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Search Results: 1 - 10 of 6618 matches for " Socorro Meza-Reyes "
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Conformational and Configurational Analysis of (2R,3S,5R)-2,5- Dimethyltetrahydropyran-3-Carboxylic Acid
Rosa E. del Río,Rosa Santillán,Jesús Sandova-Ramírez,Socorro Meza-Reyes
Revista de la Sociedad Química de México , 2006,
Abstract: El presente trabajo describe el análisis conformacional y configuracional del ácido 2,5 dimetiltetrahidropirano-3-carboxílico empleando el programa ALTONA desarrollado por el grupo de Joseph-Nathan. El ácido piranocarboxílico fue preparado a partir del acetato de 23-etilidendiosgenina, mediante una serie de reacciones que involucran el rompimiento de la cadena lateral de la sapogenina en medio ácido.
Side-chain opening of steroidal sapogenins to form 22-oxocholestanic skeletons: An approach to analogues of the aglycone of the potent anticancer agent OSW-1
Fernández-Herrera, María A.;Sandoval-Ramírez, Jesús;Meza-Reyes, Socorro;Montiel-Smith, Sara;
Journal of the Mexican Chemical Society , 2009,
Abstract: the side-chain opening of 25r and 25s steroidal sapogenins to form 22-oxocholestanic skeletons is described. the transformation was produced under mild conditions providing high yields (70-87%), in a one pot procedure (some acetylated starting material is recovered). this methodology yields 17-deoxy-26-oxy analogues of the aglycone of the potent anticancer agent osw-1. all products were fully characterized by 1d and 2d nmr; the most representative displacements are briefly discussed.
Westphalen's diol diacetate: 19(10→5)-abeo-5β-cholest-9-ene-3β,6β-diyl diacetate
Johana Ramírez Hernández,Jesús Sandoval-Ramírez,Socorro Meza-Reyes,José Luis Vega Báez
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812045278
Abstract: The structure of the title steroid [alternative name: 3β,6β-diacetoxy-5β-methyl-19-norcholest-9(10)-ene], C31H50O4, confirms the generally accepted mechanism for the rearrangement of a cholestan-5α-ol derivative reported a century ago by Westphalen. The methyl group at position 10 of the starting material migrates to position 5 in the steroidal nucleus, while a Δ9 bond is formed, as indicated by the C=C bond length of 1.347 (4) . The methyl transposition leaves the 5R configuration unchanged, with the methyl oriented towards the β face. During the rearrangement, the steroidal B ring experiences a conformational distortion from chair to envelope with the C atom at position 6 as the flap. In the title structure, the isopropyl group of the side chain is disordered over two positions, with occupancies of 0.733 (10) and 0.267 (10). The carbonyl O atom in the acetyl group at C3 is also disordered with an occupancy ratio of 0.62 (4):0.38 (4).
Side-chain opening of steroidal sapogenins to form 22-oxocholestanic skeletons. An approach to analogues of the aglycone of the potent anticancer agent OSW-1
María A. Fernández-Herrera,Jesús Sandoval-Ramírez,Socorro Meza-Reyes,Sara Montiel-Smith
Revista de la Sociedad Química de México , 2009,
Abstract: Se reporta la apertura de la cadena lateral de sapogeninas esteroidales 25R y 25S para obtener estructuras 22-oxocolestánicas. La transformación fue llevada a cabo bajo condiciones de reacción suaves y con altos rendimientos (70-87%), en un solo paso (se recupera materia prima acetilada). Con esta metodología se obtienen, en un solo paso, análogos 17-desoxi-26-oxigenados de la aglicona del potente anticancerígeno OSW-1. Todos los productos fueron caracterizados por RMN de una y dos dimensiones y los desplazamientos más representativos se discuten brevemente.
Motor Effects of 1,3-Disubstituted 8-Styrylxanthines as A1 and A2 Adenosine-Receptor Antagonists in Rats  [PDF]
Ilhuicamina Daniel Limón-Pérez de León, María del Carmen Parra-Cid, Alejandro Mu?oz-Zurita, Saúl Alejandro Merino-Contreras, Sara Montiel-Smith, Socorro Meza-Reyes, Gerardo Ramírez-Mejía, Jesús Sandoval-Ramírez
Pharmacology & Pharmacy (PP) , 2013, DOI: 10.4236/pp.2013.43044
Abstract:

A series of 1,3-substituted 8-styrylxanthines (11a-d) was synthesized, under chemo- and regioselective conditions, in a good overall yield. The compounds showed affinity towards both A1 and A2A-adenosine receptors by radioligand binding by means of in vitro assays. The (E)-3-ethyl-1-propyl-8-styrylxanthine (11a) showed the greatest affinity towards the A2A receptor, whereas (E)-3-pentyl-1-propyl-8-styrylxanthine (11d) showed the greatest affinity for the A1 receptor. When the 8-styrylxanthines 11a (A15Et) and 11c (A15Bu) were administrated in rats, which were previously injured with 6-hydroxydopamine at the substantia nigra pars compacta (SNc), the turning behavior decreased 50%. Based on these results we propose to A15Et as a potential compound to treat some symptoms of Parkinson’s disease.

Obtención de la (R)- y (S)-6-acetiloxi-5-metil-2,3-hexanodiona, ópticamente puras
Jesús Sandoval Ramírez,Socorro Meza Reyes,F. J. Meléndez,Guadalupe Hernández Linares
Revista de la Sociedad Química de México , 2001,
Abstract:
Obtención de la (R)- y (S)-6-acetiloxi-5-metil-2,3-hexanodiona, ópticamente puras
Jesús Sandoval Ramírez,Socorro Meza Reyes,F. J. Meléndez,Guadalupe Hernández Linares
Revista de la Sociedad Química de México , 2001,
Abstract: Se describe la síntesis enantioselectiva del novedoso par enantiomérico de las a-dicetonas-g-acetiladas 11 y 12 ópticamente puras, a partir de los compuestos (25S)-23-acetil-3b,26-diacetiloxi- 5b-furost-22-eno (7) y (25R)-23-acetil-3b,26-diacetiloxi-5a-furost- 22-en-12-ona (8), respectivamente, así como su caracterización espectroscópica.
Synthesis and Absolute Configuration of (20R)-20-Acetyl-23,24- bisnorcholanic Lactones Prepared from (E)-(20S,25R)- and (E)-(20S,25S)- 20,23-Diacetylfurost-22-enes
Guadalupe Hernández Linares,Socorro Meza Reyes,Sara Montiel Smith,Jesús Sandoval Ramírez
Revista de la Sociedad Química de México , 2007,
Abstract: Se reporta la síntesis de lactonas (20R)-20-acetil-23,24- bisnorcolánicas a partir de (E)-(20S,25R)- y (E)-(20S,25R)-(E)-20,23- diacetilfurost-22-enos (obtenidos a partir de diosgenina, hecogenina y sarsasapogenina). La configuración del centro estereogénico C-20 fue determinada por estudios de RMN y difracción de rayos X de monocristal. Las lactonas pueden ser usadas en la síntesis de una variedad de derivados esteroidales.
(E)-(25S)-23-Acetyl-5β-furost-22-ene-3β,26-diol
María-Guadalupe Hernández Linares,Jesús Sandoval Ramírez,Socorro Meza Reyes,Sara Montiel Smith
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808004509
Abstract: The title steroid, C29H46O4, is a furostene derivative with a C=C double-bond length of 1.353 (3) and an E configuration. The side chain is oriented toward the α face of the A–E steroidal nucleus and presents a disordered terminal CH2—OH group [occupancies for resolved sites are 0.591 (9) and 0.409 (9)]. The methyl group at C20 attached to ring E is also oriented toward the α face, avoiding steric hindrance with the carbonyl O atom of the acetyl group. The furostene and acetyl functionalities form an α,β-unsaturated ketone system, with an s-cis configuration. All hydroxy and carbonyl groups are involved in weak intermolecular hydrogen bonds. The absolute configuration was assigned from the synthesis.
The zwitterion (23′E)-(23R,25S)-23-[1-(oxidoiminio)ethyl]-5β-spirostan-3β-yl acetate
María-Guadalupe Hernández Linares,Jesús Sandoval Ramírez,Socorro Meza Reyes,Sara Montiel Smith
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809044651
Abstract: The title steroidal compound, C31H49NO5, resulted from the selective oximation of (23R)-23-acetylsarsasapogenin acetate. One- and two-dimensional 1H and 13C NMR spectra, as well as IR data, are in agreement with the presence of a ketoxime group at C-23. However, recrystallization in slightly acidic media affords the title compound in the rare zwitterionic oxime form, as a consequence of migration of the hydroxy H atom to the N atom in the oxime group. This H atom is clearly detected and its position was refined from X-ray data. The geometry for the C=N+(H)—O group features long C=N and short N—O bond lengths compared to non-zwitterionic oximes. The ketoxime is stabilized with the E configuration, avoiding steric hindrance between the oxime O atom and H atom at C-23. The sum of the angles around the oxime N atom is 359.6°, giving a planar configuration for that atom, as expected for sp2 hybridization.
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