The reaction of alcoholates with esters of perfluoroalkylethanoic acid (I) and 3-perfluoroalkyl-3-fluoro-propenoic acid (II) has been studied. Formation of ethers of the enol ester III or the acetal IV depends on the stoichiometric conditions used. The formation of the products proceeds via a Michael-type addition and elimination of fluoride ions from the enolate formed as an intermediate.
Methidium intercalator inserted into synthetic oligonucleotides
作者:Edward N. Timofeev、Igor P. Smirnov、Lawrence A. Haff、Ekaterina I. Tishchenko、Andrei D. Mirzabekov、Vladimir L. Florentiev
DOI:10.1016/0040-4039(96)01968-5
日期:1996.11
A new methidiumintercalator phosphoramidite has been synthesized. Methidium incorporation into an oligonucleotide during the synthesis was confirmed by UV and MALDI TOF MS data. UV melting experiments showed enhanced stability of a duplex, containing internal methidium.
Nucleophilic Substitution Reaction of 5-t-Butyl-2-methoxy-3H-azepine with Alkoxides and Alkyllithium Reagents: A Formation of Bis(5-t-butyl-3H-azepin-2-yl)methane Having a Vinamidine Conjugation
Reaction of 5-t-butyl-2-methoxy-3H-azepine (2) with nuclephiles (alkoxides or t-butyllithium) gave respective substitution product at 2-position of the ring. Unexpectedly, when methyllithium was used as a nucleophile, bis(5-t-butyl-3H-azepin-2-yl)methane (7), the structure of which found to be tautomeric vinamidine (7a,b), was formed. Tautomerization between 7 and 7a,b was characterized spectroscopically and theoretically based on the levels of B3LYP/631G(d).