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Novel Carboranyl Amino Acids and Peptides

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

Abstract

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.

Keywords

Boron Atom Amino Ester Propargyl Bromide Tetrabutylammonium Fluoride FMOC Protected Amino Acid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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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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