Abstract
A new polymer-supported urea (P-DMI) (4)
was prepared as a precursor for a new heterogeneous dehydrating
agent, polymer-supported chloroamidinium chloride (P-DMC) (5). Application of 4 to
esterification and amidation, after conversion to 5,
efficiently afforded dehydrated products. No epimerization was practically
observed in peptide synthesis. Compound 4 (P-DMI) was
recovered as a re-useable form by simple filtration.
Key words
polymer-supported reagent - esterification - amidation - peptide synthesis - recyclability
References
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