity (77.47%-2,2-diphenyl-1-picrylhydrazyl, DPPH method). The antihypertensive activity related to its phenolic content was investigated. After intravenous infusion in Wistar rats, these phenolics significantly reduced ( p < 0.05) the systolic, median, and diastolic arterial pressures of individuals. The rotarod test was performed to determine the mechanism of action of the sample vasorelaxant effect. It was found that its action exceeded that of the positive control used (diazepam). This confirmed the vasodilatory activity exerted by S. terebinthifolius fruits is related to the phenolic compounds present in the plant, which are potent antioxidants and inhibit oxidative stress, mainly in the central nervous system., Competing Interests: The authors declare no conflict of interest.

Four new compounds were isolated from the branches of Piper montealegreanum Yuncker, a shrub found in the Amazon rainforest, including two new dihydrochalcones named claricine ( 1 ) and maisine ( 2 ), a cinnamic acid derivative 3 and a phenylalkanoid 4 , along with a porphyrin identified as the known compound phaeophytin a ( 5 ). The structures were established using spectroscopic experiments, including 1D and 2D NMR and HRESIMS experiments, performed on the two monoterpene dihydrochalcones and their monoacetyl derivatives. The structural diversity of these substances is very important for the Piper genus chemotaxonomy., Competing Interests: The authors declare no conflict of interest.

The genus Psychotria (Rubiaceae) comprises more than 2000 species, mainly found in tropical and subtropical forests. Several studies have been conducted concerning their chemical compositions, showing that this genus is a potential source of alkaloids. At least 70 indole alkaloids have been identified from this genus so far. This review aimed to compile 13 C-NMR data of alkaloids isolated from the genus Psychotria as well as describe the main spectral features of different skeletons.

Lichens are a form of symbiont between a fungus and an alga or cyanobacterium, which contains a wide variety of organic compounds with certain secondary metabolite classes typical of these organisms. The Ramalina genus has approximately 246 species distributed around the World, of which in this review approximately 118 species with published chemical or biological activity studies of extracts or isolated compounds were cited. From the 153 mentioned compounds, only 27 passed were tested for biological activity, being usnic acid the most studied compound and the one showing the best results in almost all in vitro tests performed, although other compounds also presented excellent results as antimicrobial, antitumor and anti-inflammatory agents, among others. Extracts of several species also presented significant results in performed biological tests, demonstrating the potential that these organisms have, in particular, the gender Ramalina, to produce bioactive molecules that can be used as a model for the production of pharmaceuticals.

Agave sisalana (sisal) is known worldwide as a source of hard fibers, and Brazil is the largest producer of sisal. Nonetheless, the process of removing the fibers of the sisal leaf generates 95% waste. In this study, we applied chemical sequential steps (hydrothermal extraction, precipitation, liquid-liquid extraction, crystallization, SiO2 and Sephadex LH 20 column chromatography) to obtain pectin, mannitol, succinic acid, kaempferol and a mixture of saponins as raw chemicals from sisal biomass. The structural identification of these compounds was performed though spectrometric methods, such as Infrared (IR), Ultraviolet (UV), Mass spectrometry (MS) and Nuclear magnetic resonance (NMR). All the sisal chemicals found in this work are used by both the chemical and pharmaceutical industries as excipients or active principles in products.

A new natural product, a 3,9-(1,2,3-trioxocine)-type steroid, named rauianodoxy (6), was isolated from Rauia nodosa, together with five steroids: sistostenone (1), stigmastenone (2), sitosterol (3), stigmasterol (4) and ergosterol peroxide (5), one coumarin, O-geranylosthenol (7), and three alkaloids, N-methylflindersine (8), zantobungeanine (9) and veprissine (10). Compounds 5-8 were isolated for the first time in the genus Rauia. These compounds were characterized on the basis of their spectral data, mainly one and two-dimensional NMR, and mass spectra, also involving comparison with the literature data. Theoretical studies at the DFT level reveal structural parameters for the 1,2,3-trioxole bridge compatible with known structures containing a similar group.

Ursolic acid, an important bioactive compound, was isolated from ethanol extract of aerial parts of Sambucus australis. In order to develop bioactive ursolic acid derivatives, two semi-synthetic compounds were obtained through modification at C-3. The antibacterial activity of the ursolic acid and its derivatives was investigated. The microdilution method was used for determination of the minimal inhibitory concentration (MIC), against twelve bacterial strains. The influence of ursolic acid and its derivatives on the susceptibility of some bacterial pathogens to the aminoglycosides antibiotics neomycin, amikacin, kanamycin and gentamicin was evaluated. The most representative synergistic effect was observed by 3β-formyloxy-urs-12-en-28-oic acid at the concentration of 64 μg/mL in combination with kanamycin against Escherichia coli (27), a multidrug-resistant clinical isolate from sputum, with reduction of MIC value from 128 μg/mL to 8 μg/mL. Ursolic acid and its derivatives were examined for their radical scavenger activity using the DPPH assay, and showed significant activity.

Two novel protolimonoids, named lepidotrichilins A (1) and B (2), four known protolimonoids, 21,23-epoxy-7α-21α-dihydroxyapotirucalla-14,24-dien-3-one (3), 21,23-epoxy-7α-21β-dihydroxyapotiru-calla-14,24-dien-3-one (4), dysorone D (5), deoxy-flindissone (6), and the two steroids β-sitosterol (7) and stigmasterol (8) were identified in leaves of Trichilia lepidota subsp. schumanniana (Harms) T.D. Pennington. From wood the coumarin scopoletin (9) was isolated. The structures were established by NMR (1D (1)H and (13)C-NMR and 2D (1)H-(1)H COSY, HMQC and HMBC), mass spectroscopy and infrared (IR) spectral data. The hexane and methanol extracts of the leaves, the protolimonoids lepidotrichilins A (1) and B (2) (IC₅₀ 42.7 µg mL(-1)) and the protolimonoid deoxy-flindissone (6; IC₅₀ 9.3 µgmL(-1)) exhibited significant cytotoxic activity against the MOLT-4 and U937 leukemic cell lines.

One novel triterpene cycloartane-type, named hirtinone (1), six protolimonoids - nilocitin (2), dihydronilocitin B (3), melianone epimers (4) and (5), piscidinol A (6) and melianone lactone (7), one tertranortriterpenoid, hirtin (8), and one sesquiterpene, spathulenol (9), were identified in the fruits of Trichilia hirta. The structures were established by 1D and 2D NMR (1H and 13C-NMR, DEPTQ, 1H-1H-COSY, 1H-1H-NOESY, HSQC and HMBC), high resolution mass spectroscopy (HR-ESI-MS) and infrared (IR) spectral data.

The zoanthids Palythoa caribaeorum and Protopalythoa variabilis are among the most abundant marine species along the Brazilian coast. We now report the isolation and structure elucidation of two unprecedented sulfonylated ceramides, palyosulfonoceramide A (1) and palyosulfonoceramide B (2) from specimens collected off Brazil's northeastern coast. The structures of 1 and 2 were established using a combination of NMR analyses, including: evaluation of 1H, 13C, ¹H--¹H COSY, ¹H--¹³C HSQC, ¹H--¹³C HMBC, and ¹H--¹⁵N HMBC NMR spectra, high-resolution mass spectrometry and chemical degradation. In addition, we also isolated the corresponding known ceramides, N-((2S,3R,4E,8E)-1, 3-dihydroxyoctadeca-4,8-dien-2-yl)-hexadecanamide (3) and N-((2S,3R,4E)-1,3-dihydroxy octadeca-4-en-2-yl)-hexadecanamide (4), which provided further support for the assignments of 1 and 2.

Indole alkaloids are the chemotaxonomic markers of the Aspidosperma genera. Those that have the simplest plumeran skeleton are classified as the precursors of biosynthetic routes and the intermediates for several synthetic reactions. This work aims to review the ¹H and ¹³C-NMR data, up to 2011, describing the skeleton of 35 different plumeran indole alkaloids, from a group of 46 of them, and highlight the main spectral differences amongst them.

This work reviews the production of terpenoids by endophytic fungi and their biological activities, in period of 2006 to 2010. Sixty five sesquiterpenes, 45 diterpenes, five meroterpenes and 12 other terpenes, amounting to 127 terpenoids were isolated from endophytic fungi.

The methanolic extract of Tabernaemontana catharinensis (Apocynaceae) roots, which contains alkaloids with several biological activities, was separated on a preparative scale using high-speed counter-current chromatography. The optimum solvent system was found to be a mixture of CHCl(3)-MeOH-H(2)O [5:10:6 (v/v/v)] and led to a successful separation of two monoterpenic indole alkaloids, voachalotine (1) and 12-methoxy-N(b)-methylvoachalotine (2) in approximately 4.0 hours. The alkaloids were all isolated at purities over 95%, and their structures were established on the basis of spectroscopic methods, including 1D and 2D NMR and EI/MS.