Structure-activity studies on the nociceptin/orphanin FQ receptor antagonist 1-benzyl-N-{3-[spiroisobenzofuran-1(3H),4'-piperidin-1-yl]propyl} pyrrolidine-2-carboxamide.

Twelve derivatives of the nociceptin/orphanin FQ (N/OFQ) receptor (NOP) antagonist 1-benzyl-N-{3-[spiroisobenzofuran-1(3H),4'-piperidin-1-yl]propyl} pyrrolidine-2-carboxamide (Comp 24) were synthesized and tested in binding experiments performed on CHO(hNOP) cell membranes. Among them, a novel interesting NOP receptor antagonist (compound 35) was identified by blending chemical moieties taken from different NOP receptor ligands. In vitro in various assays, Compound 35 consistently behaved as a pure, highly potent (pA(2) in the range 8.

(S)-alpha-methyl,alpha-amino acids: a new stereocontrolled synthesis.

A new and convenient stereocontrolled synthesis of the optically pure (S)-alpha-methyl,alpha-amino acids 6(a-d) that exploits the chiral synthon 1,4-N,N-[(S)-1-phenylethyl]-piperazine-2,5-dione (1) is described. The (S)-1-phenylethyl group, bonded to each of the N-atoms of the 2,5-diketopiperazine, acts as a chiral inductor in the first alkylation, while the steric hindrance appears to be the determining factor of stereocontrol in third and forth alkylation.

Triazine compounds as antagonists at Bv8-prokineticin receptors.

On the basis of a Janssen's patent, we approached a new synthesis of some 1,3,5-triazin-4,6-diones as potential non peptidic prokineticin receptor antagonists, containing the following substitutions: (N(1) and N(5) link a 4-methoxybenzyl and a 4-ethylbenzyl, respectively; C(2) can link an amino-ethyl-guanidine (reference compound 1) or an ethylendiamine (2) or an amino-ethyl-amino-2-imidazoline (3). New compounds were assessed for PKR1 and PKR2 affinity. Antagonist properties were evaluated as inhibition of 1 nM Bv8-induced intracellular Ca2+ mobilization.

C-terminal constrained phenylalanine as a pharmacophoric unit in peptide-based proteasome inhibitors.

Here we report the synthesis and biological properties of peptide-based molecules bearing constrained analogues of phenylalanine at the C-terminal. Compounds were tested as proteasome subunits' inhibitors. Dehydro-peptides showed good inhibition, in particular against trypsin-like (T-L) proteasome activity while some C-terminal Tic-derivatives inhibit only caspase-like activity in enzymatic beta1 subunits with a certain degree of efficacy.

Further studies on the effect of lysine at the C-terminus of the Dmt-Tic opioid pharmacophore.

A wide range of activities are induced by Lys when introduced at C-terminus of the delta-opioid Dmt-Tic pharmacophore through the alpha-amine group, including: improved delta-antagonism, mu-agonism and mu-antagonism. Here we report the synthesis of a new series of compounds with the general formula H-Dmt-Tic-NH-(CH(2))(4)-CH(R)-R' (R=-NH(2), -NH-Ac, -NH-Z; R'=CO-NH-Ph, -CO-NH-CH(2)-Ph, -Bid) in which Lys is linked to Dmt-Tic through its side-chain amine group. All new compounds (1-9) displayed potent and selective delta-antagonism (MVD, pA(2)=7.