[D-Arg1,D-Phe5,D-Trp7,11]-Substance P is a full-length Substance P analog containing D-Arg1, D-Phe5 and D-Trp substitutions at positions 7 and 11.

The modifications alter both the N-terminal stereochemistry and the aromatic/hydrophobic character of the C-terminal receptor-interaction region, making this peptide suitable for comparative Substance P structure–activity studies.

Product Information

A Major Change at the C-Terminal Residue

Native Substance P terminates in Met-NH₂. This analog instead terminates in D-Trp-NH₂, replacing a flexible sulfur-containing aliphatic side chain with a bulky aromatic indole in the opposite stereochemical configuration.

This modification simultaneously removes the Met11 oxidation site and substantially changes C-terminal receptor-facing chemistry.

Why Direct Functional Validation Is Important

The analog contains several non-conservative changes, so native Substance P potency should not be assumed. We recommend measuring receptor binding or functional response directly under the intended assay conditions.

This is particularly important for heavily D-substituted Substance P analogs because apparent agonism or antagonism can vary with receptor population, tissue and assay format.

Research Applications

The peptide can support Substance P SAR, D-amino-acid peptide studies, C-terminal residue comparisons and investigations of how stereochemistry affects tachykinin receptor interactions.

Related D-amino-acid analogs can be produced through our Chemical Peptide Synthesis service.

Frequently Asked Questions

Why is no CAS listed?

Available registry sources show inconsistent structure assignments for this name, so a CAS number is not reported here without unambiguous compound-level verification.

Does the peptide contain methionine?

No. Native Met11 is replaced by D-Trp.

How many D-residues are present?

Four: D-Arg1, D-Phe5, D-Trp7 and D-Trp11.

Research Use Only.