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Updated: Jun 22, 2026

Multi-Faceted Mass Spectrometric Investigation of Neuropeptides in Callinectes sapidus
Published on: May 31, 2022
Synthesis and evaluation of new endomorphin analogues modified at the Pro(2) residue
Domenica Torino1, Adriano Mollica, Francesco Pinnen
1Dipartimento di Chimica e Tecnologie del Farmaco e Istituto di Chimica Biomolecolare, CNR Sezione di Roma, Sapienza, Università di Roma, P.le A. Moro 5, 00185 Roma, Italy.
Abstract:
Six new endomorphin analogues, incorporating constrained amino acids in place of native proline have been synthesized. Residues of (S)-azetidine-2-carboxylic acid (Aze), 3,4-dehydro-(S)-proline (Delta(3)Pro), azetidine-3-carboxylic acid (3Aze) and dehydro-alanine (DeltaAla) have been used to prepare [Delta(3)Pro(2)]EM-2 (1), [Aze(2)]EM-1 (2), [Aze(2)]EM-2 (3), [3Aze(2)]EM-1 (4), [3Aze(2)]EM-2 (5) and [DeltaAla(2)]EM-2 (6). Binding assays and functional bioactivities for mu- and delta-receptors are reported. The highest affinity, bioactivity and selectivity are shown by peptides 2 and 3 containing the Aze residue.
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