Química
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Photochemische Umlagerung von 1-Acyloxy-1-alkoxy-λ5-phosphorin-Derivaten
(1976)Während bei 1-Akoxy-1-benzoyloxy-2,4,6-triphenyl-λ5-phosphorin-Derivaten 1a-e photochemisch in Ausbeuten von 46 - 96% dieselben 1-Alkoxy-6c-benzoyl-1r-oxo-2,4,6-triphenyl-1λ5-phospha-2,4-cyclohexadiene 2a-e isoliert werden, ... -
Derivados del 3,4-Dihidro-isoazol
(1978)Synthesis and structure elucidation of the products (3a-e) of condensation of phenanthrenequinone with various ketones in presence of ammonia. -
Residuos, degradación y comportamiento de la ametrina en un vertisol de Guanacaste. Costa Rica
(1978)Residues of the herbicide Ametrine (2-ethylamine-4-isopropylamine-6-methylthio-s-atrazine) were determined by UV-spectrometrical analysis in a soil (vertisol) of Guanacaste, Costa Rica, which has been treated with this ... -
Reacción del Oxido de Etileno con Clorhidratos de Aminoácidos
(1978)Se estudió la reacción del óxido de etileno con clorhidratos de aminoácidos a bajas temperaturas. Esta reacción conduce a la obtención de los aminoácidos libres. Se probó la eficiencia de este nuevo método de purificación ... -
Derivados del fenantreno [9,10-d] Imidazol
(1981)A simplified synthetic method of the phenanthro[9,10-d]imidazol (1) is reported in this work. The acetyl derivative (2) and a new cupric complex (3) of the imidazole (1) are synthesized, and the structures assigned on the ... -
Espectro de Masas de Algunos Derivados del 9,10-Dihidrofenantreno
(1978)Discussion of the mechanisms of mass spectra fragmentation of some derivatives of 9,10-dihidrofenantreno -
Estructura y Configuración de la Diacetona-Fenantrenoquinona
(1981)Estudio de la estructura y configuración molecular de la diacetona-fenantrenoquinona por difracción de rayos X y espectrometría de masas -
Esteres mixtos derivados del trans-9,10-dihidroxi-9,10-dihidrofenantreno
(1982)Synthesis, structure elucidation, steric effects, and spectrometric analysis of some mixed esters of trans-9,10-dihydroxy-9,10-dihydrophenanthrene are discussed. The quasi-axial conformation of the two ester groups, in ... -
Residuos, Degradación y Persistencia del Fungicida Maneb en Patatas en Costa Rica
(1983)Residues of the fungicide maneb (manganese-1,2-ethylen-bisdithiocarbamate) were analyzed by the carbondisulfide evolution method in samples of potatoes, potato leaves and soil from a commercial crop located in Llano Grande ... -
Fundamentos de Química Orgánica
(1985)Este libro es una introducción a la Química Orgánica, para estudiantes de carreras médicas, Microbiología, Biología, Agricultura, Veterinaria. Llena un vacío entre textos escolares y libros de texto de la carrera de Química. -
Análisis de Plaguicidas Organoclorados en Grasa Humana en Población Costarricense sin Riesgo Ocupacional
(2005-06-09)Se estudió el contenido de residuos de plaguicidas organoclorados y otros hidrocarburos clorados en tejido adiposo de costarricenses de ambos sexos (25 hombres y 26 mujeres). Las muestras fueron tomadas durante intervenciones ... -
Fevicordin A and Fevicordin A Glucoside, Novel Norcucurbitacins from Fevillea cordifolia
(1987)From the seeds of the Central American Fevillea cordifolia (Cucurbitaceae) fevicordin A glucoside (1) and fevicordin A (2) members of the novel norcucurbitacin group, were isolated. -
Gaschromatographische Analyse des Samenfettes der mittelamerikanischen Fevillea Cordifolia (Cucurbitaceae)
(1992)The fat of the seeds of Fevillea cordifolia was extracted under exclusion of oxygen and light and then characterized by 13C-NMR in regard to the contained unsaturated acid moieties. The total fat was separated by HPLC to ... -
Sub‑micron patterning of metal oxide surfaces via microcontact printing and microtransfer molding of amphiphilic molecules and antifouling application
(2023)Low cost, potentially scalable soft lithography approaches are employed here to generate nano and microscale line patterns of n-octadecylphosphonic acid and n-octadecyltriethoxysilane with thicknesses ranging from 2 up ... -
Validación de un método para cuantificación de acetaminofén en tabletas de 500 mg por espectrofotometría ultravioleta para la prueba de uniformidad de contenido
(2016-07-07)El presente artículo contiene los detalles de la validación del método analítico para la cuantificación de acetaminofén, en este caso para aplicar a la prueba de uniformidad de contenido a tabletas de 500 mg, por la técnica ... -
Síntesis de la feromona sexual de la polilla de la papa, Scrobipalpopsis Solanivora
(1988)Se sintetizó el acetato (E) -3- dodecenilo, atrayente sexual de la polilla de la papa (Scrobipalpopsis solanivora), utilizando dos procedimientos: una ruta acetilénica y mediante la condensación de Knoevenagel. -
Regiospecific Palladium-Catalyzed Cross-Coupling Reactions Using the Operational Equivalent of 1,3-Dilithiopropyne
(2020)A regiospecific palladium-catalyzed cross-coupling reaction using the operational equivalent of the dianion 1,3-dilithiopropyne, with aromatic iodides is reported. This reaction gives high yields of 1-propyn-1-yl-benzenes ... -
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 ... -
A new and efficient synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone component of the tomato leafminer Tuta absoluta
(2018)An efficient synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone component of the tomato leafminer moth, Tuta absoluta, was accomplished. The synthesis started with but-3-yn-1-ol and gave an ... -
Synthesis of N-[3-(prop-1-yn-1-yl)phenyl] benzene sulfonamide and Determination of its Antibacterial Activity
(2019-07-25)The synthesis of N-[3-(prop-1-yn-1-yl)phenyl] benzenesulfonamide was performed and its antibacterial activity against Staphylococcus aureus and Escherichia coli was determined. Minimalinhibitory concentrations (MIC) of ...
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