25263-97-2Relevant academic research and scientific papers
Identification and synthesis of new sex-specific components of olive fruit fly (Bactrocera oleae) female rectal gland, through original Negishi reactions on supported catalysts
Fusini, Graziano,Barsanti, Davide,Angelici, Gaetano,Casotti, Gianluca,Canale, Angelo,Benelli, Giovanni,Lucchi, Andrea,Carpita, Adriano
supporting information, p. 4381 - 4389 (2018/07/21)
In the present study, eleven new sex-specific components extracted from female rectal gland of olive fruit flies were synthesized and identified. The quantitative determination of those components by GC and GC/EI-MS, at different moments of the insect life span, highlighted the growing trend of their secretion. While for the synthesis of saturated esters, conventional transesterification methods could be adopted, for the synthesis of unsaturated components, a Negishi cross-coupling between organozinc halides and (Z)-1-bromo-1-alkenes was developed. To the extent of our knowledge, this reaction represents the first example of supported-catalyst promoted Negishi coupling, between an alkylzinc reagent and an alkenyl halide.
Use of Lecitase-Ultra immobilized on styrene-divinylbenzene beads as catalyst of esterification reactions: Effects of ultrasounds
Alves, Joana S.,Garcia-Galan, Cristina,Danelli, Daiane,Paludo, Natália,Barbosa, Oveimar,Rodrigues, Rafael C.,Fernandez-Lafuente, Roberto
, p. 27 - 32 (2015/08/06)
Abstract In this work it was evaluated for the first time, the ester synthesis catalyzed by the phospholipase Lecitase-Ultra immobilized styrene-divinylbenzene beads (MCI-Lecitase), comparing the mechanical stirring and the ultrasonic energy. It was studied the specificity of the enzyme using carboxylic acids from C4 to C18, as well as the effects of alcohol chain, organic solvents, biocatalyst content, reaction temperature and substrate concentration. Caprylic and myristic acids were those with the highest reaction rates and yields, using ethanol as substrate. The shorter the alcohol chain, the higher the enzyme activity. Regarding the secondary alcohols, while MCI-Lecitase had no activity versus isopropanol, using 2-pentanol the activity was similar to that with 1-pentanol. Comparing the agitation systems, MCI-Lecitase presented an initial reaction rate more than 2-times higher in the ultrasound-assisted reaction than under traditional mechanical stirring. Moreover, under ultrasonic energy the maximum rate was achieved using 0.5 M of substrates, while under mechanical stirring the maximum enzyme activity was reached at 0.3 M of substrates. Concerning the operational stability, MCI-Lecitase was quite unstable, losing its activity after 6 reaction cycles. By adding molecular sieves in the reaction medium, MCI-Lecitase retained 30% of its initial activity after 6 cycles.
Design, synthesis, antibacterial, and QSAR studies of myristic acid derivatives
Narasimhan, Balasubramanian,Mourya, Vishnukant,Dhake, Avinash
, p. 3023 - 3029 (2008/09/20)
A series of esters and amides of myristic acid was synthesized and tested in vitro for antibacterial activity against Gram-positive and Gram-negative bacteria. All the compounds showed activity comparable to that of the standard drug, ciprofloxacin. The structural characteristics governing antibacterial activity of myristic acid derivatives was studied using QSAR methodology. The results showed that the antibacterial activity could be modeled using the topological descriptor, valence molecular connectivity index. The predictive ability of the models was cross-validated by construction of a test set. The low residual activity and high cross-validated r2 values ( rcv2 ) observed indicated the predictive ability of the developed QSAR models.
