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Maytenus quadrangulata is a species endemic to the Atlantic Forest in Brazil. While the pharmacological potential of the Maytenus genus is well-documented, specific phytochemical studies on M. quadrangulata remain limited, although previous investigations have identified triterpenes with significant cytotoxic effects. In this study, five new acetylated triterpenoid derivatives, namely, friedelane-3α,29-diyl diacetate (1), friedelane-3α,11β-diyl diacetate (2), friedelane-3α,25-diyl diacetate (3), 3β-hydroxyfriedelane-24-yl acetate (4), and 11β-hydroxyfriedelane-3α-yl acetate (5), were obtained by acetylation of a triterpenoid mixture from the chloroform extract of M. quadrangulata leaves. Additionally, 12 known compounds were identified from this extract. The structural elucidation was performed using spectroscopic (IR, NMR) and spectrometric (MS) techniques. The cytotoxic activity of the isolated triterpenes was assessed on leukemia (K-562, THP-1), breast cancer (MDA-MB-231), and epithelial lung carcinoma (A549) cell lines. Among the tested compounds, compound 5 showed a more pronounced effect against the K-562 chronic myeloid leukemia cell line . Furthermore, all tested compounds exhibited moderate cytotoxic activity against the A549 epithelial lung carcinoma cell line. The antiviral potential of the isolated compounds was also evaluated against Zika virus (ZIKV), along with the activity against phytopathogenic fungi Alternaria alternata, Botrytis cinerea, and Fusarium oxysporum; however, no significant inhibitory effects were observed. Collectively, this study provides a detailed characterization of the bioactive triterpenoids from M. quadrangulata, reinforcing its relevance as a potential source of cytotoxic natural products.

The PhI(OAc) ₂ ‐oxidation of the triterpene lupeol by manganese porphyrin was achieved, leading to 94% of lupeol conversion. Conditions aligned with principles of green chemistry, including the use of ethyl acetate as a solvent and iodobenzene diacetate as an oxidant, were studied. This approach led to the production of eight products from lupeol, notably achieving transformations at the C20 olefin moiety; six lupeol's products were isolated whereas the other two had their structures proposed supported on basic chemical tests (e.g., Fehling's test) and well‑established reactivity patterns in organic chemistry. These modifications were performed without the typical preceding protection of the C3 hydroxyl of lupeol, simplifying the synthetic route. Besides, the isopropenyl group of lupeol was converted to carboxylic acids through one‐pot oxidation. This study reinforces the promising use of manganese porphyrins as catalysts for the oxidative transformation of other natural products of biological interest.

Maytenus quadrangulata occurs naturally in the Brazilian biomes Caatinga and Atlantic Forest, and previous studies have demonstrated its potential as a source of bioactive molecules. In light of this, a phytochemical study of the chloroform extract of Maytenus quadrangulata branches was carried out, yielding the new triterpene 30-oxo-2,3-seco-lup-20(29)-ene-2,3-dioic acid (1) and a mixture containing the new semisynthetic triterpene 25-hydroxy-7-oxofriedelan-3α-yl acetate (2). In addition, seven known compounds were also obtained: friedelan-3-one (3), friedelan-3β-ol (4), friedelan-3α-ol (5), a mixture of long-chain fatty acids of β-sitosterol and lupeol-β-sitosterol alkanoate (6) and lupeol alkanoate (7), friedelane-3,7-dione (8) and 2,3-seco-lup-20(29)-ene-2,3-dioic acid (9). Structural elucidation of the isolated metabolites was performed using ¹H and ¹³C nuclear magnetic resonance (NMR). The chemical structures of the new compounds, 1 and 2, were confirmed by the analysis of two-dimensional NMR spectra (HSQC, HMBC, COSY, and NOESY). An in vitro cytotoxicity assay against the THP-1 and K-562 leukemia cell lines and an in silico analysis using ADMETLab 3.0 were performed for compounds 1 and 9. The novel triterpene (1) exhibited the highest cytotoxicity and the most favorable drug-like profile, underscoring its potential as an anticancer therapeutic.

Species of the genus Monteverdia, among them, M. quadrangulata, have been traditionally used in Brazil to treat infections and inflammation. The objective of this study was to investigate the effect of polar extracts of Monteverdia quadrangulata on viral particles and the replication cycle of Zika virus (ZIKV). The anti-ZIKV effect of ethyl acetate extracts from leaves (LAE) and branches (TAE) of M. quadrangulata was investigated in vitro, and the median effective concentration (EC50), selectivity index (SI) and mechanisms of action (virucidal activity and antiviral activity in the adsorption, internalization and post-infection stages) were evaluated. The EC50 values of the LAE and TAE extracts were ≤ 50µg/mL. LAE was the most selective (EC50 = 29 ± 9µg/mL, SI = 31) with significant virucidal activity. LAE also reduced viral load by 4 log units at different times after infection. Probable catechins and epicatechins, previously identified as constituents of LAE, act synergistically at different stages of the viral cycle, inactivating extracellular ZIKV and interfering in the viral replication cycle.

Salacia grandifolia is naturally found in the Atlantic Forest regions of Brazil. Despite the pharmacological potential of plants from the Salacia genus, phytochemical studies on this species have not been reported in literature. A new triterpene, 28-hydroxyfriedelane-3,15-dione (1), and seven known compounds (friedelan-3-one (2), friedelan-3β-ol (3), friedelane-3,15-dione (4), 15α-hydroxyfriedelan-3-one (5), 28-hydroxyfriedelan-3-one (6), 30-hydroxyfriedelan-3-one (7), and 29-hydroxyfriedelan-3-one (8)) were obtained from the hexane extract of Salacia grandifolia leaves. These isolated compounds and three extracts, hexane (EH), chloroform (EC), and ethyl acetate (EAE), were assessed for their potential biological activities, which consisted in the evaluation of antiviral activity against a murine coronavirus, mouse hepatitis virus 3 (MHV-3), antibacterial activity against the susceptible and methicillin-resistant Staphylococcus aureus (MRSA), and antileukemia activity against the THP-1 and K-562 cell lines. The extracts EH and EAE along with the triterpenes 1 and 6 exhibited moderate to high antiviral activity, with emphasis on 6, which presented an EC₅₀ value of 2.9 ± 0.3 μM. None of the compounds presented antibacterial activity against the tested strains. The evaluated compounds 1, 4, 6 and 7 exhibited low cytotoxic activity against the tested leukemia cell lines. Taken together, this study comprises an overview for the potential of the Salacia grandifolia biological activities, including a new isolated triterpene.

Pristimerin exhibits significant potential as a therapeutic agent, demonstrating activity against various human cancer cells. The assumption is that the trimer of pristimerin enhances the strength and selectivity of pristimerin-DNA interactions through a multivalent effect. Therefore, to synthesize the trimer of pristimerin, a multi-step route was adopted. The initial step involved the synthesis of 2-(2-(2-azidoetoxy)ethoxy)ethan-1-ol (R1) through an SN2 reaction, with a yield of 52%. The compound N-(tert-butoxyl-carbonyl)-tris-(hydroxymethyl)aminomethane (R2), with the amino group protected by tert-butoxyl carbamate, was obtained with an 87% yield and, the trialkyne, N-(tert-butoxyl-carbonyl)-tris-(propargyl)-methyl)aminomethane (R3), was obtained with a 43% yield. Despite successful synthesis of compound R1, R2 and R3, various methodologies were attempted for the transesterification between pristimerin and R1 to produce 2-(2-(2-azidoethoxy)ethoxyethyl pristimerinoate (R4), including chemical and enzymatic hydrolysis of pristimerin as an alternative route. However, none of these attempts succeeded, indicating the remarkable resistance of carbon C-29 in pristimerin to these reactions. DOI:https://doi.org/10.56238/sevened2024.003-056 Pristimerina apresenta um potencial significativo como agente terapêutico, destacando-se pela sua atividade contra diversas células cancerosas humanas. Supõe-se que o trímero da pristimerina potencialize a força e a seletividade das interações entre a pristimerina e o DNA, por meio de um efeito multivalente. Diante disso, para sintetizar o trímero da pristimerina, foi planejado uma rota sintética com várias etapas. A primeira etapa, envolveu a obtenção do produto 2-(2-(2-azidoetoxi)etoxi)etan-1-ol (R1), via reação SN2, com rendimento de 53%. O composto N-(terc-butoxil-carbonil)-tris-(hidroximetil)aminometano (R2), com o grupo amino protegido com terc-butoxil carbamato foi obtido com rendimento de 87% e o trialcino, N-(terc-butoxil-carbonil)-tris-(propargil)metil)aminometano (R3), com rendimento de 43%. Apesar do êxito nas sínteses dos compostos R1, R2 e R3, foram empregadas diversas metodologias na transesterificação entre a pristimerina e R1 para obtenção do produto pristimerinoato de 2-(2-(2-azidoetoxi)etoxi (R4), incluindo a hidrólise química e enzimática da pristimerina como uma rota alternativa. No entanto, nenhuma das tentativas obteve sucesso, evidenciando a notável resistência do carbono C-29 da pristimerina a essas reações. DOI:https://doi.org/10.56238/sevened2024.003-056

Pristimerin exhibits significant potential as a therapeutic agent, demonstrating activity against various human cancer cells. The assumption is that the trimer of pristimerin enhances the strength and selectivity of pristimerin-DNA interactions through a multivalent effect. Therefore, to synthesize the trimer of pristimerin, a multi-step route was adopted. The initial step involved the synthesis of 2-(2-(2-azidoetoxy)ethoxy)ethan-1-ol (R1) through an SN2 reaction, with a yield of 52%. The compound N-(tert-butoxyl-carbonyl)-tris-(hydroxymethyl)aminomethane (R2), with the amino group protected by tert-butoxyl carbamate, was obtained with an 87% yield and, the trialkyne, N-(tert-butoxyl-carbonyl)-tris-(propargyl)-methyl)aminomethane (R3), was obtained with a 43% yield. Despite successful synthesis of compound R1, R2 and R3, various methodologies were attempted for the transesterification between pristimerin and R1 to produce 2-(2-(2-azidoethoxy)ethoxyethyl pristimerinoate (R4), including chemical and enzymatic hydrolysis of pristimerin as an alternative route. However, none of these attempts succeeded, indicating the remarkable resistance of carbon C-29 in pristimerin to these reactions.

Plants from Salacia genus are used in traditional medicine for a wide range of diseases. Previous studies reported bioactive pentacyclic triterpenoids from S. elliptica leaves and branches. In this study, the novel pentacyclic triterpenoid 7α,15α‐dihydroxyfriedelan‐3‐one (1) was obtained from the roots of Salacia elliptica, along with seven known compounds: friedelan‐3‐one (2), friedelan‐3β‐ol (3), friedelan‐1,3‐dione (4), friedelan‐3,15‐dione (5), 15α‐hydroxyfriedelan‐3‐one (6), 15α,26‐dihydroxyfriedelan‐3‐one (7), and 26‐hydroxyfriedelan‐3,15‐dione (8). Additionally, one steroid, spinasterol (9), was also identified. The chemical structures of all compounds were established through ¹H and ¹³C‐NMR. Compound 1 was analysed by additional 2D experiments (HMBC, HSQC, COSY, and NOESY) for complete elucidation. Furthermore, the cytotoxicity of compounds 2, 3, 6, 7 and 8 against the A549 lung cancer cells model was evaluated. The flow cytometry analysis revealed a significant cytotoxic activity similar to that exhibited by the triterpenoid lupeol. Additionally, compounds 2, 3, 6, and 7 were tested for in vitro antifungal activity against Candida, Cryptococcus and Sporothrix strains. However, all compounds showed no activity at the tested concentrations.

Magonia pubescens is a natural species from the Brazilian cerrado biome. Its fruits and seeds are used in the treatment of seborrheic dermatitis, a common inflammatory skin disease. In this work, the known compounds lapachol, stigmasterol, maniladiol and scopoletin were isolated from hexane and dichloromethane extracts of M. pubescens branches. The aqueous extract of this material was fractioned through a liquid-liquid partition and the obtained fractions were analyzed by UHPLC-MS/MS. The results obtained were compared with data from three databases, leading to the putative identification of 51 compounds from different classes, including flavonoids, saponins and triterpenes. The cytotoxicity of aqueous fractions was assayed against breast cancer (MDA-MB-231) and leukemia (THP-1 and K562) cells. The best activity was observed for fraction AE3 against MDA-MB-231 cells (IC₅₀ 30.72 µg.mL^-1).

Botanical biopesticides have emerged as sustainable and eco-friendly alternatives to synthetic pesticides, whose indiscriminate use leads to several drawbacks to human and environmental health. To the best of our knowledge, there have been no reports on M. pubescens’ bioactivity on phytopathogens affecting crops as a potential fungicide or antifeedant. This has encouraged us to investigate the potential of the roots of this plant as a source of biopesticides. The present study reports on the evaluation of the roots extract from Magonia pubescens A. St.-Hill., a species from the Cerrado (Brazilian savannah), on the phytopathogenic fungi Botrytis cinerea, Fusarium oxysporum, and Alternaria alternata. In addition, its insect antifeedant effect was assayed against Chrysodeixis chalcites. Thus, an in vitro test-assay was used to determine the fungicide potential (percentage growth inhibition, % GI) of the ethanolic extract of this plant species, whereas a leaf-disk bioassay on the 5th instar larvae of C. chalcites was performed to evaluate its insecticidal potential. The ethanolic extract was further fractionated by liquid–liquid partition using solvents of increasing polarity. The hexane/dichloromethane fraction exhibited a moderated potency and was similar to the ethanolic extract on the three assayed fungi (around % GI 30 at 1 mg/mL), whereas the n-butanol fraction showed a slight improvement of the fungicide effect against B. cinerea (% GI 39.18 at 1 mg/mL). Moreover, the ethanolic extract exhibited a strong antifeedant activity, with a refusal rate (FR) higher than 90% in both choice and non-choice assays against C. chalcites, while the ethyl acetate and n-butanol fractions behaved as appetite suppressors. These results highlight M. pubescens as a promising source of biopesticides and deserve further investigations to optimize extraction procedures.