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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 ...
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. ...
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.
Desarrollo de sensores electroquímicos para la determinación de drogas sintéticas en fluidos biológicos y muestras de incautación
(2023-07-09)
La cantidad de nuevas sustancias psicoactivas, popularmente conocidas con términos como: drogas emergentes, drogas de diseño, drogas sintéticas o drogas recreativas, aumenta en el mercado global de las drogas cada año. El ...
β-Carboline monoterpenoid glucosides from Palicourea adusta
(1999)
Lyaloside, a monoterpenoid glucoindole alkaloid, was isolated from the leaves of Palicourea adusta together with a mixture of its hydroxycinnamic acid derivatives, (E)-O-(6′)-cinnamoyl-4″-hydroxy-3″-methoxy-lyaloside and ...
A New Method for the Preparation of 1-Ethynyl Ethers
(1994)
During our study of the stannylcupration of acetylenic
ethers we required [2-13C]-1 for mechanistic studies.
Existing methods for the synthesis of acetylenic ethers
involve dehydrohalogenation of 2-halo, ...