Stereoselective synthesis and antitumoral activity of Z-enyne pseudoglycosides
作者:Claudio R. Dantas、Jucleiton J. R. de Freitas、Queila P. S. Barbosa、Gardenia C. G. Militão、Thiago D. S. Silva、Teresinha G. da Silva、Antônio A. S. Paulino、Juliano C. R. Freitas、Roberta A. Oliveira、Paulo H. Menezes
DOI:10.1039/c6ob00945j
日期:——
An efficient approach for the synthesis of Z-1,3-enynes based on the couplingreaction of Z-vinyl tellurides and alkynes containing a pseudoglycoside moiety is described. The products were obtained in good yields via a stereoselective way. Preliminary screening against three tumor cell lines indicated that the synthesized compounds are promising intermediates for the synthesis of an array of more potent
Differentiation and assignment of vinyl telluride regioisomers by <sup>1</sup>
H-<sup>125</sup>
Te <i>g</i>
HMBC
作者:Juliano C. R. Freitas、Dayvson J. Palmeira、Roberta A. Oliveira、Paulo H. Menezes、Ricardo O. Silva
DOI:10.1002/mrc.3826
日期:2012.7
Complete (1) H, (13) C, and (125) Te NMR spectral data for some vinyltellurides are described. The (1) H-(125) Te gHMBC experiment was used for the complete chemical shift assignment and structure elucidation of a mixture of regioisomers. The assignment ((125) Te NMR) and coupling constants (J(H,H) ) for all regioisomers are described for the first time.
Influence of different protecting groups on the regioselectivity of the hydrotelluration reaction of hydroxy alkynes
作者:Juliana M. Oliveira、Dayvson J. Palmeira、João V. Comasseto、Paulo H. Menezes
DOI:10.1590/s0103-50532010000200024
日期:——
The influence of protecting groups on the synthesis of regio- and stereodefined vinyl tellurides derived from the reaction of BuTeNa and propargylic- or homo-propargylic alcohols showed that TIPS silyl ether is useful as a regiodirecting group. The application of the methodology to the synthesis of a fragment of (+/-)-Seselidiol, a natural product, demonstrated the applicability of the new methodology.