P21

P21 is a small synthetic peptidomimetic derived from a four-residue active fragment of ciliary neurotrophic factor (CNTF), in which an adamantane-modified residue — the "(A)" position in the notation Ac-DGGL(A)G-NH2 — stands in place of an ordinary amino acid, N-acetylated and C-terminally amidated. It is listed here strictly as an analytical reference entity — it is not sold, stocked, or certified by Lineará, and has no price or certificate of analysis. The data on this page is characterization only: molecular formula C27H42N6O8 and the values computed from it. No biological activity, mechanism, or use is described or implied.

P21 has the sequence Ac-DGGL(A)G-NH2. P21 is written Ac-DGGL(A)G-NH2, where the "(A)" at position 5 is not an alanine but an adamantane-based amino-acid residue — a compact, highly lipophilic cage carried on the backbone. The peptide is N-acetylated at the N-terminus and bears a primary amide at the C-terminus. Its stereodescriptor-bearing InChIKey, LUJZBZPLIRWWGJ-NBONATBJSA-N, was machine-verified against PubChem CID 56589645 at build (formula C27H42N6O8), so the molecular identity is reconciled. A computed 3D conformer is deliberately withheld: PubChem carries no 3D record for this compound and leaves two carbons of the adamantyl cage stereochemically undefined, so embedding one would force a chirality the source record does not assert. The residue-chain schematic is drawn, with the adamantane unit shown as a single non-standard token rather than a standard backbone amino acid — the deposited structure resolves it as one cage bearing both the backbone amide and the C-terminal carboxamide, which does not map cleanly onto a linear per-residue chain.

P21 has the molecular formula C27H42N6O8, giving an average molecular weight of 578.67 g/mol and a computed monoisotopic mass of 578.3064 Da.

The CAS Registry Number for P21 is 1246751-68-7. Its PubChem CID is 56589645 and its InChIKey is LUJZBZPLIRWWGJ-NBONATBJSA-N.

Yes. P21 is a peptide — a chain of amino-acid residues joined by peptide bonds, 6 residues in length. Its identity is defined by that sequence and its molecular mass.

As a research material, P21 is typically handled as a lyophilized (freeze-dried) powder. It is kept desiccated and cold — commonly 2–8 °C for short periods and −20 °C for longer storage — and reconstituted in sterile or bacteriostatic water. This is storage and handling information only, not a use protocol.

No. P21 is listed here only as an analytical reference entity. It is not part of the Lineará formulary, has no price or certificate of analysis, and is not offered for sale.

No. P21 is presented strictly as characterization reference data. It is not a drug, is not approved for any human or veterinary use, and must not be administered to humans or animals.