Click Chemistry

TCO-PEG2-NHS ester serves as a heterobifunctional PEG linker comprised of a TCO click chemistry handle that readily reacts with tetrazine groups and NHS ester that directly and efficiently reacts with amine-bearing molecules. The PEG spacer imparts water solubility.

t-Boc-N-MMAF

Biotin-PEG11-NHCO-MMAF-N-t-Boc functions as a biotinylation reagent with the biotin moiety linked to an MMAF payload protected by a Boc group which can be removed under acidic conditions to reveal the free amine. The connecting PEG arm enhances the water-solubility of the compound.

Exatecan-2-(aminomethoxy)acetamide-Gly-Phe-Gly-Gly-PEG2-endo-BCN represents a tetrapeptide derivative which may be employed in the development of antibody drug conjugates (ADCs). The BCN group is a click chemistry handle which readily reacts with azide groups on a target molecule. Exatecan is a structural analog of camptothecin and shows anticancer activity. The PEG2 spacer imparts hydrophilicity.

DBCO-PEG-2-Val-Cit-PAB-OH constitutes a cleavable ADC linker. The Val-Cit was designed specifically to be cleaved by Cathepsin B. The DBCO moiety engages in copper-free catalyzed click chemistry with azido-bearing moieties.

Fmoc-Ala-Ala-Asn is a Fmoc-protected tripeptide linker employed for ADC conjugation. It contains a cleavable Ala-Ala-Asn peptide sequence.

9-Oxoheptadecanedioic acid

Azido-PEG4-Val-Ala-PAB-Exatecan serves as a cathepsin-cleavable Val-Ala dipeptide conjugated to an exatecan payload, a structural analog of camptothecin. The terminal azido partakes in click chemistry reactions with DBCO, BCN, and linear alkynes.

Azido-PEG4-Val-Ala-PAB-SN38 serves as a cleavable ADC linker featuring a cleavable Val-Cit dipeptide, a PAB group, and an SN38 warhead. The PEG linker improves the solubility of the compound. The azide moiety can perform click chemistry reactions with BCN, DBCO, and linear alkynes.