Ethanaminide → Trifluoroacetate

Participants

Reaction Steps

The procedure described in Example 1 can used but substituting Fmoc-Arg(Pbf)-[4-(4-N-isopropyl)methyl-3-methoxyphenoxy]butyryl AM resin for Fmoc-Pro Sieber ethylamide resin and omitting the coupling with Fmoc-Arg(Pmc). Upon completion of the synthesis the peptide can be cleaved from the resin using a mixture of (95:2.5:2.5) TFA/anisole/water for 3 hr. The peptide solution can be concentrated in vacuo and then precipitated with diethyl ether. The crude peptide can be purified by HPLC using C-18 column and with a solvent mixture varying over 50 minutes in a gradient from 5% to 100% acetonitrile-water containing 0.01% TFA. The pure fractions can be lyophilized to give N-Ac-Ile-Arg-NHCH(CH3)2 as trifluoroacetate salt.

Provenance & Evidence