Science · Signaling & Neuroactive
Research class
Signaling & Neuroactive
Compounds studied in relation to neuropeptide and melanocortin signaling. This is the most structurally coherent class on the site: it contains the cyclic lactam-bridged melanocortin analogs alongside short linear neuropeptides, and the contrast between the two is a useful lesson in how conformational constraint is engineered.
18
Compounds
275 – 3327
Molecular weight (g/mol)
7 / 18
Verified identifiers
Compounds in this class
Each has a full monograph: verified identifiers, sequence, and analytical properties.
Semax
C37H51N9O10S · 813.93
Selank
C33H57N11O9 · 751.89
Epithalon
C14H22N4O9 · 390.35
DSIP
C35H48N10O15 · 848.82
PT-141
C50H68N14O10 · 1025.18
MT-1 (Melanotan 1)
C78H111N21O19 · 1646.87
MT-2 (Melanotan 2)
C50H69N15O9 · 1024.20
Tesofensine
C17H23Cl2NO · 328.28
Dihexa
C27H44N4O5 · 504.66
Pinealon
C15H26N6O8 · 418.41
VIP (Vasoactive Intestinal Peptide)
C147H237N43O43S · 3326.83
P21
C27H42N6O8 · 578.67
SNAP-8
C41H70N16O16S · 1075.17
Humanin
C119H204N34O32S2 · 2687.27
Vilon
C11H21N3O5 · 275.30
Testagen
C17H29N5O9 · 447.44
Vesugen
C15H26N4O8 · 390.39
Cortagen
C17H26N4O9 · 430.41
Shared chemistry
The melanocortin analogs share a cyclic lactam bridge and non-standard residues — the clearest example on the site of deliberate structural constraint.
Cyclic lactamPT-141, MT-2 — Asp2–Lys7 bridge
Non-standard residuesNorleucine (Nle), D-phenylalanine
Terminal chemistryN-acetyl; C-terminal amide vs free acid
People also ask
What are signaling and neuroactive peptides?
They are a research grouping of peptides studied in relation to neuropeptide and melanocortin signaling. The name describes the research context, not an established effect or use. All members are supplied for laboratory research only.
What is a cyclic lactam bridge?
A cyclic lactam bridge is a covalent amide bond formed between two amino-acid side chains — for example the Asp2–Lys7 bridge in the melanocortin analogs. It locks part of the peptide into a fixed ring, constraining its conformation, and is a clear example of deliberate structural engineering.
Which compounds in this class are melanocortin analogs?
The cyclic melanocortin analogs in this grouping include PT-141 and MT-2 (Melanotan 2), both cyclic seven-residue structures, alongside MT-1 (Melanotan 1). They are described here by structure only — the cyclic constraint and their non-standard residues.
What are non-standard amino-acid residues?
Non-standard residues are amino acids outside the twenty canonical ones, incorporated to modify a peptide's structure. In this grouping the melanocortin analogs use residues such as norleucine (Nle) and D-phenylalanine, which is why they cannot be described by a plain natural-sequence string alone.
How do the linear and cyclic peptides in this class differ?
The short linear neuropeptides (such as Semax, Selank, and DSIP) are open chains, while the melanocortin analogs are cyclized through a lactam bridge. The difference is one of conformational constraint: the cyclic members are held in a fixed ring, the linear members are not.
Are these peptides approved for human or veterinary use?
No. Every compound grouped here is supplied For Research Use Only — not for human or veterinary use. The materials are not drugs, foods, cosmetics, or medical devices and must not be administered to humans or animals.
Data & tools
Peptide fundamentals
Analytical data & tools
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Every compound in this class has a full monograph and a per-lot certificate. Pricing and ordering open for verified research professionals.