2,303 research outputs found
Quercetina 3-metileter de las hojas de phoebe cinnamomifolia
Investigaciones químicas de especies pertenecientes al géntro Phoebe, reportan el aislamiento de alcaloides aporfínicos y oxoaporfínicos (1). Phoebe cinnamomifolia es una especie arbórea de las regiones Andina y Amazónica de Colombia; de su corteza se aislaron e identificaron (-) epicatequina; proantocianidina B2; pVoantocianidina B4 y a-farneseno (2) y de la madera 1,2,3,9,10-entametoxioxoaporfina; 1,2,9,10-tetrametoxioxoaporfina; sitosterol; n-tetracosanol y los ácidos cáprico; oleico; behénico; araquídico y esteárico (1). Del extracto etanólico de las hojas de P. cinnamomifolia, se estudió el residuo insoluble en éter de petróleo-acetato de etilo (9:1) dando como compuesto mayoritario quercetina 3-metil éter 1 y alcaloides oxoaporfínicos no identificados
Nuevos aspectos de la reacción tipo mannich en medio básico de 1,3,6,8-tetrazatriciclo[4.4.1.13,8] dodecano (tatd) con fenoles
Se ensayaron algunos fenoles como nucleófilos en la reacción tipo Mannich en medio básico frente al aminal macrocíclico1,3,6,8-tetrazatriciclo[4.4.1.1 3,8] dodecano (TATD). Dependiendo del grado de sustitución del fenol empleado, se obtuvieron:1,3- bis- [2’- hidroxibencil] imidazolidinas regioselectivamente, 2,6-di[3’-(2’’-hidroxibencil)-1’-metilenimidazolidin] fenoles y 3,3’-etilen-bis-(3,4-dihidro-2H- 1,3-benzoxazinas)
Absolute Configuration by Vibrational Circular Dichroism of Anti-inflammatory Macrolide Briarane Diterpenoids From the Gorgonian Briareum Asbestinum
[Abstract] The four new briarane diterpenoids 2-butyryloxybriarane B-3 (2), 9-acetylbriarenolide S (3), briarenolide W (4), and 12-isobriarenolide P (5), along with briarane B-3 (1) and the five known diterpenes 6–10 were isolated from the gorgonian coral Briareum asbestinum collected from the Mexican Caribbean Sea. The structures were elucidated by 1D and 2D NMR and MS measurements. Since the structure of briarane B-3 (1) was only suggested and published without any spectroscopic support, it was herein confirmed, and the supporting data are now provided. In addition, 1 provided the opportunity to explore the sensitivity of vibrational circular dichroism (VCD) to determine the configuration of a single stereogenic center in the presence of eight other stereogenic centers in a molecule possessing a highly flexible ten-member ring. A single-crystal X-ray diffraction study, in which the Flack and Hooft parameters of 1 were determined, further confirmed that briarane B-3 is (1S,2S,6S,7R,8R,9S,10S,11R,17R)-1. This paper reports for first time the use of VCD in briarane diterpenes and with the presence of chlorine atoms. Biological evaluation of seven isolated compounds evidenced a moderate anti-inflammatory activity for compounds 6 and 9 but it did not show any cytotoxic, antiviral, antibacterial, and topoisomerase inhibitory activity.This work was supported by Grants RTI2018-093634-B-C22 (AEI/FEDER, EU) from the State Agency for Research (AEI) of Spain, co-funded by the FEDER Programme from the European Union. We thank to Xunta de Galicia for the support of Grants GRC2018/039 and ED431E 2018/03 for CICA-INIBIC strategic group and BLUEBIOLAB (o474_BLUEBIOLAB_1_E, Programme INTERREG V A of Spain-Portugal (POCTEP). JR, CJ, and D.P.-P. acknowledge CESGA for the use of the computational facilities. PJ-N acknowledges partial financial support from CONACYT-Mexico Grant No. 284194. D.P.-P. received a postdoctoral fellowship from the National Council of Science and Technology (CONACYT) of Mexico. The work was also supported by UIDB/50006/2020 with funding from FCT/MCTES through national fundsXunta de Galicia; GRC2018/039Xunta de Galicia; ED431E 2018/03México. Consejo Nacional de Ciencia y Tecnología; 284194Portugal. Fundação para a Ciência e a Tecnologia; UIDB/50006/202
GC-FID-MS and X-ray Diffraction for the Detailed Evaluation of the Volatiles From Senecio filaginoides
The medicinal aromatic plant Senecio filaginoides DC, which is very widespread in the Patagonia region, was harvested at the vegetative, flowering, and fructification stages. The materials were extracted by hydrodistillation, yielding in average 0.34% v/w of essential oils with a pleasant sweet and greenish scent. A total of 56 components were identified by gas chromatography using flame ionization detection and mass spectra measurements, representing 96.1%-97.6% of the total oil. The sesquiterpenoid 10αH-furanoeremophil-1-one (1) appeared as a major constituent (16.2%-26.9%) of the oil. It could be isolated by cooling the oil at 4°C, thus yielding yellow crystalline solids. Its stereochemistry was assigned by single-crystal X-ray diffraction since previous studies identified the compound with different stereochemistries. The use of classical separation and analytical methodologies remains as a very useful strategy for the correct identification of compounds present in the volatile fraction of a plant and is a route for potential industrial applications.Fil: Van Baren, Catalina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: González, Silvia Beatriz. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Bandoni, Arnaldo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Di Leo Lira, Paola Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Bucio, María A.. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados. Departamento de Investigaciones Educativas.; MéxicoFil: Hernández Barragán, Angelina. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados. Departamento de Investigaciones Educativas.; MéxicoFil: Joseph Nathan, Pedro. Instituto Politécnico Nacional. Centro de Investigación y de Estudios Avanzados. Departamento de Investigaciones Educativas.; Méxic
Insecticidal activity of the petroleum ether extract of ageratum conyzoides l.
Se estableció que el extracto de éter de petróleo (pe 40-60"') de Ageratum conyzoides L. presenta fuerte actividad insecticida contra larvas de tercer estadio de Musca domestica (Díptera), contra larvas de tercer, cuarto y quinto estadio de Cynthia carye (Lepidoptera) y contra individuos adultos de Acanthoscelides obtectus (Coleóptera). En esta acción insecticida podrían estar involucrados dos flavonoides conocidos que se aislaron de este extracto: eupalestina y lucidina dimetiléter. También se aisló prococeno II, cromeno éste que demostró ser altamente tóxico contra larvas de M. domestica cuando las pruebas de contacto se hicieron irradiando con luz solar. En cambio, no mostró ningún efecto cuando los ensayos se hicieron en la oscuridad o bajo irradiación de luz UV
The Cosmology Large Angular Scale Surveyor
The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array
designed to characterize relic primordial gravitational waves from inflation
and the optical depth to reionization through a measurement of the polarized
cosmic microwave background (CMB) on the largest angular scales. The
frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one
dichroic system at 145/217 GHz, are chosen to avoid spectral regions of high
atmospheric emission and span the minimum of the polarized Galactic
foregrounds: synchrotron emission at lower frequencies and dust emission at
higher frequencies. Low-noise transition edge sensor detectors and a rapid
front-end polarization modulator provide a unique combination of high
sensitivity, stability, and control of systematics. The CLASS site, at 5200 m
in the Chilean Atacama desert, allows for daily mapping of up to 70\% of the
sky and enables the characterization of CMB polarization at the largest angular
scales. Using this combination of a broad frequency range, large sky coverage,
control over systematics, and high sensitivity, CLASS will observe the
reionization and recombination peaks of the CMB E- and B-mode power spectra.
CLASS will make a cosmic variance limited measurement of the optical depth to
reionization and will measure or place upper limits on the tensor-to-scalar
ratio, , down to a level of 0.01 (95\% C.L.)
Control and systems software for the Cosmology Large Angular Scale Surveyor (CLASS)
The Cosmology Large Angular Scale Surveyor (CLASS) is an array of
polarization-sensitive millimeter wave telescopes that observes ~70% of the sky
at frequency bands centered near 40GHz, 90GHz, 150GHz, and 220GHz from the
Atacama desert of northern Chile. Here, we describe the architecture of the
software used to control the telescopes, acquire data from the various
instruments, schedule observations, monitor the status of the instruments and
observations, create archival data packages, and transfer data packages to
North America for analysis. The computer and network architecture of the CLASS
observing site is also briefly discussed. This software and architecture has
been in use since 2016, operating the telescopes day and night throughout the
year, and has proven successful in fulfilling its design goals.Comment: 19 pages, 8 figures, to appear in Proc. SPI
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An integrated clinical program and crowdsourcing strategy for genomic sequencing and Mendelian disease gene discovery.
Despite major progress in defining the genetic basis of Mendelian disorders, the molecular etiology of many cases remains unknown. Patients with these undiagnosed disorders often have complex presentations and require treatment by multiple health care specialists. Here, we describe an integrated clinical diagnostic and research program using whole-exome and whole-genome sequencing (WES/WGS) for Mendelian disease gene discovery. This program employs specific case ascertainment parameters, a WES/WGS computational analysis pipeline that is optimized for Mendelian disease gene discovery with variant callers tuned to specific inheritance modes, an interdisciplinary crowdsourcing strategy for genomic sequence analysis, matchmaking for additional cases, and integration of the findings regarding gene causality with the clinical management plan. The interdisciplinary gene discovery team includes clinical, computational, and experimental biomedical specialists who interact to identify the genetic etiology of the disease, and when so warranted, to devise improved or novel treatments for affected patients. This program effectively integrates the clinical and research missions of an academic medical center and affords both diagnostic and therapeutic options for patients suffering from genetic disease. It may therefore be germane to other academic medical institutions engaged in implementing genomic medicine programs
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