Solid-phase peptide synthesis using acetonitrile as a solvent in combination with PEG-based resins.

This manuscript shows that ACN can be an excellent choice for the coupling of hindered amino acids as illustrated by the coupling of Fmoc-amino acids on free amino acids anchored on a BAL synthesis. Furthermore, ACN can be a good alternative for solid-phase peptide synthesis in the absence of DMF (washings, removal of Fmoc, and coupling).

Combinatorial approaches towards the discovery of new tryptase inhibitors.

The synthesis and evaluation as tryptase inhibitors of a library of 2,5-diketopiperazine derivatives containing guanidine or amidine functional groups is reported. Among the compounds evaluated, derivatives 6{CG4-CG8} and 6{CG4-CG9} are the most active compounds and have marked selectivity towards tryptase in front of trypsin.