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-PEG7-Ms

m-PEG7-Ms is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 477775-57-8
  • MF: C16H34O10S
  • MW: 418.50000
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

SCO-PEG7-Maleimide

SCO-PEG7-Maleimide is a cleavable ADC Linker containing 3 PEG units. SCO-PEG7-Maleimide can be used as a copper-free click chemical reagent for catalyst-free click reactions. Its maleimide group (-Maleimide) degrades in aqueous media and has been used in drug delivery studies.

  • CAS Number: 2143968-81-2
  • MF: C32H51N3O12
  • MW: 669.76
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-PEG2-NH2

MC-PEG2-NH2 is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 640267-62-5
  • MF: C16H27N3O5
  • MW: 341.40
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Glu(OtBu)-Val-Cit-PAB-OH

Glu(OtBu)-Val-Cit-PAB-OH (compound L5-1c) is an non-cleavable ADC linker. Glu(OtBu)-Val-Cit-PAB-OH has been used to synthesis protein-tubulysin conjugates[1].

  • CAS Number: 2757059-05-3
  • MF: C27H44N6O7
  • MW: 564.67
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

BDP FL DBCO

BDP FL DBCO is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2093197-94-3
  • MF: C32H29BF2N4O2
  • MW: 550.41
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azido-PEG2-C2-amine

Azido-PEG2-C2-amine (N3-PEG2-CH2CH2NH2) is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. Azido-PEG2-C2-amine is also a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 166388-57-4
  • MF: C6H14N4O2
  • MW: 174.20100
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N-Boc-N-bis(PEG4-OH)

N-Boc-N-bis(PEG4-OH) is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2093154-01-7
  • MF: C21H43NO10
  • MW: 469.57
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Hydroxy-PEG3-(CH2)2-Boc

Hydroxy-PEG2-(CH2)2-Boc is a uncleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Hydroxy-PEG2-(CH2)2-Boc is extracted from patent WO2004008101A2 (compound 196)[1].

  • CAS Number: 186020-66-6
  • MF: C13H26O6
  • MW: 278.34200
  • Catalog: ADC Linker
  • Density: 1.057g/cm3
  • Boiling Point: 365.8ºC at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 125.2ºC

DBCO-acid

DBCO-acid is a cleavable ADC linker used in the synthesis of ADC linker DBCO-NHS ester (HY-115524 and HY-115545), and drug-linker conjugates DBCO-PEG-MMAE (HY-111012 and HY-126690)[1].

  • CAS Number: 1353016-70-2
  • MF: C19H15NO3
  • MW: 305.32700
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azido-PEG9-amine

Azido-PEG9-amine is a non-cleavable 9 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1207714-69-9
  • MF: C20H42N4O9
  • MW: 482.569
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DBCO-NHS ester

DBCO-NHS ester is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1353016-71-3
  • MF: C23H18N2O5
  • MW: 402.39900
  • Catalog: ADC Linker
  • Density: 1.43±0.1 g/cm3
  • Boiling Point: 670.2±65.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: N/A

NH-bis-PEG2

NH-bis-PEG2 is a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 54384-47-3
  • MF: C8H19NO4
  • MW: 193.24
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-NH-PEG5-CH2COOH

Fmoc-NH-PEG5-CH2COOH is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 635287-26-2
  • MF: C27H35NO9
  • MW: 517.56800
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

AEEA-AEEA

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

  • CAS Number: 1143516-05-5
  • MF: C12H24N2O7
  • MW: 308.32800
  • Catalog: ADC Linker
  • Density: 1.202±0.06 g/cm3
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-Ala-Ala-PAB

Fmoc-Ala-Ala-PAB is a cleavable ADC Linker (ADC Linker). Fmoc-Ala-Ala-PAB can be used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1384263-83-5
  • MF: C28H29N3O5
  • MW: 487.55
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azido-PEG4-CH2-Boc

Azido-PEG4-CH2-Boc is a cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1]. Azido-PEG4-CH2-Boc is also a PEG- and Alkyl/ether-based PROTAC linker that can be used in the synthesis of PROTACs[2].

  • CAS Number: 864681-04-9
  • MF: C14H27N3O6
  • MW: 333.38100
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N-trifluoroacetyl-β-alanyl chloride

N-trifluoroacetyl-β-alanyl chloride is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 87639-76-7
  • MF: C5H5ClF3NO2
  • MW: 203.54700
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG7-acid

Propargyl-PEG7-acid is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2093154-00-6
  • MF: C18H32O9
  • MW: 392.44
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

NO2-SPP-sulfo

NO2-SPP-sulfo is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 663598-66-1
  • MF: C14H15N3O9S3
  • MW: 465.48
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Di-​tert-​butyl iminodiacetate

NH-bis(C1-Boc)is a uncleavable linker used for antibody-drug conjugates (ADC).

  • CAS Number: 85916-13-8
  • MF: C12H23NO4
  • MW: 245.315
  • Catalog: ADC Linker
  • Density: 1.0±0.1 g/cm3
  • Boiling Point: 298.0±25.0 °C at 760 mmHg
  • Melting Point: 38-42ºC(lit.)
  • Flash Point: 134.0±23.2 °C

Methyl azetidine-3-carboxylate hydrochloride

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

  • CAS Number: 100202-39-9
  • MF: C5H10ClNO2
  • MW: 151.591
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: 190.9ºC at 760 mmHg
  • Melting Point: 93.0 to 97.0 °C
  • Flash Point: 69.3ºC

Boc-NH-PEG4-CH2CH2NH2

Boc-NH-PEG4-CH2CH2NH2 a cleavable 5 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 811442-84-9
  • MF: C15H32N2O6
  • MW: 336.42400
  • Catalog: ADC Linker
  • Density: 1.059
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: 222 °C

Fmoc-NH-PEG3-CH2CH2COOH

Fmoc-NH-PEG3-CH2CH2COOH is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 867062-95-1
  • MF: C24H29NO7
  • MW: 443.490
  • Catalog: ADC Linker
  • Density: 1.2±0.1 g/cm3
  • Boiling Point: 651.9±55.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 348.0±31.5 °C

Me-Tet-PEG5-COOH

Me-Tet-PEG5-COOH is an ADC Linker containing 5 PEG units. Me-Tet-PEG5-COOH can utilize its own Tetrazine group to undergo a specific inverse electron demand Diels-Alder reaction (iEDDA) with compounds with TCO groups.

  • CAS Number: 2143964-72-9
  • MF: C24H35N5O8
  • MW: 521.56
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-VC-PAB-NH2

MC-vc-PAB-NH2 is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1616727-20-8
  • MF: C31H46N8O8
  • MW: 658.75
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

NO2-SPDMV-sulfo

NO2-SPDMV-sulfo is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 663599-00-6
  • MF: C15H17N3O9S3
  • MW: 479.51
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N-BOC-cis-4-Hydroxy-L-proline

N-Boc-cis-4-hydroxy-L-proline is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). N-Boc-cis-4-hydroxy-L-proline is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PROTACs[1][2

  • CAS Number: 87691-27-8
  • MF: C10H17NO5
  • MW: 231.246
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 390.9±42.0 °C at 760 mmHg
  • Melting Point: 146ºC
  • Flash Point: 190.2±27.9 °C

MC-VC-PAB-NH2 TFA

MC-VC-PAB-NH2 TFA is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1616727-21-9
  • MF: C33H47F3N8O10
  • MW: 772.77
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG2-acid

Propargyl-PEG2-acid is a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1859379-85-3
  • MF: C8H12O4
  • MW: 172.18
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Me-Tet-PEG9-COOH

Me-Tet-PEG9-COOH is an ADC Linker containing 9 PEG units. Me-Tet-PEG9-COOH can utilize its own Tetrazine group to undergo a specific inverse electron demand Diels-Alder reaction (iEDDA) with compounds with TCO groups.

  • CAS Number: 2143964-70-7
  • MF: C32H51N5O12
  • MW: 697.77
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A