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TCO-PNB Ester (equatorial) (CCT-1192)



TCO-PNB Ester is an amine-reactive building block used for modification of amine-containing molecule in organic media. TCO-PNB Ester is supplied as a single equatorial (major, rel-(1S-2S-5E-pR), ref 1 and 4) diastereomer. Specially formulated crystalline provides easy handling and extended shelf life.

Important Product Information:
TCO-PNB Ester is not recommended for labeling of proteins in aqueous buffers due to poor level of activation of labeled proteins (Rahim, M.K., et al., Bioconjugate Chem. 2015, 26, 352-360). TCO-PEG4-NHS Ester and TCO-PEG12-NHS Ester are well suited for protein and antibody labeling in aqueous buffers.


Unit Size25 mg, 100 mg, 100 mg
Molecular weight291.30
Chemical compositionC15H17NO5
SolubilityDMSO, DMF, DCM, THF, Chloroform
Purity>95% (HPLC)
AppearanceWhite to slightly grey solid
Storage Conditions-20°C. Desiccate
Shipping ConditionsDry ice

Selected References

  1. Royzen, M., et al. (2008). A Photochemical Synthesis of Functionalized trans-Cyclooctenes Driven by Metal Complexation. J. AM. CHEM. SOC., 130: 3760-1. [PubMed]
  2. Blackman, M.L., et al. (2008). Tetrazine ligation: fast bioconjugation based on inverse-electron-demand Diels-Alder reactivity. J. AM. CHEM. SOC., 130: 13518-9. [PubMed]
  3. Rahim, M.K., et al. (2015). Enhancing Reactivity for Bioorthogonal Pretargeting by Unmasking Antibody-Conjugated trans-Cyclooctenes. Bioconjugate Chem., 26: 352-60. [PubMed]
  4. Rossin, R., et al. (2013). Highly Reactive trans-Cyclooctene Tags with Improved Stability for Diels−Alder Chemistry in Living Systems. Bioconjugate Chem., 24: 1210-7. [PubMed]

Applicable patents and legal notices are available at legal notices.

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