Delta receptors analogues

OTHER HIGHLY POTENT SELECTIVE DELTA OPIOID RECEPTOR ANALOGUES... 

The N-terminal tetrapeptides of D-Met-deltorphin and D-Ala-deltor-phins did not show preference for delta receptors over mu receptors. The common determinants concurring to the remarkably efficient targeting of deltorphins towards the delta receptors were identified through structure-activity relationship studies conducted on an extensive series of synthetic analogues. The following structural requirements explain why the deltorphins are such potent and selective delta agonists a phenolic side chain (Tyr) and a... 

Biphalin, in standard receptor-binding assays, shows twice the affinity to mu than delta receptors (Table 1). Structure-activity relationships of a series of symmetric biphalin analogues show that replacing phenylalanine residues with -chlorophenylalanine increases the affinity for delta receptors and decreases it for mu receptors, resulting in more potent and more... 

Structural analogues, which showed a distinctly higher selectivity for kappa in comparison to mu or delta receptors, have seen the light of the day. The two new racemic compoimds investigated largely are U50488 and PD 117302, whose characteristic features along with the earlier ones are enumerated in Table 10.1. 

Page D, McClory A, Mischki T, Schmidt R, Butterworth J, St-Onge S, Labarre M, Payza K, Brown W. Novel Dmt-Tic dipeptide analogues as selective delta-opioid receptor antagonists. Bioorg Med Chem Lett 2000 10 167-170. 

The geometric isomers 464 and 467 of 5(47/)-oxazolones prepared from acetophenones can be separated. Alternatively, the mixture can be isomerized under the appropriate reaction conditions to obtain the pure of (Z) or ) isomer. Each isomer can be converted to a pair of enantiomers 466 and 469 (only one enantiomer shown) (Scheme 7.152). The p-methyl phenylalanine analogues thus obtained are constrained phenylalanines and the effect of incorporation of a p-MePhe or p-MeTyr residue on the biological properties of H-Tyr-Tic-Phe-Phe-NH2 (TIPP, where Tic = l,2,3,4-tetrahydroisoquinoline-3-carboxylic acid) a delta opioid receptor antagonist, has been studied. ... 

It is N-allyl analogue of oxymorphone, have a high affinity for mu receptor and lower affinity at delta and kappa sites. It selectively antagonizes the respiratory depression produced by opioids. After intravenous administration, it antagonizes all actions of morphine. It also blocks the actions of endogenous opioid peptides. 

Endogenous Peptides for Delta Opioid Receptors and Analogues... 

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