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Novel Carboranyl Diols and Their Derived Phosphate Esters

  • Robert R. Kane
  • Christine S. Lee
  • Cindy L. Coe
  • Melissa A. St. Rose
  • Karin Drechsel
  • M. Frederick Hawthorne

Abstract

Tumor-directed antibodies or their immunoreactive fragments are attractive candidates for the selective delivery of 10B for BNCT, provided that ~1000 10B atoms can be attached to each immunoreactive protein without significantly altering its biological properties. 1 Previous studies have revealed problems associated with randomly conjugating whole monoclonal antibodies (MAbs) with large numbers of small boron-containing compounds 2 or with limited numbers of heterogeneous 3 or homogeneous boron-rich polymers. 4 Recently, we have described an approach to this problem based on the synthesis of a homogeneous boron-rich ‘trailer’ compound and it’s conjugation to a specific site of a tumor-directed antibody fragment (Fab-SH). 5 The success of this approach rests upon the ability to precisely synthesize a hydrophilic “trailer” molecule containing ~1000 10B atoms. An oligophosphatebased boronated “trailer” is an attractive target, as the requisite coupling chemistry is well developed (in the context of DNA synthesis 6) and the polyanionic oligomers would be expected to be inherently hydrophilic. We report herein preliminary results concerning the solution-phase synthesis of hydrophilic boron-rich oligophosphates, novel compounds that may find utility as intermediates in the assembly of tumor-localizing boron-rich compounds. 7

Keywords

Selective Delivery Carborane Derivative Label Biomolecule Polyanionic Oligomer Immunoreactive Fragment 
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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Copyright information

© Springer Science+Business Media New York 1993

Authors and Affiliations

  • Robert R. Kane
    • 1
  • Christine S. Lee
    • 1
  • Cindy L. Coe
    • 1
  • Melissa A. St. Rose
    • 1
  • Karin Drechsel
    • 2
  • M. Frederick Hawthorne
  1. 1.University of California at Los AngelesLos AngelesUSA
  2. 2.On leave from Institut für Anorganische Chemie der TechnischenHochschule AachenAachenGermany

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