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.


Anti-infection >
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15-PGDH 5 alpha Reductase 5-Lipoxygenase Acetyl-CoA Carboxylase Acyltransferase Adenosine Deaminase Adenosine Kinase Aldehyde Dehydrogenase (ALDH) Aldose Reductase Aminopeptidase Angiotensin-converting Enzyme (ACE) ATGL ATP Citrate Lyase Carbonic Anhydrase Carboxypeptidase Cathepsin CETP COMT Cytochrome P450 Dipeptidyl Peptidase Dopamine β-hydroxylase E1/E2/E3 Enzyme Elastase Enolase FAAH FABP Factor Xa Farnesyl Transferase Fatty Acid Synthase (FAS) FXR Glucokinase GSNOR Gutathione S-transferase HCV Protease Hexokinase HIF/HIF Prolyl-Hydroxylase HIV Integrase HIV Protease HMG-CoA Reductase (HMGCR) HSP Indoleamine 2,3-Dioxygenase (IDO) Isocitrate Dehydrogenase (IDH) Lactate Dehydrogenase LXR MAGL Mineralocorticoid Receptor Mitochondrial Metabolism MMP Nampt NEDD8-activating Enzyme Neprilysin PAI-1 PDHK PGC-1α Phosphatase Phosphodiesterase (PDE) Phospholipase Procollagen C Proteinase Proteasome Pyruvate Kinase RAR/RXR Renin ROR Ser/Thr Protease SGK Stearoyl-CoA Desaturase (SCD) Thrombin Tryptophan Hydroxylase Tyrosinase Xanthine Oxidase
Neuronal Signaling >
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Vitamin D Related >
VD/VDR
Others >
Androgen Receptor Aromatase Estrogen Receptor/ERR Progesterone Receptor Thyroid Hormone Receptor Others

cis-4-Hydroxy-L-proline hydrochloride

cis-4-Hydroxy-L-proline hydrochloride is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). cis-4-Hydroxy-L-proline hydrochloride is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1][2].

  • CAS Number: 441067-49-8
  • MF: C5H10ClNO3
  • MW: 167.591
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Amino-PEG6-alcohol

Amino-PEG6-OH is a non-cleavable 6 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 39160-70-8
  • MF: C12H27NO6
  • MW: 281.346
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 388.0±37.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 188.5±26.5 °C

NH2-PEG6-CH2CH2COOH

NH2-PEG6-CH2CH2COOH is a cleavable 6 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 905954-28-1
  • MF: C15H31NO8
  • MW: 353.40900
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Cyclooctyne-O-amido-PEG2-NHS ester

Cyclooctyne-O-amido-PEG2-NHS ester is a non-cleavable 2 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2101206-22-6
  • MF: C21H30N2O8
  • MW: 438.47
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Me-Tet-PEG3-NHBoc

Me-Tet-PEG3-NHBoc is an ADC Linker containing 3 PEG units. Me-Tet-PEG3-NHBoc can utilize its own Tetrazine group to undergo a specific inverse electron demand Diels-Alder reaction (iEDDA) with compounds with TCO groups.

  • CAS Number: 2141976-32-9
  • MF: C24H36N6O6
  • MW: 504.58
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG8-NH2

Propargyl-PEG8-NH2 (compound 3b) is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1196732-52-1
  • MF: C19H37NO8
  • MW: 407.499
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 477.4±40.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 232.8±21.0 °C

(R)-8-Azido-2-(Fmoc-amino)octanoic acid

(R)-8-Azido-2-(Fmoc-amino)octanoic acid is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1191429-18-1
  • MF: C23H26N4O4
  • MW: 422.48
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Me-Tet-PEG3-Maleimide

Me-Tet-PEG3-Maleimide is an ADC Linker containing 3 PEG units. Me-Tet-PEG3-Maleimide can utilize its own Tetrazine group to undergo a specific inverse electron demand Diels-Alder reaction (iEDDA) with compounds with TCO groups. Its maleimide group (-Maleimide) degrades in aqueous media and has been used in drug delivery studies.

  • CAS Number: 2141976-31-8
  • MF: C26H33N7O7
  • MW: 555.58
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-Gly-Gly-Phe-Gly-PAB-PNP

MC-Gly-Gly-Phe-Gly-PAB-PNP is a linker for synthesis anti-human EGFR antibody drug conjugate[1].

  • CAS Number: 2632342-16-4
  • MF: C39H41N7O12
  • MW: 799.78
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Me-Tet-PEG4-COOH

Me-Tet-PEG4-COOH is an ADC Linker containing 4 PEG units. Me-Tet-PEG4-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: 2141976-30-7
  • MF: C22H31N5O7
  • MW: 477.51
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

BnO-PEG6-OH

BnO-PEG6-OH is a non-cleavable 6 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 24342-68-5
  • MF: C19H32O7
  • MW: 372.453
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 473.6±40.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 240.3±27.3 °C

Sulfo-SPDP-C6-NHS sodium

Sulfo-SPDP-C6-NHS sodium is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 169751-10-4
  • MF: C18H22N3NaO8S3
  • MW: 527.56700
  • Catalog: ADC Linker
  • Density: 1.53g/cm3
  • Boiling Point: N/A
  • Melting Point: 185-187ºC
  • Flash Point: N/A

Hydroxy-PEG4-(CH2)2-Boc

Hydroxy-PEG4-(CH2)2-Boc is a uncleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Hydroxy-PEG4-(CH2)2-Boc is extracted from patent WO2004008101A2 (compound 191).

  • CAS Number: 518044-32-1
  • MF: C15H30O7
  • MW: 322.39500
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DBCO-PEG4-DBCO

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

  • CAS Number: 2182601-68-7
  • MF: C48H50N4O8
  • MW: 810.93
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Bis-sulfone-PEG3-Azide

Bis-sulfone-PEG3-Azide is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 1802908-01-5
  • MF: C33H40N4O9S2
  • MW: 700.82
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

(2S,4S)-1-tert-Butyl 2-methyl 4-hydroxypyrrolidine-1,2-dicarboxylate

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

  • CAS Number: 102195-79-9
  • MF: C11H19NO5
  • MW: 245.272
  • Catalog: ADC Linker
  • Density: 1.2±0.1 g/cm3
  • Boiling Point: 335.2±42.0 °C at 760 mmHg
  • Melting Point: 82-86ºC
  • Flash Point: 156.6±27.9 °C

DBCO-​C6-​acid

DBCO-C6-acid is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). DBCO-C6-acid can be used in the synthesis of carmaphycin analogues[1].

  • CAS Number: 1425485-72-8
  • MF: C21H19NO3
  • MW: 333.380
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 634.4±55.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 337.5±31.5 °C

Amino-PEG9-acid

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

  • CAS Number: 1191079-83-0
  • MF: C21H43NO11
  • MW: 485.566
  • Catalog: ADC Linker
  • Density: 1.1±0.1 g/cm3
  • Boiling Point: 578.3±50.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 303.6±30.1 °C

6-Azido-hexylamine

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

  • CAS Number: 349553-73-7
  • MF: C6H14N4
  • MW: 142.20200
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

SPDP-dPEG

LC-PEG8-SPDP is a cleavable ADC linker used for the antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1252257-56-9
  • MF: C31H49N3O13S2
  • MW: 735.863
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-NH-PEG2-CH2CH2COOH

Fmoc-NH-PEG2-CH2CH2COOH is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 872679-70-4
  • MF: C22H25NO6
  • MW: 399.437
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 622.1±55.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 330.0±31.5 °C

Hydroxy-PEG2-(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: 133803-81-3
  • MF: C11H22O5
  • MW: 234.28900
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azido-PEG4-C2-acid

Azido-PEG4-C2-acid a PEG-based PROTAC linker can be used in the synthesis of vRucaparib-TP4. Azido-PEG4-C2-acid is also a non-cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 1257063-35-6
  • MF: C11H21N3O6
  • MW: 291.30100
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

rel-1-((1R,8S,9s)-Bicyclo[6.1.0]non-4-yn-9-yl)-3-oxo-2,7,10,13,16-pentaoxa-4-azanonadecan-19-oic acid

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

  • CAS Number: 1881221-47-1
  • MF: C22H35NO8
  • MW: 441.52
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

vc-PAB-DMEA-PNU159682

vc-PAB-DMEA-PNU159682 (compound I.47) can be used to synthesize the ADC molecule based on Sulfomaleimide-based Linker. vc-PAB-DMEA-PNU159682 has good serum stability[1].

  • CAS Number: 2227350-96-9
  • MF: C56H72N8O19
  • MW: 1161.21
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

THP-PEG7

THP-PEG6-OH is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. THP-PEG6-OH is also a non-cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 42607-87-4
  • MF: C17H34O8
  • MW: 232.23900
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

TKN87180

TKN87180 is a Hydrolyzable linker for making ADC conjugate. TKN87180 was first reported in Bioorganic & Medicinal Chemistry Letters (2004), 14(16), 4323-4327. This product has not formal name. For the convenience of scientific communication, we named it by combining its Inchi key (3 letters from the first letter of each section) with the last 5 digits of its CAS number or its molecule weight if its CAS number is not available.

  • CAS Number: 756487-18-0
  • MF: C37H49N5O8
  • MW: 691.826
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

CL2A-SN-38

CL2A-SN-38, SN-38 (topoisomerase-I inhibitor) derivative, is a peptide linker. CL2A-SN-38 is conjugated to the anti-Trop-2-humanized antibody, SN-38-anti-Trop-2 antibody-drug conjugate (ADC) against several human solid tumor types, provides significant and specific antitumor effects against a range of human solid tumor types[1].

  • CAS Number: 1279680-68-0
  • MF: C73H97N11O22
  • MW: 1480.61
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Boc-Val-Ala-PAB-PNP

Boc-Val-Ala-PAB-PNP is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1884578-00-0
  • MF: C27H34N4O9
  • MW: 558.58
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-Val-Ala-OH

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

  • CAS Number: 1342211-31-7
  • MF: C18H27N3O6
  • MW: 381.42
  • Catalog: ADC Linker
  • Density: 1.232±0.06 g/cm3(Predicted)
  • Boiling Point: 695.4±50.0 °C(Predicted)
  • Melting Point: N/A
  • Flash Point: N/A