Novel Carboranyl Amino Acids and Peptides

  • Robert R. Kane
  • Roger H. Pak
  • Lai-Ling Ng
  • M. Frederick Hawthorne


Successful BNCT will require the selective accumulation of 5–30 ppm 10B in tumor. 1 An attractive method for the delivery of boron to tumors is an antibody-based approach, which requires that ~103 boron atoms be delivered by each immunoprotein in order to achieve the necessary 10B concentrations. This requirement presents a chemical challenge which has led us to an interest in the precise chemical synthesis of hydrophilic boron-rich ‘trailer’ molecules. 2 We previously described the synthesis of anionic nido-carborane3 containing peptides 1 and 2 (derived from amino acid 3, Figure 1), their attachment to monoclonal IgG antibodies (Mabs) against the CEA antigen, and the in vivo characterization of these immunoconjugates. 4 However, because we found the sequential coupling reactions leading to the synthesis of 1 and 2 to be prohibitively slow under solid-phase conditions, we have recently begun to explore the synthesis of similar 10B-rich peptides in solution using a ‘doubling’ approach (segment synthesis), which is described herein.


Boron Atom Amino Ester Propargyl Bromide Tetrabutylammonium Fluoride FMOC Protected Amino Acid 
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Copyright information

© Springer Science+Business Media New York 1993

Authors and Affiliations

  • Robert R. Kane
    • 1
  • Roger H. Pak
    • 1
  • Lai-Ling Ng
    • 1
  • M. Frederick Hawthorne
    • 1
  1. 1.Department of Chemistry & BiochemistryThe University of California at Los AngelesLos AngelesUSA

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