ACTIVATION OF DIKETOPIPERAZINE FORMATION BY ALKYLAMMONIUM CARBOXYLATESALTS AND APROTIC DIPOLAR PROTOPHOBIC SOLVENTS

Authors
CAPASSO S MAZZARELLA L
Citation
S. Capasso et L. Mazzarella, ACTIVATION OF DIKETOPIPERAZINE FORMATION BY ALKYLAMMONIUM CARBOXYLATESALTS AND APROTIC DIPOLAR PROTOPHOBIC SOLVENTS, Peptides, 19(2), 1998, pp. 389-391
Citations number
12
Categorie Soggetti
Biology
Journal title
Peptides → ACNP
ISSN journal
01969781
Volume
19
Issue
2
Year of publication
1998
Pages
389 - 391
Database
ISI
SICI code
0196-9781(1998)19:2<389:AODFBA>2.0.ZU;2-H
Abstract
Diketopiperazine formation from the N-terminal residues of a peptide c hain is accelerated by aprotic dipolar protophobic solvents and cataly zed in organic solvents by alkylammonium carboxylate salts. The t(1/2) for the first-order reaction of H-Ala-Pro-NH2 . TFA falls from 20 d i n methanol to 3.6 min in acetonitrile containing 0.02 mol dm(-3) triet hylammonium acetate; for H-Ala-Ala-NH2 . TFA in the same reaction medi a t(1/2) falls from an unmeasurably long time to 1.3 d. (C) 1998 Elsev ier Science Inc.