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1.
J Phys Chem A ; 123(16): 3535-3542, 2019 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-30943033

RESUMEN

A spectrum of field-ionized triplet Rydberg states of gerade symmetry H2 has been measured, excited from the υ″ = 0, N″ = 1-3 rovibrational levels of the metastable c3Πu-2pπ state in a 6 keV fast molecular beam. The field-ionized spectrum is kinetic energy labeled in order to separate it from the well-studied υ+ ≥ 1 autoionization spectrum. The spectrum consists of both ns and nd Rydberg series with n between 10 and 28 converging to the υ+ = 0, N+ = 1-3 levels of the X+ 2Σg+ ground state of H2+. Transitions with changes in vibration and/or rotation are also identified. The spectral positions of 59 transitions in the field ionization spectrum are identified and assigned quantum numbers using the predictions of multichannel quantum-defect theory (MQDT). The transition energies and subsequent effective quantum defects are compared between the experiment and theory. Most of the observed transitions, within the experimental uncertainty of 0.2 cm-1, agree with the energies predicted by MQDT.

2.
Cell Mol Biol (Noisy-le-grand) ; 62(9): 20-6, 2016 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-27585257

RESUMEN

Antimicrobial herbal compounds are one of the important medical resources, and in order to help alleviate the spread of the pediatric infectious diseases, identification of additional bioactive phytochemicals and herbal extracts will be practical in treating illnesses. In the present work, antimicrobial activities various extracts of Tordylium persicum Boiss. & Hausskn aerial parts were determined against five Gram-positive bacteria, five Gram-negative bacteria, two fungi, and Echinococcus granulosus. Antimicrobial activities were assayed using both disk diffusion and microbroth dilution methods. Scolicidal activity was assayed by the Smyth and Barrett method. Also total phenol and total flavonoid contents for plant extracts were assayed. Results showed that the methanolic extract was more effective on all microbes. The results showed that Streptococcus pyogenes was the most susceptible to the methanolic extract (MIC = 25.9 ± 0.0 µg/mL), while Proteus vulgaris was the most resistant strain (MIC = 295.3 ± 0.0 µg/mL) among all bacteria evaluated. The extracts showed significant activity versus E. granulosus (P < 0.5) with dose-dependent inhibitions of the protoscolices. The high concentration of total polyphenolics (294.5 ± 0.1 GAE/g DW) and flavonoids (105.7 ± 0.3 mg CE/g DW) may be responsible for these activities. Our study is first evaluation on antimicrobial and scolicidal activities of T. persicum. Due to the appearance of antibiotic-resistance, ourstudy suggested that methanol extracts of this plant are appropriate candidate for traditional curative uses and it can be utilized in the pediatric infectious disease therapy, especially pediatric infectious disease.


Asunto(s)
Antiinfecciosos/farmacología , Apiaceae/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Extractos Vegetales/farmacología , Antiinfecciosos/química , Antiinfecciosos/uso terapéutico , Apiaceae/metabolismo , Preescolar , Enfermedades Transmisibles/tratamiento farmacológico , Enfermedades Transmisibles/microbiología , Farmacorresistencia Bacteriana/efectos de los fármacos , Flavonoides/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Hongos/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Polifenoles/química , Polifenoles/aislamiento & purificación , Polifenoles/farmacología
3.
Cell Mol Biol (Noisy-le-grand) ; 62(9): 57-68, 2016 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-27585263

RESUMEN

Plants belonging to the genus Allium are widely cultivated and used all over the world as food and medicinal plants. Since ancient times, these plants, particularly garlic (Allium sativum L.) and onion (Allium cepa L.), have represented important components of typical recipes and traditional healing systems. Not the least of which, their use as food biopreservatives is well documented, due to the relevant antibacterial activity of their extracts and essential oils. In addition to garlic and onion, this review article deals with the main members of the genus Allium, including A. ampeloprasum (Leek), A. schoenoprasum (Chive) and A. ascalonicum (Shallot), focusing both on their ethnonutritional uses and potential as promising food biopreservative agents. Noteworthy, recent research has demonstrated Allium derivatives to be novel components in active edible coatings as well as nanoformulates.


Asunto(s)
Ajo/química , Antibacterianos/química , Cebollino/química , Cebollino/metabolismo , Ajo/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Cebollas/química , Cebollas/metabolismo , Plantas Medicinales/química , Plantas Medicinales/metabolismo
4.
Cell Mol Biol (Noisy-le-grand) ; 62(6): 8-16, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27262795

RESUMEN

Scandix pecten-veneris L. or Shepherd's-needle is a weed species used in some countries for medicinal purposes. In this study S. pecten-veneris leaves were shade dried, powdered and extracted with methanol. The purpose of this study was to assay the in vitro mutagenic, antimutagenic, antioxidant, antilipoxygenase and antimicrobial activities of S. pecten-veneris leaf extract. The methanolic extract indicated no mutagenicity when tested with Salmonella typhimurium strains TA98 and TA100. Antimutagenic activity was reported with inhibition of mutagenicity in a concentration dependent fashion. The methanolic extract demonstrated antioxidant activity in the DPPH radical-scavenging test (IC50 = 4.57 mg/mL), comparable to ascorbic acid and BHT. Moreover, the extract presented a remarkable and potent inhibition against soybean lipoxygenase (IC50 = 641.57 µg/mL). The methanolic extract was examined for its antimicrobial powers against four different bacteria with MIC values >100. Our results introduced this plant as a useful factor for the treatment of cancer, inflammatory and infectious diseases.


Asunto(s)
Antiinfecciosos/farmacología , Antimutagênicos/farmacología , Antioxidantes/farmacología , Apiaceae/química , Inhibidores de la Lipooxigenasa/farmacología , Mutágenos/toxicidad , Extractos Vegetales/farmacología , Antifúngicos/farmacología , Depuradores de Radicales Libres/farmacología , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Salmonella typhimurium/efectos de los fármacos
5.
Curr Med Chem ; 22(30): 3462-71, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26502950

RESUMEN

During past two decades, plant-derived bioactive compounds have been reported as novel therapeutic agents for prevention and/or mitigation of different human diseases such as cancer, inflammation, cardiovascular and neurodegenerative diseases. Hesperidin is known as one of the most common and bioactive constituents of Citrus (C) species which possesses multiple health-promotion effects. A plethora of scientific literature reported that hesperidin possesses in-vitro and in-vivo anticancer activities. In addition, there are numerous scientific evidences regarding the molecular mechanisms of anticancer activities of hesperidin and its aglycone, hesperetin. However, in this case, the number of comprehensive reviews on molecular mechanisms underlying the anticancer effects of hesperidin is sparse. Therefore, in this work we present a critical review of the available literature regarding the molecular mechanisms of the anticancer effects of hesperidin and its aglycone, hesperetin.


Asunto(s)
Antineoplásicos/farmacología , Hesperidina/farmacología , Neoplasias/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Anticarcinógenos/química , Anticarcinógenos/farmacología , Anticarcinógenos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Citrus/química , Hesperidina/uso terapéutico , Humanos
6.
Curr Med Chem ; 19(14): 2176-228, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22414104

RESUMEN

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined by the WHO. Furthermore, malaria (caused by various Plasmodium species) can be considered a neglected disease in certain countries and with regard to availability and affordability of the antimalarials. Living organisms, especially plants, provide an innumerable number of molecules with potential for the treatment of many serious diseases. The current review attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs. In part I, a general description of the diseases, the current state of therapy and need for new therapeuticals, assay methods and strategies applied in the search for new plant derived natural products against these diseases and an overview on natural products of terpenoid origin with antiprotozoal potential were given. The present part II compiles the current knowledge on natural products with antiprotozoal activity that are derived from the shikimate pathway (lignans, coumarins, caffeic acid derivatives), quinones of various structural classes, compounds formed via the polyketide pathways (flavonoids and related compounds, chromenes and related benzopyrans and benzofurans, xanthones, acetogenins from Annonaceae and polyacetylenes) as well as the diverse classes of alkaloids. In total, both parts compile the literature on almost 900 different plant-derived natural products and their activity data, taken from over 800 references. These data, as the result of enormous efforts of numerous research groups world-wide, illustrate that plant secondary metabolites represent an immensely rich source of chemical diversity with an extremely high potential to yield a wealth of lead structures towards new therapies for NTDs. Only a small percentage, however, of the roughly 200,000 plant species on earth have been studied chemically and only a small percentage of these plants or their constituents has been investigated for antiprotozoal activity. The repository of plant-derived natural products hence deserves to be investigated even more intensely than it has been up to present.


Asunto(s)
Antiprotozoarios/uso terapéutico , Productos Biológicos/uso terapéutico , Enfermedades Desatendidas/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Plantas Medicinales/química , Infecciones por Protozoos/tratamiento farmacológico , Animales , Antiprotozoarios/química , Antiprotozoarios/metabolismo , Productos Biológicos/química , Productos Biológicos/metabolismo , Humanos , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Plantas Medicinales/metabolismo
7.
Curr Med Chem ; 19(14): 2128-75, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22414103

RESUMEN

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined as such by WHO due to the neglect of financial investment into research and development of new drugs by a large part of pharmaceutical industry and neglect of public awareness in high income countries. Another major tropical protozoan disease is malaria (caused by various Plasmodium species), which -although not mentioned currently by the WHO as a neglected disease- still represents a major problem, especially to people living under poor circumstances in tropical countries. Malaria causes by far the highest number of deaths of all protozoan infections and is often (as in this review) included in the NTDs. The mentioned diseases threaten many millions of lives world-wide and they are mostly associated with poor socioeconomic and hygienic environment. Existing therapies suffer from various shortcomings, namely, a high degree of toxicity and unwanted effects, lack of availability and/or problematic application under the life conditions of affected populations. Development of new, safe and affordable drugs is therefore an urgent need. Nature has provided an innumerable number of drugs for the treatment of many serious diseases. Among the natural sources for new bioactive chemicals, plants are still predominant. Their secondary metabolism yields an immeasurable wealth of chemical structures which has been and will continue to be a source of new drugs, directly in their native form and after optimization by synthetic medicinal chemistry. The current review, published in two parts, attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs.


Asunto(s)
Antiprotozoarios/uso terapéutico , Productos Biológicos/uso terapéutico , Enfermedades Desatendidas/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Plantas Medicinales/química , Plantas Medicinales/metabolismo , Infecciones por Protozoos/tratamiento farmacológico , Animales , Antiprotozoarios/química , Antiprotozoarios/metabolismo , Productos Biológicos/química , Productos Biológicos/metabolismo , Humanos , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/metabolismo
8.
Pharm Biol ; 50(4): 474-80, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22136358

RESUMEN

CONTEXT: Solanum erianthum D. Don and Solanum macranthum Dunal (Solanaceae) are widely used in traditional medicine. The leaves act as an abortifacient and in particular to treat leucorrhoea, sores, and skin irritations. OBJECTIVE: This study was undertaken to characterize the volatile constituents of the leaf and fruit essential oils of S. erianthum and S. macranthum; their antimicrobial and in vitro cytotoxic bioassay against human breast and prostate tumor cells. METHODS: The volatile oils were obtained by hydrodistillation and analyzed for their constituents by gas chromatography-mass spectrometry (GC-MS). Minimum Inhibitory Concentrations (MIC) were determined using the microbroth dilution technique while the cytotoxic potentials were evaluated using the Cell Titre 96((R)) AQ(ueous) Non-Radioactive Cell Proliferation Assay method. RESULTS: Solanum erianthum essential oils were characterized by the abundance of α-terpinolene (17.8%), α-phellandrene (17.5%), p-cymene (15.7%) and ß-pinene (11.7%) in the leaves; α-humulene (23.1%), humulene epoxide II (20.0%), caryophyllene oxide (16.5%), methyl salicylate (11.8%) and ß-caryophyllene (10.9%) in the fruits. The leaf oil of S. macranthum consisted of (E)-phytol (29.0%), pentadecanal (28.1%) and pentadecane (7.7%) while the major fruit oil constituents were α-humulene (36.5%), ß-caryophyllene (17.8%), ethyl palmitate (9.4%), and methyl salicylate (8.2%). Solanum erianthum leaf volatile oil demonstrated potent inhibitory activity against Hs 578T and PC-3 human breast and prostate tumor cells respectively. In addition, the Solanum essential oils exhibited significant antimicrobial activity (19.5-625 µg/mL) on pathogens employed in the assay. CONCLUSION: The Solanum essential oils possess strong antimicrobial activity in addition to the potent cytotoxic potential of S. erianthum leaf oil against Hs 578T and PC-3 cells.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos Fitogénicos/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Solanaceae , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Destilación , Femenino , Frutas , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Hojas de la Planta , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Plantas Medicinales , Neoplasias de la Próstata/patología , Solanaceae/química
9.
Curr Med Chem ; 19: 2128-2175, 2012.
Artículo en Inglés | LILACS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: biblio-1022985

RESUMEN

Infections with protozoan parasites are a major cause of disease and mortality in many tropical countries of the world. Diseases caused by species of the genera Trypanosoma (Human African Trypanosomiasis and Chagas Disease) and Leishmania (various forms of Leishmaniasis) are among the seventeen "Neglected Tropical Diseases" (NTDs) defined as such by WHO due to the neglect of financial investment into research and development of new drugs by a large part of pharmaceutical industry and neglect of public awareness in high income countries. Another major tropical protozoan disease is malaria (caused by various Plasmodium species), which -although not mentioned currently by the WHO as a neglected disease- still represents a major problem, especially to people living under poor circumstances in tropical countries. Malaria causes by far the highest number of deaths of all protozoan infections and is often (as in this review) included in the NTDs. The mentioned diseases threaten many millions of lives world-wide and they are mostly associated with poor socioeconomic and hygienic environment. Existing therapies suffer from various shortcomings, namely, a high degree of toxicity and unwanted effects, lack of availability and/or problematic application under the life conditions of affected populations. Development of new, safe and affordable drugs is therefore an urgent need. Nature has provided an innumerable number of drugs for the treatment of many serious diseases. Among the natural sources for new bioactive chemicals, plants are still predominant. Their secondary metabolism yields an immeasurable wealth of chemical structures which has been and will continue to be a source of new drugs, directly in their native form and after optimization by synthetic medicinal chemistry. The current review, published in two parts, attempts to give an overview on the potential of such plant-derived natural products as antiprotozoal leads and/or drugs in the fight against NTDs.


Asunto(s)
Plantas Medicinales/metabolismo , Plantas Medicinales/química , Infecciones por Protozoos/tratamiento farmacológico , Productos Biológicos/metabolismo , Productos Biológicos/uso terapéutico , Productos Biológicos/química , Humanos , Extractos Vegetales/metabolismo , Extractos Vegetales/uso terapéutico , Extractos Vegetales/química , Animales , Fitoterapia , Antiprotozoarios/metabolismo , Antiprotozoarios/uso terapéutico , Antiprotozoarios/química
10.
West Indian Med J ; 56(1): 5-10, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17621837

RESUMEN

Epingaione (4-Methyl-1-(5-methyl-2, 3,4,5-tetrahydro-[2,3']bifuranyl-5-yl)-pentan-2-one) was isolated as one of the major lipophilic secondary metabolites from the leaves and stems of Bontia daphnoides L. The compound gave 79.24% and 50.83% anti-proliferation/cytotoxic activity on the human SH-SY5Y neuroblastoma and TE-671 sarcoma cells in vitro at 50 pg/mL, respectively. Epingaione was transformed into eleven derivatives under laboratory conditions using ethanol, some gave greater anti-proliferation/cytotoxic activity on the cancer cell lines tested. One of the derivatives (compound 2) with enhanced cytotoxic activity was elucidated as 5'-Ethoxy-5-methyl-5-(4-methyl-2-oxo-pentyl)-2,3,4,5-tetrahydro-5'H-[2,3']bifuranyl-2'-one. Both epingaione and compound 2 caused an accumulation of arrested or dead SH-SY5Y neuroblastoma in the m-phase of the cell cycle as revealed by the m-phase specific marker KE 67.


Asunto(s)
Furanos/farmacología , Myoporaceae , Neuroblastoma/tratamiento farmacológico , Pentanonas/farmacología , Fitoterapia , Sarcoma/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Ensayos de Selección de Medicamentos Antitumorales , Furanos/química , Humanos , Pentanonas/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta , Tallos de la Planta
11.
West Indian med. j ; 56(1): 5-10, Jan. 2007.
Artículo en Inglés | LILACS | ID: lil-471845

RESUMEN

Epingaione (4-Methyl-1-(5-methyl-2, 3,4,5-tetrahydro-[2,3']bifuranyl-5-yl)-pentan-2-one) was isolated as one of the major lipophilic secondary metabolites from the leaves and stems of Bontia daphnoides L. The compound gave 79.24and 50.83anti-proliferation/cytotoxic activity on the human SH-SY5Y neuroblastoma and TE-671 sarcoma cells in vitro at 50 pg/mL, respectively. Epingaione was transformed into eleven derivatives under laboratory conditions using ethanol, some gave greater anti-proliferation/cytotoxic activity on the cancer cell lines tested. One of the derivatives (compound 2) with enhanced cytotoxic activity was elucidated as 5'-Ethoxy-5-methyl-5-(4-methyl-2-oxo-pentyl)-2,3,4,5-tetrahydro-5'H-[2,3']bifuranyl-2'-one. Both epingaione and compound 2 caused an accumulation of arrested or dead SH-SY5Y neuroblastoma in the m-phase of the cell cycle as revealed by the m-phase specific marker KE 67.


La epingaiona (4-Metil-1-(5-metil-2,3,4,5-tetrahidro-[2,3']bifuranil-5-il)-pentan-2-uno) fue aislada como uno de los principales metabolitos lipofilicos secundarios de las hojas y tallos de Bontia daphnoides L. El compuesto produjo 79.24 % y 50.83 % de actividad citotóxica/anti-proliferación sobre el neuroblastoma humano SH-SY5Y y las células del sarcoma TE-671 in vitro a 50 µg/mL, respectivamente. La epingaiona fue transformada en once derivados en condiciones de laboratorio, utilizando etanol. Algunos produjeron mayor actividad citotóxica y antiproliferativa sobre las líneas celulares cancerosas sometidas a ensayo. Uno de los derivados (compuesto 2) de elevada actividad citotóxica fue identificado como 5'-Etoxi-5-metil-5-(4-metil-2-oxo-pentil)-2,3,4,5-tetrahidro-5'H- [2,3']bifuranil-2'-uno. Tanto la epingaiona como el compuesto 22 causaron una acumulación de neuroblastomas SH-SY5Y muertos o detenidos en la fase m del ciclo celular, según lo revela el marcador KE 67 específico de la fase m.


Asunto(s)
Humanos , Fitoterapia , Furanos/farmacología , Myoporaceae , Neuroblastoma/tratamiento farmacológico , Pentanonas/farmacología , Sarcoma/tratamiento farmacológico , Tallos de la Planta , Ensayos de Selección de Medicamentos Antitumorales , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta , Furanos/química , Línea Celular Tumoral , Pentanonas/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular
12.
Mini Rev Med Chem ; 3(6): 540-56, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12871157

RESUMEN

Man has relied on plants as a source of medicinal agents for centuries. Today, with the specter of antibiotic resistance, emerging infectious diseases, and cancers, phytochemicals continue to provide new structural leads for the chemotherapeutic industry. A number of triterpenoids have shown promise as antineoplastic agents. Members of the cycloartane, lupane, ursane, oleanane, friedelane (especially quinone methides), dammarane, cucurbitacin, and limonoid triterpenoids, have demonstrated anti-proliferative activity on various cancer cell lines. This review covers the recent developments regarding antineoplastic/cytotoxic triterpenoids, excluding saponins, from higher plants.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Plantas/química , Triterpenos/farmacología , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Saponinas/química , Saponinas/aislamiento & purificación , Saponinas/farmacología , Relación Estructura-Actividad , Triterpenos/química , Triterpenos/aislamiento & purificación , Células Tumorales Cultivadas/efectos de los fármacos
13.
Planta Med ; 67(1): 65-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11270725

RESUMEN

The crude dichloromethane bark extract of Salacia petenensis (Hippocrateaceae) from Monteverde, Costa Rica, shows antibacterial and cytotoxic activity. Bioactivity-directed separation led to the isolation of tingenone and netzahualcoyonol as the biologically active materials. Also isolated from the extract were 3-methoxyfriedel-2-en-1-one (a new natural product) and 29-hydroxyfriedelan-3-one. The structures of these compounds were elucidated on the basis of NMR spectral analysis. Molecular orbital calculations have been carried out using the semi-empirical PM3 and Hartee-Fock 3-21G ab initio techniques on the quinone-methide nortriterpenoids tingenone and netzahualcoyonol, as well as on the nucleotide bases adenine, guanine, cytosine, and thymine. The molecular orbital calculations suggest that a possible mode of cytotoxic action of quinone-methide triterpenoids involves quasi-intercalative interaction of the compounds with DNA followed by nucleophilic addition of the DNA base to carbon-6 of the triterpenoid.


Asunto(s)
Indolquinonas , Indoles/aislamiento & purificación , Quinonas/aislamiento & purificación , Rosales/química , Triterpenos/aislamiento & purificación , Indoles/química , Modelos Moleculares , Estructura Molecular , Quinonas/química , Triterpenos/química
14.
Chem Pharm Bull (Tokyo) ; 48(11): 1776-7, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11086913

RESUMEN

The synthesis of a series of diacetylenic compounds related to the natural product falcarindiol has been carried out. Unsymmetrical diacetylenes were prepared by a modification of the Cadiot-Chodkiewicz coupling reaction, while a Glaser coupling was used to prepare symmetrical diacetylenes. These compounds have been tested for in vitro cytotoxic activity against Hep-G2, and H-4-II-E cell lines. Diacetylenes with additional unsaturation at C-1, 2, appended with hydroxyl groups at C-3 and C-8, or with long hydrophobic chains, exhibited IC50 values in the micromolar range.


Asunto(s)
Antineoplásicos/síntesis química , Alcoholes Grasos/síntesis química , Antineoplásicos/farmacología , Diinos , Ensayos de Selección de Medicamentos Antitumorales , Alcoholes Grasos/farmacología , Humanos , Plantas Medicinales/química , Células Tumorales Cultivadas
16.
Planta Med ; 66(2): 176-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10763596

RESUMEN

The crude chloroform bark extract of Syncarpia glomulifera (Myrtaceae) shows antibacterial and cytotoxic activity. Bioactivity-directed separation led to the isolation of oleanolic acid-3-acetate, ursolic acid-3-acetate and betulinic acid. The relatively large abundance (10% of the crude extract) and high degree of activity of betulinic acid are responsible for the bioactivity of the crude bark extract.


Asunto(s)
Extractos Vegetales/farmacología , Plantas Medicinales/química , Triterpenos/farmacología , Antiinfecciosos/farmacología , Antineoplásicos Fitogénicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Triterpenos/química , Células Tumorales Cultivadas
17.
Fitoterapia ; 71(2): 195-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10727820

RESUMEN

A phytochemical investigation of the chloroform leaf extract of Alchornea latifolia has been undertaken. Along with the triterpenoids taraxerone, friedelin, epifriedelinol, and taraxerol, the plant also contains seco-3,4-friedelin (dihydroputranjivic acid) (1) and seco-3,4-taraxerone (2). These A-ring-opened triterpenoids show in vitro cytotoxic activity against Hep-G2 and A-431 human cancer cell lines and are potent inhibitors of topoisomerase II.


Asunto(s)
Euphorbiaceae , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacología , Plantas Medicinales , Triterpenos/farmacología , Humanos , Medicinas Tradicionales Africanas , Pruebas de Sensibilidad Microbiana , Ácido Oleanólico/química , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta , Staphylococcus aureus/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Triterpenos/química , Células Tumorales Cultivadas/efectos de los fármacos
18.
Planta Med ; 65(5): 468-9, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10418341

RESUMEN

The leaf essential oil of an undescribed species of Myrcianthes has been obtained from Monteverde, Costa Rica. The essential oil exhibits in vitro cytotoxic activity against Hep-G2 and SK-Mel-28 human tumor cell lines. A GC/MS analysis shows the essential oil to be composed of 2-heptanol, alpha-pinene, beta-pinene, limonene, cineole, and alpha-terpineol, alpha-Pinene, beta-pinene, and limonene account for the cytotoxic activity of the leaf essential oil of Myrcianthes sp. nov. "black fruit".


Asunto(s)
Aceites Volátiles/toxicidad , Árboles , Animales , Artemia/efectos de los fármacos , Costa Rica , Humanos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Hojas de la Planta , Relación Estructura-Actividad , Células Tumorales Cultivadas
19.
Planta Med ; 65(8): 747-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10630119

RESUMEN

The crude chloroform bark extract of Piper caninum (Piperaceae) exhibits antibacterial activity against the Gram-positive bacteria, Bacillus cereus, Staphylococcus aureus, and Streptococcus pneumoniae. The antibacterial agents in this extract have been isolated using bioactivity-directed chromatographic techniques and identified by NMR spectroscopy as (+)-bornyl p-coumarate and bornyl caffeate. A single-crystal X-ray structure has been carried out on (+)-bornyl p-coumarate. The compound crystallizes in the orthorhombic space group P2(1)2(1)2(1) (#19) with a = 12.659(4), b = 13.281(4), and c = 10.177(3) A. Fullmatrix least-squares refinement converged at R = 0.047, and Rw = 0.058.


Asunto(s)
Antibacterianos/química , Ácidos Cumáricos/química , Plantas Medicinales/química , Ésteres , Modelos Moleculares , Estructura Molecular
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