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1.
Mol Inform ; 43(7): e202400052, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38994633

RESUMEN

Compound databases of natural products play a crucial role in drug discovery and development projects and have implications in other areas, such as food chemical research, ecology and metabolomics. Recently, we put together the first version of the Latin American Natural Product database (LANaPDB) as a collective effort of researchers from six countries to ensemble a public and representative library of natural products in a geographical region with a large biodiversity. The present work aims to conduct a comparative and extensive profiling of the natural product-likeness of an updated version of LANaPDB and the individual ten compound databases that form part of LANaPDB. The natural product-likeness profile of the Latin American compound databases is contrasted with the profile of other major natural product databases in the public domain and a set of small-molecule drugs approved for clinical use. As part of the extensive characterization, we employed several chemoinformatics metrics of natural product likeness. The results of this study will capture the attention of the global community engaged in natural product databases, not only in Latin America but across the world.


Asunto(s)
Productos Biológicos , Productos Biológicos/química , Productos Biológicos/farmacología , América Latina , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Descubrimiento de Drogas , Quimioinformática , Bases de Datos de Compuestos Químicos
2.
J Nat Prod ; 87(4): 1067-1074, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38631020

RESUMEN

A search for anti-trypanosomal natural compounds from plants collected in El Salvador, a country particularly endemic for Chagas disease, resulted in the isolation of five lignan-type compounds (1-5) from Peperomia pseudopereskiifolia. The lignan derivatives 1, 2, and 4 are new. Their absolute configuration was determined by chemical derivatization. Compounds 1, 5, 6, and 8 exhibited anti-trypanosomal activity against the amastigote form of T. cruzi comparable to that of the existing drug benznidazole.


Asunto(s)
Lignanos , Peperomia , Tripanocidas , Trypanosoma cruzi , Lignanos/farmacología , Lignanos/química , Lignanos/aislamiento & purificación , Trypanosoma cruzi/efectos de los fármacos , El Salvador , Tripanocidas/farmacología , Tripanocidas/química , Tripanocidas/aislamiento & purificación , Estructura Molecular , Peperomia/química , Nitroimidazoles/farmacología , Nitroimidazoles/química , Enfermedad de Chagas/tratamiento farmacológico
3.
Plants (Basel) ; 13(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38337893

RESUMEN

Chagas disease and leishmaniasis are among the most widespread neglected tropical diseases, and their current therapies have limited efficacy and several toxic side effects. The present study reports the chemical and antikinetoplastid profiles of extracts from five Salvadoran Celastraceae species against the Trypanosoma cruzi epimastigotes stage and Leishmania amazonensis and Leishmania donovani promastigote forms. The phytochemical profile evinced the presence of flavonoids, tannins, sterols, and triterpenes as the main components in all plant species, whereas quinonemethide triterpenoids (QMTs) were restricted to the root bark of the studied species. Antikinetoplastid evaluation highlights the root bark extracts from Zinowewia integerrima, Maytenus segoviarum, and Quetzalia ilicina as the most promising ones, exhibiting higher potency against T. cruzi (IC50 0.71-1.58 µg/mL) and L. amazonensis (IC50 0.38-2.05 µg/mL) than the reference drugs, benznidazole (IC50 1.81 µg/mL) and miltefosine (IC50 2.64 µg/mL), respectively. This potent activity was connected with an excellent selectivity index on the murine macrophage J774A.1 cell line. These findings reinforce the potential of QMTs as antikinetoplastid agents for the development of innovative phytopharmaceuticals and the plant species under study as a source of these promising lead compounds.

4.
Pharmaceuticals (Basel) ; 16(10)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37895859

RESUMEN

The number of databases of natural products (NPs) has increased substantially. Latin America is extraordinarily rich in biodiversity, enabling the identification of novel NPs, which has encouraged both the development of databases and the implementation of those that are being created or are under development. In a collective effort from several Latin American countries, herein we introduce the first version of the Latin American Natural Products Database (LANaPDB), a public compound collection that gathers the chemical information of NPs contained in diverse databases from this geographical region. The current version of LANaPDB unifies the information from six countries and contains 12,959 chemical structures. The structural classification showed that the most abundant compounds are the terpenoids (63.2%), phenylpropanoids (18%) and alkaloids (11.8%). From the analysis of the distribution of properties of pharmaceutical interest, it was observed that many LANaPDB compounds satisfy some drug-like rules of thumb for physicochemical properties. The concept of the chemical multiverse was employed to generate multiple chemical spaces from two different fingerprints and two dimensionality reduction techniques. Comparing LANaPDB with FDA-approved drugs and the major open-access repository of NPs, COCONUT, it was concluded that the chemical space covered by LANaPDB completely overlaps with COCONUT and, in some regions, with FDA-approved drugs. LANaPDB will be updated, adding more compounds from each database, plus the addition of databases from other Latin American countries.

5.
Toxins (Basel) ; 15(7)2023 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-37505678

RESUMEN

This study describes a multistage methodology to detect minute amounts of tetrodotoxin in fishes, a plan that may be broadened to include other marine organisms. This methodology was applied to porcupinefish (Diodon hystrix) collected in Punta Chiquirín, El Salvador. A three-stage approach along with post-acquisition processing was employed, to wit: (a) Sample screening by selected reaction monitoring (HPLC-MS/MS-SRM) analyses to quickly identify possible toxin presence via a LC/MS/MS API 3200 system with a triple quadrupole; (b) HPLC-HRFTMS-full scan analyses using an ion trap-Orbitrap spectrometer combined with an MZmine 2-enhanced dereplication-like workflow to collect high-resolution mass spectra; and (c) HPLC-HRMS2 analyses. This is the first time tetrodotoxin has been reported in D. hystrix specimens collected in El Salvador.


Asunto(s)
Espectrometría de Masas en Tándem , Tetraodontiformes , Animales , Espectrometría de Masas en Tándem/métodos , Tetrodotoxina , El Salvador , Cromatografía Liquida/métodos
6.
Bol. latinoam. Caribe plantas med. aromát ; 22(1): 19-36, ene. 2023. tab
Artículo en Inglés | LILACS | ID: biblio-1555028

RESUMEN

Currently, in developing countries, parasitic and bacterial diseases as amebiasis, giardiasis, trichonomiasis, leishmaniasis, trypanosomiasis, tuberculosis, and nocardiasis are a public health problem. The pharmacological treatment for these diseases is not completely effective and causes several side effects in patients. Therefore, the search for new compounds with biological activity is very important to develop new drugs safely and more efficiently. In this study, different organic extracts obtained from thirty-seven species of the Salvadoran flora were evaluated in several in vitro models to determine their potential activity against five protozoa (Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, Leishmania mexicana, and Trypanosoma cruzi) and three bacteria (Acinetobacter baumanni, Mycobacterium tuberculosis, and Nocardia brasiliensis). The results showed the activity of eight extracts with IC50values of less than 100 µg/mL against L. mexicanaand five extracts with MICs values less than <50 µg/mL against M. tuberculosis. Besides, seven plant species showed MICs ≤3.125 µg/mL against N. brasiliensis. Additionally, secondary metabolites (flavonoids and monoterpene oxygenate) previously reported as active were fingerprint by UPLC-MS to establish a potential correlation with the biological activity showed.


Actualmente, en los países en vías de desarrollo, enfermedades parasitarias y bacterianas como la amebiasis, giardiasis, trichonomiasis, leishmaniasis, tripanosomiasis, tuberculosis y nocardiasis son un problema de salud pública. El tratamiento farmacológico de estas enfermedades no es del todo eficaz y provoca varios efectos secundarios en los pacientes. Por lo tanto, la búsqueda de nuevos compuestos con actividad biológica es muy importante para desarrollar nuevos fármacos, seguros y eficaces. En este estudio se evaluaron diferentes extractos orgánicos obtenidos de treinta y siete especies de la flora salvadoreña en varios modelos in vitro para determinar su actividad potencial contra cinco parásitos (Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, Leishmania mexicana y Trypanosoma cruzi) y tres bacterias (Acinetobacter baumanni, Mycobacterium tuberculosis y Nocardia brasiliensis). Los resultados mostraron la actividad de ocho extractos con valores de CI50 menores a 100 µg/mL contra L. mexicana y cinco extractos con valores de CIMs <50 µg/mL contra M. tuberculosis. Además, siete especies de plantas presentaron CIM ≤3,125 µg/mL frente a N. brasilienses. Finalmente, los metabolitos secundarios (flavonoides y monoterpenos oxigenados) previamente reportados como activos fueron determinados por UPLC-MS para establecer una posible correlación con la actividad biológica mostrada.


Asunto(s)
Extractos Vegetales/farmacología , Flora , Antibacterianos/farmacología , Antiparasitarios/farmacología , Parásitos/efectos de los fármacos , Bacterias/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Flavonoides/análisis , Técnicas In Vitro , Extractos Vegetales/química , Pruebas de Sensibilidad Microbiana , Cromatografía Líquida de Alta Presión , Monoterpenos/análisis , El Salvador , Amoeba/efectos de los fármacos , Antibacterianos/química , Mycobacterium tuberculosis , Antiparasitarios/química
7.
Nat Prod Res ; 37(16): 2782-2786, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36239484

RESUMEN

Herpes simplex virus 1 is one of the most prevalent pathogens worldwide. Resistant strains to current anti-viral treatment have been reported, requiring the search for novel anti-virals. Using a qPCR method to assess anti-herpetic activity from natural products, we analyzed 72 plant extracts from El Salvador and identified eighteen methanolic extracts with anti-viral activity of ≥ 75%. Anti-herpetic activity has not been previously reported in fourteen of the plants (Euphorbia lancifolia, Piper tuberculatum, Cordia alliodora, Tecoma stans, Taraxacum officinale, Hamelia patens, Witheringia solanacea, Emilia fosbergii, Gnaphalium viscosum, Citrus aurantium, Ambrosia peruviana, Carica papaya, Solanum hazenii and Melothria pendula). Four extracts were from species with previously reported anti-herpetic activity (Plantago major, Psidium guajava, Sida acuta and Bursera simaruba). These extracts effective anti-viral concentrations (EC50) were between 203 and 6.31 µg/mL, while the selectivity indexes (SI) were between 55.91 and 2.57. Euphorbia lancifolia showed the most effective anti-viral activity (EC50 = 6.31 µg/mL, SI = 51.82).

8.
J Nat Med ; 76(1): 259-267, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34529189

RESUMEN

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, and in Central America, it is considered one of the four most infectious diseases. This study aimed to screen the anti-trypanosomal activity of plant species from Salvadoran flora. Plants were selected through literature search for plants ethnobotanically used for antiparasitic and Chagas disease symptomatology, and reported in Museo de Historia Natural de El Salvador (MUHNES) database. T. cruzi was incubated for 72 h with 2 different concentrations of methanolic extracts of 38 species, among which four species, Piper jacquemontianum, Piper lacunosum, Trichilia havanensis, and Peperomia pseudopereskiifolia, showed the activity (≤ 52.0% viability) at 100 µg/mL. Separation of the methanolic extract of aerial parts from Piper jacquemontianum afforded a new flavanone (4) and four known compounds, 2,2-dimethyl-6-carboxymethoxychroman-4-one (1), 2,2-dimethyl-6-carboxychroman-4-one (2), cardamomin (3), and pinocembrin (5), among which cardamomin exhibited the highest anti-trypanosomal activity (IC50 = 66 µM). Detailed analyses of the spectral data revealed that the new compound 4, named as jaqueflavanone A, was a derivative of pinocembrin having a prenylated benzoate moiety at the 8-position of the A ring.


Asunto(s)
Extractos Vegetales/farmacología , Tripanocidas , Trypanosoma cruzi , Enfermedad de Chagas/tratamiento farmacológico , Humanos , Meliaceae/química , Peperomia/química , Piper/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos
9.
J Nat Prod ; 84(10): 2717-2726, 2021 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-34549952

RESUMEN

The aim of the present study is to report the isolation, structural elucidation, and antiviral evaluation of four new withanolide-type steroids, named nicansteroidins A-D (1-4), together with nine related known compounds (5-13) isolated from the aerial parts of Physalis nicandroides. Their structures were established based on an extensive spectroscopic analysis, including 1D and 2D NMR techniques. Outstandingly, nicansteroidins A and B possess an unusual side chain with an exocyclic double bond on the δ-lactone system, whereas nicansteroidins C and D have an uncommon cycloperoxide functionality in ring A as distinct structural motifs. Their biological evaluation as inhibitors of human immunodeficiency virus type 1 replication revealed that two compounds from this series, 7 and 13, displayed strong inhibition of HIV-1 replication with IC50 values lower than 2 µM. Moreover, cellular mechanism experiments showed that the main target of these compounds in the HIV replication cycle is viral transcription. This study is the first report of withanolide-type steroids as HIV inhibitors and provides insight into their potential as candidates for further preclinical studies.


Asunto(s)
Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Physalis/química , Replicación Viral/efectos de los fármacos , Witanólidos/farmacología , Línea Celular , El Salvador , VIH-1/fisiología , Humanos , Estructura Molecular , Componentes Aéreos de las Plantas/química
10.
Artículo en Inglés | MEDLINE | ID: mdl-33753334

RESUMEN

Leishmaniasis and Chagas are among the most significant neglected tropical diseases. Due to several drawbacks with the current chemotherapy, developing new antikinetoplastid drugs has become an urgent issue. In the present work, a bioassay-guided investigation of the root bark of Maytenus chiapensis on Leishmania amazonensis and Trypanosoma cruzi led to the identification of two D:A-friedo-nor-oleanane triterpenoids (celastroloids), 20ß-hydroxy-tingenone (celastroloid 5) and 3-O-methyl-6-oxo-tingenol (celastroloid 8), as promising antikinetoplastid leads. They displayed higher potency on L. amazonensis promastigotes (50% inhibitory concentrations [IC50s], 0.44 and 1.12 µM, respectively), intracellular amastigotes (IC50s, 0.83 and 1.91 µM, respectively), and T. cruzi epimastigote stage (IC50s, 2.61 and 3.41 µM, respectively) than reference drugs miltefosine and benznidazole. This potency was coupled with an excellent selectivity index on murine macrophages. Mechanism of action studies, including mitochondrial membrane potential (Δψm) and ATP-level analysis, revealed that celastroloids could induce apoptotic cell death in L. amazonensis triggered by the mitochondria. In addition, the structure-activity relationship is discussed. These findings strongly underline the potential of celastroloids as lead compounds to develop novel antikinetoplastid drugs.


Asunto(s)
Antiprotozoarios , Leishmania mexicana , Leishmaniasis , Maytenus , Trypanosoma cruzi , Animales , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Leishmaniasis/tratamiento farmacológico , Ratones
11.
Rev. peru. med. exp. salud publica ; 35(4): 581-589, oct.-dic. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-985794

RESUMEN

RESUMEN Objetivo Evaluar el efecto analgésico del extracto etanólico de las hojas de Pereskia lychnidiflora, la prospección de metabolitos secundarios y el análisis toxicológico. Materiales y métodos La actividad analgésica fue evaluada mediante la prueba del ácido acético y la formalina en ratones NIH a una concentración de 30, 50 y 100 mg/kg de peso corporal, utilizando como control Ibuprofeno a 200 mg/kg y agua destilada como blanco. La prospección de metabolitos secundarios se realizó por el método de cromatografía de capa fina y la toxicidad del extracto fue evaluada in vivo según la dosis máxima de 2000 mg/kg de peso corporal. Resultados La prospección fitoquímica determinó la presencia de alcaloides, taninos, triterpenos y esteroles como mayores constituyentes químicos. Se determinó que el extracto etanólico de Pereskia lychnidiflora posee una actividad analgésica similar al Ibuprofeno. No se observaron signos de toxicidad en los ratones de experimentación y se clasifica el extracto como no tóxico con una DL50 mayor de 2000 mg/kg. Conclusión El extracto etanólico de Pereskia lychnidiflora tiene un efecto analgésico antiinflamatorio que podría estar condicionado por la presencia de alcaloides, taninos y esteroles (terpenoides) presentes en esta especie vegetal y puede ser clasificado como no tóxico.


ABSTRACT Objective To evaluate the analgesic effect of the ethanolic extract of the leaves of Pereskia lychnidiflora, the prospection of secondary metabolites and the toxicologic analysis. Materials and Methods Analgesic activity was evaluated by testing acetic acid and formalin in NIH mice at a concentration of 30, 50 and 100 mg/kg body weight, using Ibuprofen control at 200 mg/kg and distilled water as the target. Secondary metabolites were prospected using the thin layer chromatography method and the toxicity of the extract was evaluated in vivo according to the maximum dose of 2,000 mg/kg body weight. Results Phytochemical prospecting determined the presence of alkaloids, tannins, triterpenes, and sterols as major chemical constituents. The ethanolic extract of Pereskia lychnidiflora was found to have an analgesic activity similar to ibuprofen. No signs of toxicity were observed in the experimental mice and the extract is classified as non-toxic with a DL50 greater than 2,000 mg/kg. Conclusions The ethanolic extract of Pereskia lychnidiflora has an anti- inflammatory analgesic effect that could be conditioned by the presence of alkaloids, tannins, and sterols (terpenoids) present in this species and can be classified as non-toxic.


Asunto(s)
Animales , Masculino , Ratones , Extractos Vegetales/toxicidad , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Cactaceae , Analgesia , Analgésicos/toxicidad , Analgésicos/uso terapéutico , Fitoterapia , Extractos Vegetales/farmacología , Extractos Vegetales/química , Etanol , Fitoquímicos/análisis , Analgésicos/farmacología , Analgésicos/química
12.
Rev Peru Med Exp Salud Publica ; 35(4): 581-589, 2018.
Artículo en Español | MEDLINE | ID: mdl-30726415

RESUMEN

OBJECTIVE: To evaluate the analgesic effect of the ethanolic extract of the leaves of Pereskia lychnidiflora, the prospection of secondary metabolites and the toxicologic analysis. MATERIALS AND METHODS: Analgesic activity was evaluated by testing acetic acid and formalin in NIH mice at a concentration of 30, 50 and 100 mg/kg body weight, using Ibuprofen control at 200 mg/kg and distilled water as the target. Secondary metabolites were prospected using the thin layer chromatography method and the toxicity of the extract was evaluated in vivo according to the maximum dose of 2,000 mg/kg body weight. RESULTS: Phytochemical prospecting determined the presence of alkaloids, tannins, triterpenes, and sterols as major chemical constituents. The ethanolic extract of Pereskia lychnidiflora was found to have an analgesic activity similar to ibuprofen. No signs of toxicity were observed in the experimental mice and the extract is classified as non-toxic with a DL50 greater than 2,000 mg/kg. CONCLUSIONS: The ethanolic extract of Pereskia lychnidiflora has an anti- inflammatory analgesic effect that could be conditioned by the presence of alkaloids, tannins, and sterols (terpenoids) present in this species and can be classified as non-toxic.


OBJETIVO: Evaluar el efecto analgésico del extracto etanólico de las hojas de Pereskia lychnidiflora, la prospección de metabolitos secundarios y el análisis toxicológico. MATERIALES Y MÉTODOS: La actividad analgésica fue evaluada mediante la prueba del ácido acético y la formalina en ratones NIH a una concentración de 30, 50 y 100 mg/kg de peso corporal, utilizando como control Ibuprofeno a 200 mg/kg y agua destilada como blanco. La prospección de metabolitos secundarios se realizó por el método de cromatografía de capa fina y la toxicidad del extracto fue evaluada in vivo según la dosis máxima de 2000 mg/kg de peso corporal. RESULTADOS: La prospección fitoquímica determinó la presencia de alcaloides, taninos, triterpenos y esteroles como mayores constituyentes químicos. Se determinó que el extracto etanólico de Pereskia lychnidiflora posee una actividad analgésica similar al Ibuprofeno. No se observaron signos de toxicidad en los ratones de experimentación y se clasifica el extracto como no tóxico con una DL50 mayor de 2000 mg/kg. CONCLUSIÓN: El extracto etanólico de Pereskia lychnidiflora tiene un efecto analgésico antiinflamatorio que podría estar condicionado por la presencia de alcaloides, taninos y esteroles (terpenoides) presentes en esta especie vegetal y puede ser clasificado como no tóxico.


Asunto(s)
Analgesia , Analgésicos/toxicidad , Analgésicos/uso terapéutico , Cactaceae , Fitoterapia , Extractos Vegetales/toxicidad , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Analgésicos/química , Analgésicos/farmacología , Animales , Etanol , Masculino , Ratones , Fitoquímicos/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacología
13.
Phytochemistry ; 142: 21-29, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28666142

RESUMEN

As part of a bioprospecting program aimed at the discovery of undescribed natural products from Salvadoran and Peruvian flora, the phytochemical investigations of four Celastraceae species, Celastrus vulcanicola, Maytenus segoviarum, Maytenus jeslkii, and Maytenus cuzcoina, were performed. The current study reports the isolation and structural characterization of five previously undescribed macrolide sesquiterpene pyridine alkaloids, named vulcanicoline-A, cuzcoinine, vulcanicoline-B, jelskiine, and vulcanicoline-C, along with sixteen known alkaloids. The structures of the alkaloids were established by spectrometric and extensive 1D and 2D NMR spectroscopic analysis, including COSY, HSQC, HMBC, and ROESY experiments. The absolute configurations of alkaloids were proposed based on optical rotation sign, and biogenetic considerations. This study represents the first phytochemical analysis of Maytenus segoviarum.


Asunto(s)
Alcaloides/aislamiento & purificación , Celastraceae/química , Piridinas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Alcaloides/química , Celastrus , El Salvador , Maytenus/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Perú , Piridinas/química , Sesquiterpenos/química
14.
J Nat Prod ; 79(10): 2538-2544, 2016 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-27754693

RESUMEN

Calea urticifolia (Asteraceae: Asteroideae) has long been used as a traditional medicine in El Salvador to treat arthritis and fever, among other illnesses. The chloroform extract of the leaves of C. urticifolia showed potent inhibition of recombinant human monoamine oxidases (MAO-A and -B). Further bioassay-guided fractionation led to the isolation of a flavonoid, acacetin, as the most prominent MAO inhibitory constituent, with IC50 values of 121 and 49 nM for MAO-A and -B, respectively. The potency of MAO inhibition by acacetin was >5-fold higher for MAO-A (0.121 µM vs 0.640 µM) and >22-fold higher for MAO-B (0.049 µM vs 1.12 µM) as compared to apigenin, the closest flavone structural analogue. Interaction and binding characteristics of acacetin with MAO-A and -B were determined by enzyme-kinetic assays, enzyme-inhibitor complex binding, equilibrium-dialysis dissociation analyses, and computation analysis. Follow-up studies showed reversible binding of acacetin with human MAO-A and -B, resulting in competitive inhibition. Acacetin showed more preference toward MAO-B than to MAO-A, suggesting its potential for eliciting selective pharmacological effects that might be useful in the treatment of neurological and psychiatric disorders. In addition, the binding modes of acacetin at the enzymatic site of MAO-A and -B were predicted through molecular modeling algorithms, illustrating the high importance of ligand interaction with negative and positive free energy regions of the enzyme active site.


Asunto(s)
Asteraceae/química , Flavonas/aislamiento & purificación , Flavonas/farmacología , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Inhibidores de la Monoaminooxidasa/farmacología , Dominio Catalítico , Relación Dosis-Respuesta a Droga , El Salvador , Flavonas/química , Humanos , Concentración 50 Inhibidora , Modelos Moleculares , Estructura Molecular , Inhibidores de la Monoaminooxidasa/química , Relación Estructura-Actividad , Factores de Tiempo
16.
Phytochemistry ; 72(4-5): 385-90, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21315389

RESUMEN

Two ent-rosane- (cuzcol, 1 and 6-dehydroxycuzcol, 2) and a abietatriene- (salvadoriol, 3) type diterpenoids have been isolated from Maytenus cuzcoina and Crossopetalum uragoga, respectively, along with five known diterpene compounds (4-8). Their stereostructures have been elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR techniques, and computational data. The absolute configuration of cuzcol was determined by application of Riguera ester procedure. This is the first instance of isolation of ent-rosane diterpenoids from species of the Celastraceae. The isolated diterpenes were found to be potent anti-tumour-promoter agents, and carnosol (7) also showed a remarkable chemopreventive effect in an in vivo two-stage carcinogenesis model.


Asunto(s)
Abietanos/aislamiento & purificación , Abietanos/farmacología , Anticarcinógenos/aislamiento & purificación , Anticarcinógenos/farmacología , Celastraceae/química , Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Maytenus/química , Modelos Biológicos , Abietanos/química , Animales , Anticarcinógenos/química , Estudios Cruzados , Diterpenos/química , Antígenos Nucleares del Virus de Epstein-Barr/efectos de los fármacos , Femenino , Ratones , Ratones Endogámicos ICR , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Papiloma/tratamiento farmacológico , Perú , Corteza de la Planta/química , Raíces de Plantas/química , Piel/efectos de los fármacos
17.
J Nat Prod ; 68(7): 1018-21, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16038541

RESUMEN

Five new lupane triterpenes (1-5), in addition to 24 known ones, were isolated from Maytenus cuzcoina and M. chiapensis. Their structures were elucidated on the basis of spectroscopic analysis, including homonuclear and heteronuclear correlation NMR (COSY, ROESY, HSQC, and HMBC) experiments. The compounds were assayed for antimicrobial and cytotoxic activities, with 3-epi-betulinic acid and 28,30-dihydroxy-3-oxolup-20(29)-ene showing moderate cytotoxicity.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Bacterias/efectos de los fármacos , Maytenus/química , Triterpenos/aislamiento & purificación , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Chlorocebus aethiops , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Triterpenos Pentacíclicos , Perú , Triterpenos/química , Triterpenos/farmacología , Células Tumorales Cultivadas , Ácido Betulínico
18.
J Nat Prod ; 67(1): 14-8, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14738378

RESUMEN

The new sesquiterpene pyridine alkaloids chiapenines ES-I (1), ES-II (2), ES-III (3), and ES-IV (4), in addition to the known alkaloids wilfordine (5), alatamine (6), wilforidine (7), alatusinine (8), euonine (9), euonymine (10), ebenifoline E-I (11), forrestine (12), mayteine (13), and 4-hydroxy-7-epi-chuchuhuanine E-V (14), were isolated from the leaves of Maytenus chiapensis. Their structures were elucidated by 1D and 2D NMR spectroscopy, including homonuclear and heteronuclear correlation (COSY, ROESY, HSQC, and HMBC) experiments. Wilfordine, alatusinine, and euonine exhibited strong antifeedant activity against Spodoptera littoralis.


Asunto(s)
Alcaloides/aislamiento & purificación , Insecticidas/aislamiento & purificación , Maytenus/química , Plantas Medicinales/química , Piridinas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Alcaloides/química , Alcaloides/farmacología , Animales , Áfidos/efectos de los fármacos , Células Cultivadas , El Salvador , Conducta Alimentaria/efectos de los fármacos , Insecticidas/química , Insecticidas/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Piridinas/química , Piridinas/farmacología , Sesquiterpenos/química , Sesquiterpenos/farmacología , Spodoptera/efectos de los fármacos
19.
J Nat Prod ; 66(8): 1047-50, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12932121

RESUMEN

Two new sesquiterpenoids (1 and 2) with a dihydro-beta-agarofuran skeleton were isolated from Crossopetalum tonduzii. Their structures were elucidated on the basis of spectral analysis, including homonuclear and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC, and HMBC). Their absolute configurations were determined by CD studies on 3, the benzoylated derivative of 1. Chemical correlations have allowed the absolute configurations of 4 and 5, two previously known dihydro-beta-agarofuran analogues, to be reported for the first time. Compounds 1, 2, and 5 showed strong antitumor-promoting effects on Epstein-Barr virus early antigen (EBV-EA) activation.


Asunto(s)
Anticarcinógenos/aislamiento & purificación , Antígenos Virales/efectos de los fármacos , Celastraceae/química , Plantas Medicinales/química , Sesquiterpenos/aislamiento & purificación , Acetilación , Anticarcinógenos/química , Anticarcinógenos/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Panamá , Sesquiterpenos/química , Sesquiterpenos/farmacología , Estereoisomerismo
20.
J Nat Prod ; 66(4): 572-4, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12713421

RESUMEN

Five new dihydro-beta-agarofuran sesquiterpenes (1-5) were isolated from the leaves of Maytenus chiapensis. The structures of 1-5 were determined by means of 1D and 2D NMR techniques. A semiselective HMBC technique was applied in order to obtain complete (13)C NMR assignments. Absolute configurations were determined by CD studies and chemical correlations and on biogenetic grounds. Compound 4 showed weak activity against a multidrug-resistant Leishmania tropica line.


Asunto(s)
Leishmania tropica/efectos de los fármacos , Maytenus/química , Plantas Medicinales/química , Sesquiterpenos/aislamiento & purificación , Animales , Isótopos de Carbono , Línea Celular/efectos de los fármacos , Dicroismo Circular , Resistencia a Múltiples Medicamentos , El Salvador , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Estereoisomerismo
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