Synthesis and 1H-nmr studies of α-deuterated analogues of des-Trp1, Nle12-human minigastrin

✍ Scribed by Kitti Amonraksa; Mario Simonetti; Silvio Da Rin-Fioretto; Stefano Mammi; Evaristo Peggion

• Publisher: Wiley (John Wiley & Sons)
• Year: 1990
• Tongue: English
• Weight: 662 KB
• Volume: 30
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360300719

✦ Synopsis

Three analogues of the tridecapeptide amide H-Leu-( Glu) ,-Ala-Tyr-Gly-Nle-Asp-Phe-NH2 were synthetized with a-deuterated glutamate residues in specific positions in order to assign unambiguously the 'H nmr spectrum of the parent peptide in water and in watertrifluoroethanol mixtures. The synthetic route is described and the assignment illustrated. A previous, tentative assignment based solely on indirect evidence [ Mammi, S., Mammi, N. J. & Peggion, E. ( 1988) Biochemistry 27, 1374-13791 was partially modified.

EXPERIMENTAL

cording to Walsh et al.,7 and the numbering is different from our previous paper: The asterisk denotes a-deuteration sites.) Methods

In this paper we describe the synthetic route to The nmr spectra were recorded on a Bruker AM these materials and the results of 'H-nmr studies that allowed the complete assignment of all amide resonances of the -(Glu)5-sequence in water and in 90% TFE. 4oo. Peak positions were measured relative to tetramethylsilane as internal standard.

Melting points were determined by Leitz Labolux 12 and are uncorrected. Optical rotations were measured in a thermostated 1-dm cell on a Perkin-Elmer CCC 0006-3525/90/7-80847-08 $04.00 241 polarimeter. Microanalyses were conducted on