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Search Results: 1 - 10 of 355057 matches for " Jesús Sandoval-Ramírez "
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Extraction and Characterization of Oils from Three Mexican Jatropha Species
Maricela Rodríguez-Acosta,Jesús Sandoval-Ramírez,Reyna Zeferino-Díaz
Revista de la Sociedad Química de México , 2010,
Abstract: Se describe la composición de los aceites de semillas de tres especies de Jatropha endémicas de México. Los aceites fueron analizados a través de la formación de los ésteres metílicos y se encontró que sus rendimientos y composición guardan similitud al aceite de Jatropha curcas L. Los resultados muestran que las tres especies analizadas son fuentes potenciales para la producción de biocombustibles y por lo tanto son cultivos alternativos promisorios para la producción de biodiesel en las regiones áridas de México.
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.

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).
(25R)-6α-Hydroxy-5α-spirostan-3β-yl tosylate
María A. Fernández-Herrera,Jesús Sandoval-Ramírez,Sylvain Bernès,Maricela Rodríguez-Acosta
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812046600
Abstract: The title steroid, C34H50O6S, is an intermediate on the synthetic route between diosgenin and brassinosteroids, which possess the A ring modified with the 2α,3α-diol functionality. The polycyclic spirostan system has the expected conformation, with six-membered rings adopting chair forms and the five-membered rings envelope forms (flap atoms are the methine C atom in the C/D-ring junction and the spiro C atom connecting rings E and F). The 3β-tosylate group is oriented in such a way that S=O bonds are engaged in intermolecular hydrogen bonds with O—H and C—H donors. Chains of molecules are formed along [100] via O—H...O hydrogen bonds, and secondary weak C—H...O interactions connect two neighbouring chains in the [001] direction.
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.
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.
A convenient procedure for the synthesis of 3beta-hydroxy-6-oxo-5alpha-steroids: aplication to the synthesis of laxogenin
Iglesias-Arteaga, Martín A.;Símuta-Lopez, Eva M.;Xochihua-Moreno, Sergio;Vi?as-Bravo, Omar;Smith, Sara Montiel;Meza Reyes, Socorro;Sandoval-Ramírez, Jesús;
Journal of the Brazilian Chemical Society , 2005, DOI: 10.1590/S0103-50532005000300011
Abstract: a convenient pathway to obtain 3b-hydroxy-6-oxo-5a-steroids from 3b-acetoxy d5-steroids is reported; the methodology was applied to the synthesis of laxogenin (7), substance that behaves as a plant growth hormone. this is an alternative way to produce an important functionality found in many examples of naturally occurring steroids. the developed procedure uses inexpensive reagents and can be carried out in four steps. the oxidizing and acidic steps used in this methodology did not affect the labile spiroketal side chain present in diosgenin (16).
Association between polymorphisms of the androgen and vitamin D receptor genes with prostate cancer risk in a Mexican population
Patino-García, Brenda;Arroyo, Carlos;Rangel-Villalobos, Hector;Soto-Vega, Elena;Velarde-Félix, Jose Salvador;Gabilondo, Fernando;Sandoval-Ramírez, Lucila;Figuera, Luis Eduardo;
Revista de investigación clínica , 2007,
Abstract: introduction. prostate cancer (pca) is a worldwide health issue, because of its high incidence and mortality. its etiology is complex and includes certain risk factors such as age, hormonal status, ethnic origin and family history of pca. genetic predisposition is proposed as a major risk factor and there are several controversial reports on the association of pca and gene polymorphism such as the receptors of the androgen receptor (ar) and the vitamin d (vdr). objective. to evaluate the cag triplets repetitions in the first exon of the ar and polymorphisms in the restriction site taql in the vdr in mexicans with pca. material and methods. a total of 68 mexicans with histopathological diagnosis of pca and 48 healthy mexican with normal prostate specific antigen and rectal exam where included. 10ml of peripheral blood were extracted to isolate dna and the polymorphisms were evaluated with specific primers for the ar and vdr. results. the allelic and genetic distributions of the ar and vdr polymorphisms were consistent with the hardy-weinberg equilibrium, and there were no statistical differences between the pca patients and controls (p > 0.05). however, there was a statistical difference between the number of cag repeats in younger patients with pca compared to controls (p = 0.045) but when the young patient group was compared versus the elder group there was not stadistically difference (p = 0.085), but the results showed a tendency towards less repetitions of cag in elder patients. concerning the vdr, when we analyzed the patients with pca and a bad pathological prognosis they had a less frequent genotype of tt (p = 0.03). conclusions. our results suggest an association between the vdr and ar gene polymorphisms, and the hystopathological score and age at diagnosis in mexican patients with pca, respectively. however, it is important to confirm these results in a larger scale study.
Síntesis y evaluación del efecto ansiolítico de un nuevo derivado pirimido[1,6-a]pirimidínico
Alejandro Mu?oz Zurita,Jesús Sandoval Ramírez,Luis Emilio Espinoza Moreno,Carmen Parra Cid
Revista de la Sociedad Química de México , 2003,
Abstract: Se describe la síntesis de la (E)-9-estirilcarboxamido-6,8- dioxo-7-propil-1,3,4,6,7,8-hexahidro-2H-pirimido[1,6-a]pirimidina (9) a partir de 6-aminouracilo (4) utilizando una vía de síntesis quimio- y regioselectiva; además se reporta el estudio fármaco-biológico de 9 utilizando el modelo experimental ansiolítico del laberinto elevado en cruz. Adicionalmente, se presenta la relación dosis efecto de 9 sobre la actividad locomotora empleando el modelo de campo cerrado en ratas macho Wistar; la cual concluye que al administrar crónicamente diferentes dosis de 9 se genera un efecto ansiolítico importante y una disminución de la actividad locomotora.
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:
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