Ciencias básicas
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Recent Submissions
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Synthesis and preliminary determination of antibacterial activity of some 1,3-enynes
(2019)The synthesis of five 1,3-enynes was performed and its activity against Gram-positive and Gram-negative bacteria was determined. -
Antimicrobial activity of sodium carboxylates against arcobacter sp. y campylobacter Sp.
(2019)Arcobacter and Campylobacter genres are pathogenic microorganisms associated with gastrointestinal diseases and their main transmission route is through food and water. Both genres have been strongly associated to poultry, ... -
5,5-Diphenyl-cis-penta-2,4-dienoic acid
(2019)In the title compound, C17H14O2, the dihedral angle between the phenyl rings is 76.52 (7)°. In the crystal, pairwise O—H⋯O hydrogen bonds link the molecules into carboxylic acid inversion dimers. -
N-[3-(Prop-1-yn-1-yl)phenyl]benzenesulfonamide
(2019)In the title sulfanilamide derivative, C15H13NO2S, which shows significant activity against Staphylococcus aureus and Escherichia coli, the dihedral angle between the planes of the aromatic rings is 62.15 (19)° and the ... -
A Facile Method for the Titration of Organolithium Reagents using Naphtylamine or Naphtylmethylamine as Indicators
(2019)A simple method for the titration of alkyllithiums with sec-butanol, using naphtylamine or naphtylmethylamine as color indicator, is reported. Both amines gave sharp-end points, easily determined by color changes from ... -
One-Pot Conversion of Aldehydes and Ketones into 1-Substituted and 1,4-Disubstituted 1,3-Enynes
(2018)Sequential treatment of 2,3-dichloropropene with magnesium and n-BuLi generates the operational equivalent of 1,3-dilithiopropyne, which upon treatment with aldehydes or ketones, produces the corresponding alkoxy lithium ... -
Synthesis and Biological Activity of New Antifungal Compounds: A Preliminary Study
(2018)In the present study, we synthesized three 1,3-enynes from their corresponding aldehydes. They exhibited antifungal activity, which was evaluated against Trichophyton rubrum, the most common dermatophyte responsible for ... -
Description of the nest and eggs of the green thorntail (discosura conversii)
(2016-06-15)The breeding biology of the genus Discosura (Trochilidae) is poorly known. Here, we describe in detail the nest and eggs of the Green Thorntail (D. conversii). We analyze two nests; one was collected with two eggs at Limón ... -
A facile method for the preparation of bishomopropargylic alcohols from acyl chlorides
(2014)Controlled dilithiation of propargyl bromide with two equivalents of n-butyllithium, in the presence of TMEDA, produces the operational equivalent of the dianion 1,3-dilithiopropyne. The latter reacts efficiently with ... -
Nueva síntesis de la feromona sexual de la polilla del repollo Plutella Xylostella
(2007)El compuesto (Z)-11-hexadecenal, feromona sexual de la polilla Plutella xylostella, fue preparado mediante tres secuencias sintéticas. La primer secuencia consistió de siete pasos y un rendimiento total de 47%. En las otras ... -
Synthesis and Determination of Antitumor Activity of Jacaranone and Synthetic Analogs
(2018)Natural product jacaranone, 1, and three analog derivatives were synthesized and their apoptotic and necrotic activity against four cancer cell lines was tested. One of these derivatives 7, was more active than the natural ... -
Nuevos métodos de preparación del 1,3-Dilitiopropino y sus aplicaciones en la síntesis de compuestos bioactivos
(2006)Se desarrolló un método para la preparación del 1,3-dilitiopropino, a partir de bromuro de propargilo. Este procedimiento ha sido usado para desarrollar nuevos métodos de síntesis de alcoholes homopropargílicos, 1,5-diinos, ... -
Stereospecific Synthesis of (E, Z)- and (Z, Z)-Hexadeca-10,12-dienal. Sex Pheromone Components of Diaphania hyalinata
(1998)Isomeric (E,Z)- and (Z,Z)-hexadeca-10,12-dienal were prepared, stereospecifically, in 51% and 43% overall yields from dec-1-yne. -
Propargylation of Carbonyl Compounds: An Efficient Method for the Synthesis of Homopropargyl Alcohols
(1998)Controlled dilithiation of allene, with two equivalents of n-butytlithium, produces the propargyl dianion 5. The latter couple efficiently with carbonyl compounds to produce homopropargyl alcohols in high yields. -
Biological and dosimetric evaluation of [11C]S-adenosyl methionine as a potential agent for prostate cancer diagnosis
(2018)Introduction: [11C]Choline ([11C]COL) has been widely used for prostate cancer diagnosis; however, this radiopharmaceutical is not recommended for patients with a low absolute PSA value (< 1 ng/mL) due to its limited ... -
The 2022 Seismic Hazard Model for Costa Rica
(2023-02)Costa Rica is located at the boundary of four tectonic plates where the regularity of destruc tive earthquakes highlights the necessity of seismic hazard estimations. This study contains the most recent Probabilistic ... -
Sismicidad localizada por la Red Sismológica Nacional durante el 2022
(2023-02-10)Durante el año 2022, la Red Sismológica Nacional (RSN) localizó 4763 sismos locales, lo cual equivale a la energía sísmica liberada por un terremoto de magnitud momento (Mw) 7,0. Los epicentros se concentraron principalmente ... -
Effect of El Niño and La Niña on abundance of frugivorous and nectarivorous terrestrial birds in three tropical forests
(2019-05-14)El Niño and La Niña climatic oscillations have dramatic effects on population dynamics and community structure of different animals. For marine birds, El Niño phenomenon drastically increases their mortality and reduces ... -
Definición de los servicios ecosistémicos, su valoración económica y su afectación por el cambio climático
(2023-02-22)Se presentan cinco infografías relacionadas con la definición de los servicios ecosistémicos, su valoración económica y su afectación por el cambio climático. Se muestran también algunos de los servicios ecosistémicos de ...
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