Description
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of Ξ±-melanocyte-stimulating hormone (Ξ±-MSH), developed at the University of Arizona in the late 1980s as a research compound for melanocortin receptor pharmacology. The peptide consists of a truncated Ξ±-MSH core with three key modifications: a norleucine substitution at position 4 (replacing oxidation-prone methionine), a D-phenylalanine substitution at position 7 (enhancing receptor binding), and an AspΒ²-Lysβ· lactam bridge creating a constrained cyclic backbone. MT-II functions as a non-selective melanocortin receptor agonist with activity at all five subtypes (MC1R, MC2R, MC3R, MC4R, MC5R), making it one of the most extensively characterized broad-spectrum melanocortin agonists in research literature. Structurally, MT-II differs from PT-141 (bremelanotide) by a single functional group β the C-terminal amide of MT-II versus the carboxylic acid of PT-141 β which is studied for its dramatic effect on receptor subtype selectivity profiles. The compound is investigated extensively in preclinical research for melanocortin receptor pharmacology, melanogenic pathway activation, and structure-activity relationship (SAR) studies of cyclic melanocortin analogs.
Benefits (Research Focus)
β’ Non-selective melanocortin agonism β studied as a broad-spectrum MC1R/MC2R/MC3R/MC4R/MC5R agonist for receptor pharmacology research
β’ Melanogenic pathway research β investigated for cAMP, MITF, and tyrosinase activation in melanocyte cell models
β’ Cyclic peptide pharmacology β explored for the role of the AspΒ²-Lysβ· lactam bridge in receptor binding stability
β’ Comparative SAR research β examined as a reference compound versus PT-141, MT-1, and other melanocortin analogs
β’ Receptor subtype profiling β researched for differential agonist activity across the five melanocortin receptor subtypes
What Researchers Look At
β’ MC1R, MC2R, MC3R, MC4R, and MC5R receptor binding affinity and selectivity profiles
β’ cAMP signaling and downstream MITF transcriptional activation in melanocyte cultures
β’ Tyrosinase activity, eumelanin/pheomelanin ratios, and melanogenic gene expression panels
β’ Hypothalamic neuronal activation patterns following non-selective melanocortin agonism
β’ Comparative pharmacology versus PT-141 (cyclic, C-terminal -OH), Ξ±-MSH, and Melanotan I (linear, MC1R-selective)
Quick Specs
β’ Form: Lyophilized white powder
β’ Net Peptide Content: 10 mg per vial
β’ Quantity: 1 vial
β’ Appearance: White to off-white lyophilizate
β’ Reconstitution: Bacteriostatic or sterile water (added by the end researcher)
β’ Purity: β₯99% by HPLC
β’ Identity: MS-verified (per COA)
β’ Storage: Protect from light
Identity Basics
β’ Compound: Melanotan II (MT-II)
β’ Synonyms: MT-2; MT II; Melanotan 2; [Nleβ΄, D-Pheβ·]-Ξ±-MSH(4-10) cyclic
β’ Class: Cyclic heptapeptide; non-selective melanocortin receptor agonist; Ξ±-MSH(4-10) analog
β’ Sequence: Ac-Nle-cyclo(Asp-His-D-Phe-Arg-Trp-Lys)-NHβ
β’ Structural features: N-acetylated norleucine at position 1; lactam bridge between AspΒ² and Lysβ·; C-terminal amidation; 7 amino acids in cyclic backbone
β’ Structural relationship: Differs from PT-141 (bremelanotide) only by C-terminal functional group β MT-II has -NHβ (amide) vs PT-141 -OH (acid)
β’ Formula / M.W.: C50H69N15O9, ~1024.18 g/mol
β’ CAS: 121062-08-6
β οΈ Disclaimer
- This product is intended for laboratory research use only.
- Not for human or veterinary use.
- Not approved for diagnostic, therapeutic, or medical applications.
- Handle using appropriate laboratory safety procedures and personal protective equipment.
COA Verification Notice: Even if the vial label or product image states a certain concentration, always go by the COA for the true verified value. We reference the COA to determine the verified concentration and purity of each product, regardless of what the label or product image indicates.







