Melanotan and Melanotan-II are both analogs of the peptide hormone alpha melanocyte stimulating hormone (?-MSH) that tend to induce skin tanning. Unlike Melanotan, Melanotan-II has the additional effect of increasing libido. Melanotan II has aphrodisiac properties.
The molecular formula is C50H69N15O9. It has the amino acid sequence of Ac-Nle-cyclo [Asp-His-D-Phe-Arg-Trp-Lys]-NH2 and a molecular weight of 1024.2 Dalton. The CAS Number is 121062-08-6.