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Synthesis of 2-hydroxy-3-substituted naphthoquinones using the Heck reaction
(2007-06)
An efficient Heck coupling of 2-hydroxy-3-iodo-naphthoquinone with a series of electron-deficient alkenes in aqueous solution has been accomplished. The method is characterized by simple conditions and facile work-up to ...
A new methodology for the synthesis of δ-substituted α,β-unsaturated δ-lactones
(2020)
A new protocol for the synthesis of δ-substituted-α,β-unsaturated δ-lactones was developed. Selective reaction of 1,3-dilithiopropyne with ketones, followed by addition of ethyl chloroformate formed ethyl 5-[(ethoxycarbo ...
Biodegradation of Pharmaceuticals by Fungi and Metabolites Identification
(2012-01-01)
Pharmaceutical compounds comprise a widely employed group of
therapeutic agents now considered as emerging micropollutants. This chapter
summarizes the state of the art in the degradation of pharmaceuticals by fungi ...
Caracterización fisicoquímica de las aguas superficiales de la cuenca del río Rincón en la Península de Osa, Puntarenas, Costa Rica
(San Pedro de Montes de Oca, San José, Costa Rica, 2008)
Este proyecto se desarrolló en la cuenca del río Rincón en la península de Osa, una de las regiones
geológicas más antiguas de Costa Rica. En ella afloran unidades de roca ígnea y sedimentaria,
además de sedimentos ...
Synthesis and Antibacterial Activity of Aromatic Homopropargyl Alcohols
(2017)
Several aromatic homopropargyl alcohols, and derivatives were prepared by
one-pot reaction of 1,3-dilithiopropyne (or its equivalent) with aldehydes and
ketones. The antibacterial activity, of alcohols ...
Condensación de Cetonas Alifáticas con la Fenantrenoquinona en Hidróxido de Amonio
(1971)
A study on the synthesis and structure of the products of condensation of phenanthrenequinone with acetone and methyl-ethyl-ketone in presence of ammonia was
made. The structures were established by spectroscopic methods. ...
Guía de mediación pedagógica para aprendizajes comunitarios: comités de agua transfronte- rizos, Costa Rica - Nicaragua : pedagogía social, estrategias para la optimización del uso del agua para consumo humano en las comunidades de La Trocha e Isla Chica en los Chiles, Alajuela
(2021)
El equipo de profesores y profesoras de la Universidad Nacional y la Universidad de Costa Rica que elaboró esta guía conforma el proyecto de extensión y acción social universitaria: “Pedagogía social: estrategias para la ...
Rapid shift in microbial community structure in a neutral hydrothermal hot spring from Costa Rica
(2020)
In this work, we characterize the geochemistry and microbial community of Bajo las Peñas, a neutral (pH 6.5-7.4), hot spring (T = 62.0-68.0°C) located near Turrialba Volcano, Costa Rica. The microbiota at its two sources ...
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.