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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tans-4-Hydroxy-D-proline methyl ester hydrochloride

tans-4-Hydroxy-D-proline methyl ester hydrochloride is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). tans-4-Hydroxy-D-proline methyl ester hydrochloride is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PROTACs[1][2].

  • CAS Number: 481704-21-6
  • MF: C6H12ClNO3
  • MW: 181.617
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DTSSP Crosslinker

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

  • CAS Number: 81069-02-5
  • MF: C14H16N2O14S4
  • MW: 564.54200
  • Catalog: ADC Linker
  • Density: 1.94
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Glucocorticoid receptor agonist-1 phosphate Gly-Glu-Br

Glucocorticoid receptor agonist-1 phosphate Gly-Glu-Br is an ADC linker that can be used to synthesize ABBV-154, ABBV-927, ABBV-368 or their analogs[1].

  • CAS Number: 2344809-82-9
  • MF: C44H51BrN3O14P
  • MW:
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Docosanedioic acid

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

  • CAS Number: 505-56-6
  • MF: C22H42O4
  • MW: 370.566
  • Catalog: ADC Linker
  • Density: 1.0±0.1 g/cm3
  • Boiling Point: 527.0±23.0 °C at 760 mmHg
  • Melting Point: 72-80 °C(lit.)
  • Flash Point: 286.6±19.1 °C

N-Succinimidyl 6-maleimidohexanoate

6-Maleimidohexanoic acid N-hydroxysuccinimide ester(ECMS) is a useful protective group in antibody drug conjugates.

  • CAS Number: 55750-63-5
  • MF: C14H16N2O6
  • MW: 308.287
  • Catalog: ADC Linker
  • Density: 1.4±0.1 g/cm3
  • Boiling Point: 480.6±47.0 °C at 760 mmHg
  • Melting Point: 70-73 °C(lit.)
  • Flash Point: 244.5±29.3 °C

N-tert-Butoxycarbonyl-trans-4-hydroxy-D-proline

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

  • CAS Number: 147266-92-0
  • 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: 123ºC
  • Flash Point: 190.2±27.9 °C

diMal-O-CH2COOH

diMal-O-CH2COOH is a cleavable ADC linker.

  • CAS Number: 1620837-47-9
  • MF: C13H12N2O7
  • MW: 308.24
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-GGFG-NH-CH2-O-CH2-cyclopropane-COOH

MC-GGFG-NH-CH2-O-CH2-cyclopropane-COOH is an ADC linker that can be combined with the cytotoxic Camptothecin (HY-16560) to form ADC-related drug-linker conjugates (Drug-Linker Conjugates for ADC ).MC-GGFG-NH-CH2-O-CH2-cyclopropane-COOH is conjugated to Camptothecin, which can further bind to the antibody Trastuzumab (HY-P9907) to form Antibody-Drug Conjugates (ADCs)[1].

  • CAS Number: 2778374-70-0
  • MF: C31H40N6O10
  • MW: 656.68
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Bis-PEG7-NHS ester

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

  • CAS Number: 1334170-02-3
  • MF: C26H40N2O15
  • MW: 476.47488
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azido-PEG3-maleimide

Azido-PEG3-maleimide is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. Azido-PEG3-maleimide is also a cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 1858264-36-4
  • MF: C15H23N5O6
  • MW: 369.373
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Val-Cit-PAB-OSBT (GMP)

Val-Cit-PAB-OSBT GMP is a GMP grade Val-Cit-PAB-OSBT (HY-78736). Val-Cit-PAB-OSBT is a degradable ADC linker, which is composed of the polypeptide Val-Cit-PAB and OSBT groups coupled together[1].

  • CAS Number: 2210262-26-1
  • MF: C24H43N5O4Si
  • MW: 493.71
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

TCO-GK-PEG4-NHS ester

TCO-GK-PEG4-NHS ester is an ADC Linker, and can be used for synthesis of [18F]AlF-NOTA-Tz-TCO-GK-2Rs15d. [18F]AlF-NOTA-Tz-TCO-GK-2Rs15d binds with high affinity and immunoreactivity to HER2[1].

  • CAS Number: 2307311-19-7
  • MF: C33H52N4O14
  • MW: 728.78
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

sulfo-SPDB

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

  • CAS Number: 1193111-39-5
  • MF: C13H14N2O7S3
  • MW: 406.45
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

SCO-PEG3-NH2

SCO-PEG3-NH2 is a cleavable ADC Linker containing 3 PEG units. SCO-PEG3-NH2 can be used as a copper-free click chemical reagent for catalyst-free click reactions.

  • CAS Number: 2141976-29-4
  • MF: C17H30N2O5
  • MW: 342.43
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DBCO acid 2

DBCO acid 2 is a Click Chemistry intermidate used for antibody-drug conjugates.

  • CAS Number: 1207355-31-4
  • MF: C20H17NO3
  • MW: 319.354
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 635.5±55.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 338.2±31.5 °C

H2N-PEG8-CH2CH2COO<sup>t</sup>Bu

Amino-PEG8-Boc is a cleavable 8 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 756526-06-4
  • MF: C23H47NO10
  • MW: 497.62000
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DMAC-SPDB

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

  • CAS Number: 663599-05-1
  • MF: C16H19N3O5S2
  • MW: 397.47
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Mal-PEG2-Val-Cit-PABA

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

  • CAS Number: 1662687-83-3
  • MF: C27H38N6O9
  • MW: 590.63
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG3-NHS ester

Propargyl-PEG3-NHS ester is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1428629-71-3
  • MF: C14H19NO7
  • MW: 313.303
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 427.2±55.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 212.1±31.5 °C

Amino-Tri-(carboxyethoxymethyl)-methane hydrochloride

Amino-Tri-(carboxyethoxymethyl)-methane hydrochloride is a cleavable PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Amino-Tri-(carboxyethoxymethyl)-methan hydrochloride is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1][2].

  • CAS Number: 1416771-72-6
  • MF: C13H24ClNO9
  • MW: 373.78
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-Ala-Ala-PAB

MC-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: 1949793-44-5
  • MF: C23H30N4O6
  • MW: 458.51
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

SMPT

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

  • CAS Number: 112241-19-7
  • MF: C18H16N2O4S2
  • MW: 388.46100
  • Catalog: ADC Linker
  • Density: 1.43g/cm3
  • Boiling Point: 547ºC at 760mmHg
  • Melting Point: N/A
  • Flash Point: 284.6ºC

Amino-PEG11-OH

Amino-PEG11-OH is non-cleavable 11 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 15332-94-2
  • MF: C22H47NO11
  • MW: 501.61
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N-Succinimidyl 3-maleimidopropionate

BMPS is a nonclaevable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 55750-62-4
  • MF: C11H10N2O6
  • MW: 266.20700
  • Catalog: ADC Linker
  • Density: 1.55g/cm3
  • Boiling Point: 448.8ºC at 760mmHg
  • Melting Point: 168-170 °C(lit.)
  • Flash Point: 225.2ºC

Mal-PEG1-Val-Cit-PABC-OH

Mal-PEG1-Val-Cit-PABC-OH is a cleavable 1 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2055041-37-5
  • MF: C27H38N6O8
  • MW: 574.63
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-VC-PABC-Aur0101

MC-VC-PABC linker is a protease-cleavable ADC linker used in the synthesis of antibody-drug conjugates[1].

  • CAS Number: 1438849-92-3
  • MF: C68H100N12O14S
  • MW: 1341.66
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

β-D-tetraacetylgalactopyranoside-PEG1-N3

β-D-tetraacetylgalactopyranoside-PEG1-N3 is a cleavable 1 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 153252-36-9
  • MF: C18H27N3O11
  • MW: 461.42
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DBCO-NHCO-PEG4-acid

DBCO-Amide-PEG5-acid is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1870899-46-9
  • MF: C32H40N2O9
  • MW: 596.67
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

N-Succinimidyl maleimidoacetate

AMAS is a heterobifunctional crosslinker with NHS ester and maleimide groups that allows covalent conjugation of amine- and sulfhydryl-containing molecules.

  • CAS Number: 55750-61-3
  • MF: C10H8N2O6
  • MW: 252.180
  • Catalog: ADC Linker
  • Density: 1.6±0.1 g/cm3
  • Boiling Point: 430.1±47.0 °C at 760 mmHg
  • Melting Point: 174-175ºC
  • Flash Point: 213.9±29.3 °C

DBCO-PEG4-amine

DBCO-PEG4-amine is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). DBCO-PEG4-amine can be used in the synthesis of FPM-PEG4-DBCO (a homobifunctional azide-to-azide cross-linker)[1].

  • CAS Number: 1840886-10-3
  • MF: C29H37N3O6
  • MW: 523.62
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A