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- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/03%3A_Conformaciones_y_estereoquimica/3.12%3A_Problemas_para_el_Cap%C3%ADtulo_3P3.7: Las moléculas de abajo son nuevos fármacos potenciales para el tratamiento de distrofia muscular de Duchenne (molécula A) y cáncer de la piel (molécula B) (Chemical and Engineering News 26 de se...P3.7: Las moléculas de abajo son nuevos fármacos potenciales para el tratamiento de distrofia muscular de Duchenne (molécula A) y cáncer de la piel (molécula B) (Chemical and Engineering News 26 de septiembre del 2005, p.39). P3.9: Coelichelin (la estructura hacia abajo y a la izquierda) es un producto natural de las bacterias del suelo que fue identificado usando una técnica conocida como ‘minería genoma’ (Chemical and Engineering News 19 de septiembre del 2005, p.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/16%3A_Reacciones_de_oxidacion_y_reduccion/16.09%3A_Observando_el_progreso_de_las_reacciones_de_hidrogenacion_y_deshidrogenacion_por_ensayo_UVTherefore, the course of a hydrogenation reaction in which NAD(P)H is converted to NAD(P) + can be observed in real time if it is run in a quartz cuvette in a UV spectrometer. By observing the decreas...Therefore, the course of a hydrogenation reaction in which NAD(P)H is converted to NAD(P) + can be observed in real time if it is run in a quartz cuvette in a UV spectrometer. By observing the decrease in absorbance at 340 nm, the researcher can calculate how many moles of NAD(P)H has been oxidized at any given time point, and this number is equal to the number of moles of organic substrate that has been reduced.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/12%3A_Reacciones_de_sustitucion_de_acilo/12.8%3A_reacciones_de_sustituci%C3%B3n_de_acilo_con_un_carbono_o_hidruro_nucle%C3%B3filoAlthough we have seen many different types of nucleophilic acyl substitutions in this chapter, we have not yet encountered a reaction in which the incoming nucleophile is a carbanion or a hydride. Rec...Although we have seen many different types of nucleophilic acyl substitutions in this chapter, we have not yet encountered a reaction in which the incoming nucleophile is a carbanion or a hydride. Recall that in the previous chapter on aldehydes and ketones, we also postponed discussion of nucleophilic carbonyl addition reactions in which a carbanion or a hydride is the nucleophile.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/12%3A_Reacciones_de_sustitucion_de_acilo/12.7%3A_Grupos_de_amida_activadaNext, a kind of acyl substitution occurs that we have not yet seen: the amine nitrogen on the aspartate attacks the electrophilic carbon of a carbon-nitrogen double bond, and the reaction proceeds thr...Next, a kind of acyl substitution occurs that we have not yet seen: the amine nitrogen on the aspartate attacks the electrophilic carbon of a carbon-nitrogen double bond, and the reaction proceeds through a tetrahedral intermediate before the AMP group is expelled, taking with it what was originally the carbonyl oxygen of the starting amide.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/05%3A_Determinacion_de_estructura_parte_ll/5.8%3A_NMR_de_mol%C3%A9culas_fosforiladasIn the 13 C spectrum, notice that the signals for both C 1 and C 2 are split into doublets by the magnetic field of P A , through 2-bond and 3-bond coupling, respectively. Notice that although the C 1...In the 13 C spectrum, notice that the signals for both C 1 and C 2 are split into doublets by the magnetic field of P A , through 2-bond and 3-bond coupling, respectively. Notice that although the C 1 and C 2 signals were split by P A in our 13 C-NMR spectrum, in the 31 P-NMR spectrum the P A signal is not split by the nearby carbons - this is because, of course, both of these carbons are the NMR-inactive 12 C isotope in 99 out of 100 molecules.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/06%3A_Introduccion_a_la_reactividad_y_catalisis_organica/6.5%3A_Estructura_de_las_prote%C3%ADnasVirtually all of the amino acids found in proteins have the stereochemistry shown in the general figure above, and are referred to as L-amino acids ('L' stand for levorotary, the property of rotating ...Virtually all of the amino acids found in proteins have the stereochemistry shown in the general figure above, and are referred to as L-amino acids ('L' stand for levorotary, the property of rotating plane polarized light in a counter-clockwise direction).
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/16%3A_Reacciones_de_oxidacion_y_reduccion/16.04%3A_Fuera_de_la_caja_-_metanogenesisThe conversion of carbon dioxide into carbohydrates - the process of photosynthesis as carried out by plants - is an uphill thermodynamic process, with the energy provided by the sun. The reduction of...The conversion of carbon dioxide into carbohydrates - the process of photosynthesis as carried out by plants - is an uphill thermodynamic process, with the energy provided by the sun. The reduction of CO 2 to methane by hydrogen gas (H 2 ), for example, is a thermodynamically downhill process, because H 2 is a such a powerful reducing agent. When you see bubbles of 'swamp gas' (methane) rising from the mud of ponds and rivers, you are looking at the result of methanogenesis.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/15%3A_Reacciones_electrofilicas/15.05%3A_Sustituci%C3%B3n_arom%C3%A1tica_electrof%C3%ADlicaYet another example of a S N 1-like S E Ar reaction is found in the biosynthetic pathway for vitamin B 12 . The electrophile is generated by loss of ammonia (instead of pyrophosphate as in the previou...Yet another example of a S N 1-like S E Ar reaction is found in the biosynthetic pathway for vitamin B 12 . The electrophile is generated by loss of ammonia (instead of pyrophosphate as in the previous examples) from the first of two substituted aromatic rings:
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/13%3A_Reacciones_con_intermediados_de_carbaniones_estabilizados_I/13.4%3A_Reacciones_de_aldolAlternatively, the enolate carbon, which bears a degree of negative charge, could act as a base, which is simply the reverse of the initial deprotonation step that formed the enolate in the first plac...Alternatively, the enolate carbon, which bears a degree of negative charge, could act as a base, which is simply the reverse of the initial deprotonation step that formed the enolate in the first place. The enzyme-catalyzed reaction, not surprisingly, is completely stereospecific: the DHAP substrate is positioned in the active site so as to attack the re (front)face of the GAP carbonyl group, leading to the R configuration at the new stereocenter.
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/01%3A_Introduccion_a_la_estructura_y_union_organica%2C_parte_I/1.1%3A_Orbitales_at%C3%B3micos_y_configuraci%C3%B3n_de_electronesPara determinar la configuración de un electrón de un átomo, simplemente tienes que rellenar los orbitales con dos electrones cada uno, empezando con el de menos energía (1s) y continuando al de energ...Para determinar la configuración de un electrón de un átomo, simplemente tienes que rellenar los orbitales con dos electrones cada uno, empezando con el de menos energía (1s) y continuando al de energía más alta hasta que todos los electrones tengan un lugar en los orbitales (es posible que recuardes que esto se llama el principio de ‘aufbau’, o el principio de rellenar).
- https://espanol.libretexts.org/Quimica/Libro%3A_Qu%C3%ADmica_Org%C3%A1nica_con_%C3%A9nfasis_Biol%C3%B3gico_(Soderberg)/16%3A_Reacciones_de_oxidacion_y_reduccion/16.07%3A_Ejemplos_adicionales_de_reacciones_de_transferencia_de_hidruro_enzimaticasIn order to prevent the hydride transfer from proceeding, the researchers first hydrogenated the isolated C 2 -C 3 double bond on a sample of NADPH, using a palladium catalyst (under the conditions us...In order to prevent the hydride transfer from proceeding, the researchers first hydrogenated the isolated C 2 -C 3 double bond on a sample of NADPH, using a palladium catalyst (under the conditions used, the conjugated C 5 -C 6 double bond was left unreduced). The final step in the mechanism is where it gets really interesting: a hydride ion is transferred from the tetrahydrofolate coenzyme to the methylene (CH 2 ) group on the deoxynucleotide substrate.
