Synthesis of Nα-Tetrachlorophthaloyl (TCP)-Protected Amino Acids under Microwave Irradiation (MWI)
作者:Esther Cros、Marta Planas、Eduard Bardají
DOI:10.1055/s-2001-15215
日期:——
A range of N α-tetrachlorophthaloyl protected amino acids have been synthesized by an easy and efficient condensation procedure of the corresponding amino acid and tetrachlorophthaloyl anhydride under irradiation in an unmodified commercial microwave oven.
The N-tetrachlorophthaloyl-(TCP-)amino protecting group has been evaluated for use in solid-phasepeptidesynthesis. The TCP group was unaffected by exposure to either piperidine or N,N-diisopropylethylamine (DIEA), which suggests compatibility with both Fmoc and Boc solid-phasesynthesis protocols. Quantitative TCP removal was achieved by treatment with hydrazine/DMF (3:17) at 35 °C for 30 min or with
Transition-metal-catalyzed reaction of diazocompounds, efficient synthesis of functionalized ethers by carbene insertion into the hydroxylic bond of alcohols
An Efficient catalytic synthesis of unsaturated ethers by carbeneinsertion (with diazoesters as carbene precursors) into the OH bond of unsaturated alcohols is reported. The regioselectivity for the OH insertion is high. However, depending on the catalyst counter-ions and the diazoester alkoxy group, addition to the unsaturated centre can be promoted to some extent, yielding then cyclopropyl and cyclopropenyl
A new strategy for solid-phasesynthesis of C-terminal peptide amides based on the use of N-tetrachlorophthaloyl protected amino acids with acid-labile side-chain protection is described.