Antibody-drug conjugates (ADCs) consist of a desirable monoclonal antibody, an active cytotoxic drug and an appropriate linker. An appropriate linker between the antibody and the cytotoxic drug provides a specific bridge, and thus helps the antibody to selectively deliver the cytotoxic drug to tumor cells and accurately releases the cytotoxic drug at tumor sites. In addition to conjugation, the linkers maintain ADCs’ stability during the preparation and storage stages of the ADCs and during the systemic circulation period. The ADCs currently undergoing clinical evaluation contain linkers are mostly classified into two categories: cleavable and noncleavable. Cleavable linkers rely on processes inside the cell to liberate the toxin, such as reduction in the cytoplasm, exposure to acidic conditions in the lysosome, or cleavage by specific proteases within the cell. Noncleavable linkers require proteolytic degradation of the antibody portion of the ADC for release of the cytotoxic molecule, which will retain the linker and the amino acid by which it was attached to the antibody. The selection of linker is target dependent, based on the knowledge of the internalization and degradation of the antibody-target antigen complex, and a preclinical in vitro and in vivo activity comparison of conjugates. Moreover, the choice of a linker is also influenced by which cytotoxin is used, as each molecule has different chemical constraints, and frequently the drug structure lends itself to a specific linker.


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m-PEG9-Amine

m-PEG9-Amine is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 211859-73-3
  • MF: C19H41NO9
  • MW: 427.53000
  • Catalog: ADC Linker
  • Density: 1.06
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

SC209 intermediate-1

SC209 intermediate-1 (Compound A7a) is an ADC linker. SC209 intermediate-1 can be used for synthesis of ADCs[1].

  • CAS Number: 1977557-93-9
  • MF: C21H30N2O6
  • MW: 406.47
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Tetrazine-SS-Biotin

Tetrazine-SS-Biotin is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2123482-78-8
  • MF: C24H32N8O3S3
  • MW: 576.76
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N3-D-Orn(Boc)-OH

N3-D-Orn(Boc)-OH is a Boc-protected pentanoic amino acid derivative, can be used as a click chemistry reagent and has been used to synthesis antibody-drug conjugates (ADC)[1].

  • CAS Number: 2165877-62-1
  • MF: C10H18N4O4
  • MW: 258.27
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Acid-C3-SSPy

Acid-C3-SSPy is a cleavable DBA-DM4 linker used in the synthesis of DBA-DM4 (HY-128960), a drug-linker conjugate for ADC[1].

  • CAS Number: 250266-79-6
  • MF: C9H11NO2S2
  • MW: 229.319
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 411.6±41.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 202.7±27.6 °C

L-Ornithinamide, N-[[2-[2-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)ethoxy]ethoxy]carbonyl]-L-valyl-N5-(aminocarbonyl)-N-[4-[[[(4-nitrophenoxy)carbonyl]oxy]methyl]phenyl]-

Mal-PEG2-Val-Cit-PABA-PNP is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1345681-52-8
  • MF: C34H41N7O13
  • MW: 755.73
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

1-BOC-AZETIDINE-3-CARBOXYLICACIDMETHYLESTER

Methyl 1-Boc-azetidine-3-carboxylate is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Methyl 1-Boc-azetidine-3-carboxylate is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PROTACs[1

  • CAS Number: 610791-05-4
  • MF: C10H17NO4
  • MW: 215.246
  • Catalog: ADC Linker
  • Density: 1.2±0.1 g/cm3
  • Boiling Point: 269.0±33.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 116.5±25.4 °C

tans-4-Hydroxy-D-proline hydrochloride

tans-4-Hydroxy-D-proline hydrochloride is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). tans-4-Hydroxy-D-proline hydrochloride is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PR

  • CAS Number: 142347-81-7
  • MF: C5H10ClNO3
  • MW: 167.591
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: 368.6ºC at 760mmHg
  • Melting Point: N/A
  • Flash Point: 176.7ºC

Biotin-C4-amide-C5-NH2

Biotin-C4-amide-C5-NH2 is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 151294-96-1
  • MF: C14H26N4O2S
  • MW: 314.447
  • Catalog: ADC Linker
  • Density: 1.1±0.0 g/cm3
  • Boiling Point: 650.1±0.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 347.0±0.0 °C

Fmoc-Lys-OH hydrochloride

Fmoc-Lys-OH hydrochloride is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Fmoc-Lys-OH hydrochloride is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PROTACs[1][2].

  • CAS Number: 139262-23-0
  • MF: C21H25ClN2O4
  • MW: 404.887
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: 607.6ºC at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 321.3ºC

OH-Glu-Val-Cit-PAB-MMAE

OH-Glu-Val-Cit-PAB-MMAE consists a cleavable ADC linker (OH-Glu-Val-Cit-PAB) and a potent tubulin inhibitor (MMAE). SuO-Glu-Val-Cit-PAB-MMAE can be used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1895916-23-0
  • MF: C63H100N10O15
  • MW: 1237.53
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG6-acid

Propargyl-PEG6-acid is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1951438-84-8
  • MF: C16H28O8
  • MW: 348.389
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 462.8±45.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 157.6±22.2 °C

diSPhMC-Asn-Pro-Val-PABC-MMAE

diSPhMC-Asn-Pro-Val-PABC-MMAE (compound 9) is a potent ADC Linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2893871-68-4
  • MF: C83H115N11O16S2
  • MW: 1587.00
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-PEG4-Ala-Ala-Asn-PAB

Fmoc-PEG4-Ala-Ala-Asn-PAB is a cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2055048-57-0
  • MF: C43H55N5O13
  • MW: 849.92
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

S-(1-Hydroxy-2-methylpropan-2-yl) methanesulfonothioate

S-(1-Hydroxy-2-methylpropan-2-yl) methanesulfonothioate is a glutathione cleavable ADC linker used for the antibody-drug conjugates (ADCs) and refers to the Alkyl-Chain composition. S-(1-Hydroxy-2-methylpropan-2-yl) methanesulfonothioate is the linker portions of the molecules employed for mAb attachment purposes[1].

  • CAS Number: 2127875-65-2
  • MF: C5H12O3S2
  • MW: 184.28
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Boc-Gly-PEG3-endo-BCN

Boc-gly-PEG3-endo-BCN is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. Boc-gly-PEG3-endo-BCN is also a cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 2110444-63-6
  • MF: C28H47N3O8
  • MW: 553.69
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

m-PEG10-amine

m-PEG10-amine is a non-cleavable 10 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1]. m-PEG10-amine is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1].

  • CAS Number: 1383658-09-0
  • MF: C21H45NO10
  • MW: 471.583
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 518.9±45.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 254.4±22.4 °C

HO-PEG10-CH2CH2COO<sup>t</sup>Bu

Hydroxy-PEG10-Boc is extacted from patent CN108707228 (example 0024)[1]. Hydroxy-PEG10-Boc is a uncleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Hydroxy-PEG10-Boc can be conjugated to Paclitaxel (HY-B0015) or docetaxel (HY-B0011)[2].

  • CAS Number: 778596-26-2
  • MF: C27H54O13
  • MW: 586.71000
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Ald-Ph-amido-PEG3-NHS ester

Ald-Ph-amido-PEG3-NHS ester is a non-cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2101206-32-8
  • MF: C21H26N2O9
  • MW: 450.44
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Tr-PEG3-OH

Tr-PEG3-OH is a non-cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 133699-09-9
  • MF: C25H28O4
  • MW: 392.48700
  • Catalog: ADC Linker
  • Density: 1.126±0.06 g/cm3(Predicted)
  • Boiling Point: 521.8±45.0 °C(Predicted)
  • Melting Point: N/A
  • Flash Point: N/A

Mal-PEG4-VC-PAB-DMEA

Mal-PEG4-VC-PAB-DMEA is a cleavable ADC linker containing a Maleimide group. Mal-PEG4-VC-PAB-DMEA is used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1569261-93-3
  • MF: C41H65N9O13
  • MW: 892.01
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Me-triacetyl-β-D-glucopyranuronate-Ph-ald-NO2

Me-triacetyl-β-D-glucopyranuronate-Ph-ald-NO2 is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 148579-93-5
  • MF: C20H21NO13
  • MW: 483.380
  • Catalog: ADC Linker
  • Density: 1.4±0.1 g/cm3
  • Boiling Point: 582.6±50.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 219.6±32.1 °C

Amino-PEG4-CH2COOH

Amino-PEG4-CH2COOH is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. Amino-PEG4-CH2COOH is also a non-cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 195071-49-9
  • MF: C10H21NO6
  • MW: 251.27700
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Asn-Pro-Val-PABC-MMAE TFA

Asn-Pro-Val-PABC-MMAE TFA (compound 8) is a potent ADC Linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2893871-67-3
  • MF: C63H97F3N10O15
  • MW: 1291.50
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Boc-Val-Ala-PAB

Boc-Val-Ala-PAB is a cathepsin cleavable ADC linker that is used for making antibody-drug conjugate (ADCs)[1][2].

  • CAS Number: 1884577-99-4
  • MF: C20H31N3O5
  • MW: 393.48
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG3-acid

Propargyl-PEG3-acid is a non-cleavable (3 unit PEG) ADC linker and also a PEG-based PROTAC linker that can be used to synthesis 6-OHDA-PEG3-yne. 6-OHDA-PEG3-yne contains 6-OHDA (HY-B1081, HY-B1081A) and Propargyl-PEG3-acid[1].

  • CAS Number: 1347760-82-0
  • MF: C10H16O5
  • MW: 216.231
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 348.0±32.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 131.8±18.6 °C

BCN-PEG4-HyNic

BCN-PEG4-HyNic is a cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1507370-54-8
  • MF: C28H41N5O6
  • MW: 543.66
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-Gly-Gly-allyl propionate

Fmoc-Gly-Gly-allyl propionate is a cleavable linker that can be used to synthesize Antibody-Drug Conjugates (ADCs).

  • CAS Number: 2766214-15-5
  • MF: C25H26N2O7
  • MW: 466.48
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-Val-Ala-aminomethyl acetate

Fmoc-Val-Ala-aminomethyl acetate (Compound 58b) is an ADC Linker, and can be used for synthesis of ADCs[1].

  • CAS Number: 2505045-86-1
  • MF: C26H31N3O6
  • MW: 481.54
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Maleic anhydride-1,4-13C2

Succinic anhydride-13C2 is the 13C labeled Succinic anhydride[1]. Succinic anhydride is a cyclic anhydride and a nonclaevable ADC linker extracted from patent WO2009064913A1. Succinic anhydride can react with compound 4 of the patent to link the prodrug to an amine or hydroxy 1 group of a targeting polypeptide[2].

  • CAS Number: 67519-25-9
  • MF: C4H4O3
  • MW: 102.05800
  • Catalog: ADC Linker
  • Density: 1.4±0.1 g/cm3
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A