We constructed a minilibrary using a solution-phase synthesis through coupling of three core amino compounds (5′-amino-5′-deoxy uridine, 5′-amino-2′,5′-di-deoxy arabinosyl uridine, and butan-1-amine) with 30 carboxylic acids via amide bond formation. The simplified structural core compound butan-1-amine was selectively coupled with 9 carboxylic acids as control. 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay of the crude mixtures showed that analogues derived from fenbufen, butylfenbufen C15; ethacrynic acid, butyl ethacrynic amide C18; and sphingosines, Sph-1, Sph-2 and U27 had an increased cytotoxicity against MCF-7 cells as well as A549 cells. Structural elucidation with molecular docking suggested that cytotoxicity of these compounds is mainly due to the inhibition of enzymes regulating cellular apoptosis.
Ethyl 2-(<i>tert</i>-Butoxycarbonyloxyimino)-2-cyanoacetate (Boc-Oxyma) as Coupling Reagent for Racemization-Free Esterification, Thioesterification, Amidation and Peptide Synthesis
the synthesis and utility of ethyl2-(tert-butoxycarbonyloxyimino)-2-cyanoacetate (Boc-Oxyma) as an efficient coupling reagent for racemization-free esterification, thioesterification, amidation reactions and peptide synthesis that uses equimolar amounts of acids and alcohols, thiols, amines or amino acids, respectively. Its application to solid phase as well as solution phase peptide synthesis is also
Direct Transformation of Secondary Amides into Secondary Amines: Triflic Anhydride Activated Reductive Alkylation
作者:Kai-Jiong Xiao、Ai-E Wang、Pei-Qiang Huang
DOI:10.1002/anie.201204098
日期:2012.8.13
transformation has been developed (see scheme; 2‐F‐Py=2‐fluoropyridine; Tf=trifluorosulfonyl). The amines are synthesized in good yields and the ketimine intermediates can be isolated before the reduction. This method should find applications in the synthesis of nitrogen‐containing bioactive molecules and medicinal agents.
Scratch the surface: Dehydrocondensations between carboxylates and amines by using an amphiphilic 1,3,5‐triazinylammonium‐based coupling agent were accelerated by the interfacial effect of micelles and emulsions of commonsurfactants (see figure). The reaction of carboxylates was promoted by both anionic and nonionic surfactants, and that of amines was promoted by only a nonionic surfactant. High selectivities