Peptide Reference Data: Molecular Formula, Mass, CAS Number and Sequence

Name: Peptide Reference Data: molecular formula, mass, CAS number and sequence
Creator: The Peptide Review

Theoretical masses, formulas, CAS numbers and verified sequences for 30 research compounds, each linked to its PubChem record.

Research use only. Reference information for laboratory research materials. Not medical or usage guidance.

A certificate of analysis confirms identity by mass spectrometry: the lab reports an observed mass, and that number only means something next to the theoretical mass of the compound named on the label. This page collects those theoretical values in one place, with the source record for each, so a reported mass can be checked in seconds.

Everything here is chemistry reference data for laboratory research materials. Nothing on this page concerns human or animal use.

How to use this table with a certificate of analysis

Find the mass spectrometry section of the certificate and note the observed mass.
Compare it with the row below. Most labs report either the average mass or the monoisotopic mass, and electrospray instruments often show charged forms such as [M+H]+ (mass plus about 1.007) or [M+2H]2+ (mass plus about 2.015, divided by two).
If the observed value matches neither mass nor a simple charged form of it, the material may be a different variant, a salt form, or a different compound. Our guide on how to read a peptide certificate of analysis covers what to check next, and how to verify a COA is genuine covers confirming the report with the lab.

Reference table

Values retrieved from PubChem on 29 September 2026. Sequences use one-letter amino acid codes unless written out.
Compound	Sequence	Molecular formula	Average mass (g/mol)	Monoisotopic mass (Da)	CAS number	PubChem CID
BPC-157	GEPPPGKPADDAGLV	C₆₂H₉₈N₁₆O₂₂	1419.5	1418.7042	137525-51-0	9941957
TB-500 (fragment)	Ac-LKKTETQ	C₃₈H₆₈N₁₀O₁₄	889.0	888.4916	885340-08-9	62707662
Thymosin β4 (full length)	Ac-SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES	C₂₁₂H₃₅₀N₅₆O₇₈S	4963	4960.4863	—	45382195
GHK-Cu	Gly-His-Lys (copper complex)	C₁₄H₂₃CuN₆O₄⁺	402.92	402.1077	89030-95-5	71587328
Semax	MEHFPGP	C₃₇H₅₁N₉O₁₀S	813.9	813.3480	80714-61-0	9811102
Selank	TKPRPGP	C₃₃H₅₇N₁₁O₉	751.9	751.4341	129954-34-3	11765600
MOTS-c	MRWQEMGYIFYPRKLR	C₁₀₁H₁₅₂N₂₈O₂₂S₂	2174.6	2173.1077	1627580-64-6	146675088
KPV	KPV	C₁₆H₃₀N₄O₄	342.43	342.2267	67727-97-3	125672
Epitalon	AEDG	C₁₄H₂₂N₄O₉	390.35	390.1387	307297-39-8	219042
SS-31	D-Arg-Dmt-Lys-Phe-NH2	C₃₂H₄₉N₉O₅	639.8	639.3857	736992-21-5	11764719
Ipamorelin	Aib-His-D-2-Nal-D-Phe-Lys-NH2	C₃₈H₄₉N₉O₅	711.9	711.3857	170851-70-4	9831659
CJC-1295 (with DAC)	—	C₁₆₅H₂₆₉N₄₇O₄₆	3647.2	3645.0155	446262-90-4	91971820
Sermorelin	YADAIFTNSYRKVLGQLSARKLLQDIMSR-NH2	C₁₄₉H₂₄₆N₄₄O₄₂S	3357.9	3355.8187	86168-78-7	16132413
Tesamorelin	—	C₂₂₁H₃₆₆N₇₂O₆₇S	5136	5132.7166	218949-48-5	16137828
GHRP-2	D-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2	C₄₅H₅₅N₉O₆	818.0	817.4275	158861-67-7	6918245
GHRP-6	His-D-Trp-Ala-Trp-D-Phe-Lys-NH2	C₄₆H₅₆N₁₂O₆	873.0	872.4446	—	4345065
Hexarelin	—	C₄₇H₅₈N₁₂O₆	887.0	886.4602	140703-51-1	6918297
AOD-9604	YLRIVQCRSVEGSCGF (Cys7-Cys14 disulfide)	C₇₈H₁₂₃N₂₃O₂₃S₂	1815.1	1813.8604	221231-10-3	71300630
Thymosin α1	Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN	C₁₂₉H₂₁₅N₃₃O₅₅	3108.3	3106.5041	62304-98-7	16130571
DSIP	WAGGDASGE	C₃₅H₄₈N₁₀O₁₅	848.8	848.3301	62568-57-4	68816
Kisspeptin-10	YNWNSFGLRF-NH2	C₆₃H₈₃N₁₇O₁₄	1302.4	1301.6305	374675-21-5	25240297
LL-37	LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES	C₂₀₅H₃₄₀N₆₀O₅₃	4493	4490.5754	154947-66-7	16198951
Oxytocin	CYIQNCPLG-NH2 (Cys1-Cys6 disulfide)	C₄₃H₆₆N₁₂O₁₂S₂	1007.2	1006.4365	50-56-6	439302
Bremelanotide	—	C₅₀H₆₈N₁₄O₁₀	1025.2	1024.5243	189691-06-3	9941379
Melanotan II	—	C₅₀H₆₉N₁₅O₉	1024.2	1023.5403	121062-08-6	92432
Semaglutide	—	C₁₈₇H₂₉₁N₄₅O₅₉	4114	4111.1154	910463-68-2	56843331
Tirzepatide	—	C₂₂₅H₃₄₈N₄₈O₆₈	4813	4810.5249	2023788-19-2	166567236
Cagrilintide	—	C₁₉₄H₃₁₂N₅₄O₅₉S₂	4409	4406.2515	1415456-99-3	171397054
NAD+	Not a peptide	C₂₁H₂₇N₇O₁₄P₂	663.4	663.1091	53-84-9	5892
5-Amino-1MQ	Not a peptide	C₁₀H₁₁N₂⁺	159.21	159.0922	685079-15-6	950107

Copy this table as CSV

compound,also_known_as,sequence,molecular_formula,average_mass_g_per_mol,monoisotopic_mass_da,cas_number,pubchem_cid,pubchem_url,note
BPC-157,Body protection compound 157; pentadecapeptide,GEPPPGKPADDAGLV,C62H98N16O22,1419.5,1418.7042,137525-51-0,9941957,https://pubchem.ncbi.nlm.nih.gov/compound/9941957,
TB-500 (fragment),"Thymosin β4 fragment 17-23, N-acetylated",Ac-LKKTETQ,C38H68N10O14,889.0,888.4916,885340-08-9,62707662,https://pubchem.ncbi.nlm.nih.gov/compound/62707662,The name TB-500 is also used loosely for full-length thymosin β4. The certificate of analysis mass shows which one was tested.
Thymosin β4 (full length),Tβ4; timbetasin,Ac-SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES,C212H350N56O78S,4963,4960.4863,,45382195,https://pubchem.ncbi.nlm.nih.gov/compound/45382195,
GHK-Cu,Prezatide copper; copper tripeptide-1,Gly-His-Lys (copper complex),C14H23CuN6O4+,402.92,402.1077,89030-95-5,71587328,https://pubchem.ncbi.nlm.nih.gov/compound/71587328,Formula and mass are for the 1:1 copper complex as recorded in PubChem. Salt and hydrate forms differ.
Semax,ACTH(4-7)-Pro-Gly-Pro,MEHFPGP,C37H51N9O10S,813.9,813.3480,80714-61-0,9811102,https://pubchem.ncbi.nlm.nih.gov/compound/9811102,N-acetyl and amidated variants have different masses.
Selank,"Tuftsin analog, Thr-Lys-Pro-Arg-Pro-Gly-Pro",TKPRPGP,C33H57N11O9,751.9,751.4341,129954-34-3,11765600,https://pubchem.ncbi.nlm.nih.gov/compound/11765600,N-acetyl and amidated variants have different masses.
MOTS-c,Mitochondrial ORF of the 12S rRNA type-c,MRWQEMGYIFYPRKLR,C101H152N28O22S2,2174.6,2173.1077,1627580-64-6,146675088,https://pubchem.ncbi.nlm.nih.gov/compound/146675088,
KPV,α-MSH (11-13),KPV,C16H30N4O4,342.43,342.2267,67727-97-3,125672,https://pubchem.ncbi.nlm.nih.gov/compound/125672,
Epitalon,Epithalon; Ala-Glu-Asp-Gly,AEDG,C14H22N4O9,390.35,390.1387,307297-39-8,219042,https://pubchem.ncbi.nlm.nih.gov/compound/219042,
SS-31,"Elamipretide; MTP-131; Dmt = 2,6-dimethyltyrosine",D-Arg-Dmt-Lys-Phe-NH2,C32H49N9O5,639.8,639.3857,736992-21-5,11764719,https://pubchem.ncbi.nlm.nih.gov/compound/11764719,
Ipamorelin,"NNC 26-0161; Aib = 2-aminoisobutyric acid, Nal = naphthylalanine",Aib-His-D-2-Nal-D-Phe-Lys-NH2,C38H49N9O5,711.9,711.3857,170851-70-4,9831659,https://pubchem.ncbi.nlm.nih.gov/compound/9831659,
CJC-1295 (with DAC),DAC:GRF,,C165H269N47O46,3647.2,3645.0155,446262-90-4,91971820,https://pubchem.ncbi.nlm.nih.gov/compound/91971820,"This PubChem record is the DAC form. The form sold as ""CJC-1295 without DAC"" (modified GRF 1-29) is a different, lighter molecule with no PubChem record under that name."
Sermorelin,GHRH (1-29) amide,YADAIFTNSYRKVLGQLSARKLLQDIMSR-NH2,C149H246N44O42S,3357.9,3355.8187,86168-78-7,16132413,https://pubchem.ncbi.nlm.nih.gov/compound/16132413,
Tesamorelin,trans-3-hexenoyl GHRH (1-44) amide,,C221H366N72O67S,5136,5132.7166,218949-48-5,16137828,https://pubchem.ncbi.nlm.nih.gov/compound/16137828,
GHRP-2,Pralmorelin,D-Ala-D-2-Nal-Ala-Trp-D-Phe-Lys-NH2,C45H55N9O6,818.0,817.4275,158861-67-7,6918245,https://pubchem.ncbi.nlm.nih.gov/compound/6918245,
GHRP-6,Growth hormone releasing hexapeptide,His-D-Trp-Ala-Trp-D-Phe-Lys-NH2,C46H56N12O6,873.0,872.4446,,4345065,https://pubchem.ncbi.nlm.nih.gov/compound/4345065,
Hexarelin,Examorelin,,C47H58N12O6,887.0,886.4602,140703-51-1,6918297,https://pubchem.ncbi.nlm.nih.gov/compound/6918297,
AOD-9604,hGH fragment 177-191 analog,YLRIVQCRSVEGSCGF (Cys7-Cys14 disulfide),C78H123N23O23S2,1815.1,1813.8604,221231-10-3,71300630,https://pubchem.ncbi.nlm.nih.gov/compound/71300630,
Thymosin α1,Thymalfasin,Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN,C129H215N33O55,3108.3,3106.5041,62304-98-7,16130571,https://pubchem.ncbi.nlm.nih.gov/compound/16130571,
DSIP,Delta sleep-inducing peptide,WAGGDASGE,C35H48N10O15,848.8,848.3301,62568-57-4,68816,https://pubchem.ncbi.nlm.nih.gov/compound/68816,
Kisspeptin-10,Metastin (45-54),YNWNSFGLRF-NH2,C63H83N17O14,1302.4,1301.6305,374675-21-5,25240297,https://pubchem.ncbi.nlm.nih.gov/compound/25240297,
LL-37,Human cathelicidin fragment,LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES,C205H340N60O53,4493,4490.5754,154947-66-7,16198951,https://pubchem.ncbi.nlm.nih.gov/compound/16198951,
Oxytocin,,CYIQNCPLG-NH2 (Cys1-Cys6 disulfide),C43H66N12O12S2,1007.2,1006.4365,50-56-6,439302,https://pubchem.ncbi.nlm.nih.gov/compound/439302,
Bremelanotide,PT-141,,C50H68N14O10,1025.2,1024.5243,189691-06-3,9941379,https://pubchem.ncbi.nlm.nih.gov/compound/9941379,
Melanotan II,MT-II,,C50H69N15O9,1024.2,1023.5403,121062-08-6,92432,https://pubchem.ncbi.nlm.nih.gov/compound/92432,
Semaglutide,,,C187H291N45O59,4114,4111.1154,910463-68-2,56843331,https://pubchem.ncbi.nlm.nih.gov/compound/56843331,
Tirzepatide,LY3298176,,C225H348N48O68,4813,4810.5249,2023788-19-2,166567236,https://pubchem.ncbi.nlm.nih.gov/compound/166567236,
Cagrilintide,,,C194H312N54O59S2,4409,4406.2515,1415456-99-3,171397054,https://pubchem.ncbi.nlm.nih.gov/compound/171397054,
NAD+,Nicotinamide adenine dinucleotide; nadide,Not a peptide,C21H27N7O14P2,663.4,663.1091,53-84-9,5892,https://pubchem.ncbi.nlm.nih.gov/compound/5892,
5-Amino-1MQ,5-amino-1-methylquinolinium,Not a peptide,C10H11N2+,159.21,159.0922,685079-15-6,950107,https://pubchem.ncbi.nlm.nih.gov/compound/950107,Formula and mass are for the cation. Supplied salts such as the iodide are heavier.

Notes on specific compounds

TB-500 (fragment). The name TB-500 is also used loosely for full-length thymosin β4. The certificate of analysis mass shows which one was tested.
GHK-Cu. Formula and mass are for the 1:1 copper complex as recorded in PubChem. Salt and hydrate forms differ.
Semax. N-acetyl and amidated variants have different masses.
Selank. N-acetyl and amidated variants have different masses.
CJC-1295 (with DAC). This PubChem record is the DAC form. The form sold as "CJC-1295 without DAC" (modified GRF 1-29) is a different, lighter molecule with no PubChem record under that name.
5-Amino-1MQ. Formula and mass are for the cation. Supplied salts such as the iodide are heavier.

Other names used for these compounds

BPC-157: Body protection compound 157; pentadecapeptide
TB-500 (fragment): Thymosin β4 fragment 17-23, N-acetylated
Thymosin β4 (full length): Tβ4; timbetasin
GHK-Cu: Prezatide copper; copper tripeptide-1
Semax: ACTH(4-7)-Pro-Gly-Pro
Selank: Tuftsin analog, Thr-Lys-Pro-Arg-Pro-Gly-Pro
MOTS-c: Mitochondrial ORF of the 12S rRNA type-c
KPV: α-MSH (11-13)
Epitalon: Epithalon; Ala-Glu-Asp-Gly
SS-31: Elamipretide; MTP-131; Dmt = 2,6-dimethyltyrosine
Ipamorelin: NNC 26-0161; Aib = 2-aminoisobutyric acid, Nal = naphthylalanine
CJC-1295 (with DAC): DAC:GRF
Sermorelin: GHRH (1-29) amide
Tesamorelin: trans-3-hexenoyl GHRH (1-44) amide
GHRP-2: Pralmorelin
GHRP-6: Growth hormone releasing hexapeptide
Hexarelin: Examorelin
AOD-9604: hGH fragment 177-191 analog
Thymosin α1: Thymalfasin
DSIP: Delta sleep-inducing peptide
Kisspeptin-10: Metastin (45-54)
LL-37: Human cathelicidin fragment
Bremelanotide: PT-141
Melanotan II: MT-II
Tirzepatide: LY3298176
NAD+: Nicotinamide adenine dinucleotide; nadide
5-Amino-1MQ: 5-amino-1-methylquinolinium

Method and sources

Molecular formula, average mass, monoisotopic mass and CAS registry number were retrieved from the PubChem compound record linked in each row on 29 September 2026. Where a record lists more than one CAS number, the one PubChem cites most often is shown. A dash means the PubChem record lists none.

Sequences were checked by composition: the elemental formula was computed from the listed residues, including N-terminal acetylation, C-terminal amidation and disulfide bonds where present, and had to equal the PubChem formula exactly. A sequence is shown only where that check passed. Composition confirms the residues and modifications, not their order, so the order follows the published literature for each compound.

Average mass uses standard atomic weights and is what a balance and most purity calculations assume. Monoisotopic mass uses the most abundant isotope of each element and is what a high-resolution mass spectrometer resolves.

Citing and reusing this data

This table is free to reuse with attribution. Suggested citation: The Peptide Review, "Peptide Reference Data," thepeptidereview.co/peptide-reference-data/, retrieved on the date you accessed it. Corrections are welcome through the contact details on our editorial policy page.