Elvia Cabrera - Academia.edu (original) (raw)

Papers by Elvia Cabrera

Organic Preparations and Procedures International

Journal of Chemical Research Synopses, 2010

Journal of Chemical Research Synopses, Jun 1, 2003

ABSTRACT A concise synthesis of the enone (11), a potential intermediate for (±)-forskolin (12) s... more ABSTRACT A concise synthesis of the enone (11), a potential intermediate for (±)-forskolin (12) synthesis is described.

Journal of Scientific Industrial Research, May 1, 2006

ABSTRACT Commercially available iodine has played an important role in organic synthesis. This re... more ABSTRACT Commercially available iodine has played an important role in organic synthesis. This review discusses the versatile uses of iodine in different chemical transformations. Reactions include esterification, cycloaddition reaction, allylation of aldehydes, acetalization of carbonyl compounds, acylation of alcohols, synthesis of cyclic ethers and aromatization of α,β-unsaturated ketones. Introduction Selective functional group transformation of complex molecules to target compounds is the most important requirements of modern organic synthesis. The lack of selectivity blocks the road for obtaining the desired compounds. Iodine, commercially available brown solid, m p 113 o C, has found widespread use not only in conduction of selective transformation but also shown interesting and varied reactions. The present review concentrates on the utility of iodine in certain organic transformations, excluding iodolac-tonization and iodocyclization studies 1-5. Synthesis of Benzodiazepine Derivatives Synthesis of 1,5-benzodiazepine derivatives from phenyldiamines and acyclic ketones under mild conditions in presence of iodine as catalyst has been reported 6. O-Phenyldiamine 1 with acyclic ketone 2 and cyclic ketone 3 yields benzodiazepines 4 and 5 respectively (Scheme I). Such synthesis can also be accomplished in presence of other catalysts (boron trifluoride etherate, sodium borohydride, polyphos-phoric acid, silicon dioxide, etc.) but these procedures suffer from drastic reaction conditions, low to moderate yield and occurrence of several side reactions. Iodine helps to carry out reactions under neutral and mild condition and in high yield. In addition, work-up procedure is very simple and reaction can be performed at room temperature. Esterification and Transesterification Iodine has been utilized as Lewis acid catalyst for esterification 7 of acids (saturated, unsaturated, hy-droxy and dicarboxylic acids) with alcohols. Thus, conversion of acids 6-7 to corresponding esters 8-9 has been accomplished in high yield by heating with methanol at refluxing temperature (Scheme II). Esters of tertiary alcohols, which are difficult to prepare, can be obtained by heating the acid with t-butanol but it requires longer reaction period and increased amount of catalyst. The carboxylic acid group, directly attached to aromatic ring such as benzoic acid, p-nitrobenzoic acid, can not be esterified.

Resumen En las últimas décadas son muchos los compuestos con actividad dopaminérgica central que ... more Resumen En las últimas décadas son muchos los compuestos con actividad dopaminérgica central que se han diseñado, sin-tetizado y evaluado farmacológicamente, incluyendo a los análogos N-sustituidos del 2-aminoindano y de las 2-ami-notetralinas. A pesar de ello, no se ha logrado obtener un fármaco capaz de mejorar o curar las patologías que in volucran la regulación dopaminérgica en el sistema nervioso central, tales como el mal de Parkinson y la esquizo-frenia, entre otras. En el presente trabajo se planteó el diseño y síntesis de un nuevo compuesto basado en el siste-ma N-aralquílamino-metiladamantano no reportado en la literatura y aplicando como paso clave la reacción de sustitución nucleofílica radicalaria unimolecular (S RN 1). Asimismo, se evaluó el perfil de su acción dopaminérgica mediante la determinación de parámetros conductuales en ratas. Los resultados de la evaluación farmacológica pre-liminar muestran que el compuesto 9 se comporta como un agonista dopaminérgico centr...

Organic Preparations and Procedures International, 2015

Organic Preparations and Procedures International, 2014

ChemInform, 1999

Total Synthesis of (±)-Veadeiroic Acid.-Title compound (IX), a diterpene possessing the rare clei... more Total Synthesis of (±)-Veadeiroic Acid.-Title compound (IX), a diterpene possessing the rare cleistanthane skeleton, is prepared from phenol derivative (I) using Nagata's method for introducing a hydroxymethylene group at the ortho position of phenols as the key step (some yields not given).-(BANERJEE,

Revista de la Facultad …, 2011

Journal of Water Supply: Research and Technology—AQUA, 2009

ABSTRACT The importance of performance assessment in the water industry is demonstrated by the in... more ABSTRACT The importance of performance assessment in the water industry is demonstrated by the increasing number of initiatives taking place around the world. Since the first initiatives, which started 15 years ago, the topic has evolved significantly although it still presents challenges to be tackled. Five years ago, a project on performance assessment of urban infrastructure services was submitted to the European Union under the COST programme. As a consequence, the COST C18 Action was created. This paper presents the main conclusions and future key research areas from the project. In the solid waste sector, existing practical experience is less advanced, but methodologies and conclusions will be equally applicable in performance assessment projects.

Journal of Chemical Research, 2010

ABSTRACT

Current Organic Chemistry, 2011

Organic Preparations and Procedures International, 2012

Organic Preparations and Procedures International, 2011