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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Vitamin D Related >
VD/VDR
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m-PEG11-acid

m-PEG11-acid is a non-cleavable 11 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1]. m-PEG11-acid is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[2].

  • CAS Number: 2280998-74-3
  • MF: C24H48O13
  • MW: 544.63
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-NHS Ester

Propargyl-PEG1-NHS ester is a nonclaevable 1-unit PEG linker for antibody-drug-conjugation (ADC).

  • CAS Number: 1174157-65-3
  • MF: C10H11NO5
  • MW: 225.19800
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: 36-41°C
  • Flash Point: N/A

Mal-Ph-CONH-PEG4-NHS ester

Mal-Ph-CONH-PEG4-​NHS ester is a non-cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1263044-88-7
  • MF: C26H31N3O11
  • MW: 561.54
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

MC-VC-PABC

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

  • CAS Number: 1703779-06-9
  • MF: C68H107N11O15
  • MW: 1318.64
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Fmoc-Phe-Lys(Trt)-PAB

Fmoc-Phe-Lys(Trt)-PAB is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1116085-98-3
  • MF: C56H54N4O5
  • MW: 863.05
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Cyclooctyne-O-amido-PEG3-NHS ester

Cyclooctyne-O-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: 2101206-34-0
  • MF: C23H34N2O9
  • MW: 482.52
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

DBCO-Sulfo-NHS ester

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

  • CAS Number: 1400191-52-7
  • MF: C25H21N2NaO8S
  • MW: 532.50
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Boc-Hyp-OH

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

  • CAS Number: 13726-69-7
  • 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: 123-127 °C(lit.)
  • Flash Point: 190.2±27.9 °C

Acid-PEG2-SS-PEG2-acid

Acid-PEG2-SS-PEG2-acid is a cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1807539-10-1
  • MF: C14H26O8S2
  • MW: 386.481
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 573.9±50.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 300.9±30.1 °C

DC1

DC1, an analogue of the minor groove-binding DNA alkylator CC-1065, is an antibody conjugate of cytotoxic DNA alkylators for the targeted treatment of cancer.

  • CAS Number: 169901-27-3
  • MF: C34H28ClN5O4S
  • MW: 638.14
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

D-Proline, 4-hydroxy-, methyl ester hydrochloride

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

  • CAS Number: 114676-59-4
  • MF: C6H12ClNO3
  • MW: 181.617
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: 121-123 ºC
  • Flash Point: N/A

m-PEG12-OH

m-PEG12-OH is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]. m-PEG12-OH is also a non-cleavable 12 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[2].

  • CAS Number: 2050595-03-2
  • MF: C25H52O13
  • MW: 560.67
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

(4E)-TCO-PEG4-DBCO

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

  • CAS Number: 1801863-88-6
  • MF: C38H49N3O8
  • MW: 675.81
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Azetidin-3-ol hydrochloride

Azetidin-3-ol hydrochloride is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Azetidin-3-ol hydrochloride is also a alkyl chain-based PROTAC linker that can be used in the synthes PROTAC.

  • CAS Number: 18621-18-6
  • MF: C3H8ClNO
  • MW: 109.555
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: 170.7ºC at 760 mmHg
  • Melting Point: 90-92°C
  • Flash Point: 120.4ºC

MC-Val-Cit-PAB-OH

MC-Val-Cit-PAB is a cathepsin cleavable ADC linker that is used for making antibody-drug conjugate. FDA approved drugs such as brentuximab vedotin use this linker.

  • CAS Number: 159857-80-4
  • MF: C28H40N6O7
  • MW: 572.65300
  • Catalog: ADC Linker
  • Density: 1.276
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Aminoxyacetamide-PEG3-azide

Aminoxyacetamide-PEG3-azide is a non-cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1379761-16-6
  • MF: C10H21N5O5
  • MW: 291.30
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

CL2A

CL2A is a complicated PEG8- and triazole-containing PABC-peptide-mc linker. CL2A is cleavable through pH sensitivity, giving rise to bystander effect, and binds the antibody at a cysteine residue via a disulfide bond. Labetuzumab govitecan used this linker[1].

  • CAS Number: 1846605-04-6
  • MF: C51H79N9O18
  • MW: 1106.22
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Amino-Tri-(t-butoxycarbonylethoxymethyl)-methane

Tris[[2-(tert-butoxycarbonyl)ethoxy]methyl]methylamine is a cleavable PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Amino-Tri-(t-butoxycarbonylethoxymethyl)-methane is also a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1].

  • CAS Number: 175724-30-8
  • MF: C25H47NO9
  • MW: 505.64200
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

BS3 Crosslinker disodium

BS3 Crosslinker disodium is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 127634-19-9
  • MF: C16H18N2Na2O14S2
  • MW: 572.42900
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Mc-Val-Cit-PABC-PNP

Mc-Val-Cit-PABC-PNP is a cathepsin cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

  • CAS Number: 159857-81-5
  • MF: C35H43N7O11
  • MW: 737.756
  • Catalog: ADC Linker
  • Density: 1.3±0.1 g/cm3
  • Boiling Point: 1034.5±65.0 °C at 760 mmHg
  • Melting Point: N/A
  • Flash Point: 579.4±34.3 °C

Azido-PEG4-Val-Cit-PAB-OH

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

  • CAS Number: 2055024-64-9
  • MF: C29H48N8O9
  • MW: 652.74
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

FBN33428

FBN33428, also known as Fmoc-​Phe-​Lys(Boc)​-​PAB; is a Hydrolyzable linker for making ADC conjugate. FBN33428 is useful for mkaing hydrolyzable prodrugs for delivery of anticancer drugs to metastatic cells. FBN33428 was first reported in WO 9813059. 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: 206133-42-8
  • MF: C42H48N4O7
  • MW: 720.867
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Boc-C16-COOH

Boc-C16-COOH is a non-cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs). Boc-C16-COOH is also a alkyl chain-based PROTAC linker that can be used in the synthesis of PROTACs[1]

  • CAS Number: 843666-40-0
  • MF: C22H42O4
  • MW: 370.56600
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Bis-PEG10-NHS ester

Bis-PEG10-NHS ester is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2221949-02-4
  • MF: C32H52N2O18
  • MW: 752.76
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

gmbs

GMBS is a heterobifunctional cross-linker. GMBS is often used to prepare antibody-enzyme and hapten-carrier protein conjugates.

  • CAS Number: 80307-12-6
  • MF: C12H12N2O6
  • MW: 280.233
  • Catalog: ADC Linker
  • Density: 1.5±0.1 g/cm3
  • Boiling Point: 461.3±47.0 °C at 760 mmHg
  • Melting Point: 123-129ºC
  • Flash Point: 232.8±29.3 °C

Azido-PEG3-Val-Cit-PAB-OH

Azido-PEG3-Val-Cit-PAB-OH is a cleavable 3 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2055024-65-0
  • MF: C27H44N8O8
  • MW: 608.69
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

BCN-HS-PEG2-VA-PABC-SG3199

BCN-HS-PEG2-VA-PABC-SG3199 (Compound 4) is a pyrrolobenzodiazepine that can be used as a drug linker of antibody-drug conjugates (ADC)[1].

  • CAS Number: 2126805-05-6
  • MF: C66H83N9O18S
  • MW: 1322.48
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Propargyl-PEG8-NHS ester

Propargyl-PEG8-NHS ester is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 2182601-74-5
  • MF: C24H39NO12
  • MW: 533.57
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

bisSP1

bisSP1 is an antibody drug conjugates linker[1].

  • CAS Number: 2253947-15-6
  • MF: C12H23N9O2
  • MW: 325.37
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A

Ald-Ph-amido-PEG4-propargyl

Ald-Ph-amido-PEG4-propargyl is a non-cleavable 4 unit PEG ADC linker used in the synthesis of antibody-drug conjugates (ADCs)[1].

  • CAS Number: 1969299-27-1
  • MF: C19H25NO6
  • MW: 363.40
  • Catalog: ADC Linker
  • Density: N/A
  • Boiling Point: N/A
  • Melting Point: N/A
  • Flash Point: N/A