# BORONATED TUMOR-SEEKING PORPHYRINS--SYNTHESIS & TESTING

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA, SAN FRANCISCO · 1992 · $278,152

## Abstract

The specific aim of this work is the synthesis and biomedical
evaluation of water-soluble porphyrins and phthalocyanines
containing polyhedral borane derivatives.  The boranes to be
attached include derivatives of icosahedral neutral carboranes,
B10C2H12 and borane anions, B12H122-, and dodecahedral borane
anions, B10H102-.  Both natural and synthetic classes of porphyrins
will serve as substrates for cage attachment, while in the
phthalocyanines linkage will be effected through reactive side
groups appended to the aromatic azaporphyrin rings.  A variety of
linkage chemistries are proposed which exploit the extensive
derivative chemistries of boranes and nitrogen macrocycles.  Water
solubility in the carborane derivatives is to be achieved by
several methods including cage opening, carboxylation and
sulfonylation of the synthetic macrocycles and by beta-pyrrole
propionic acid residues in the natural porphyrin series.  The
charged borane anion derivatives are expected to be inherently
water-soluble.  Biomedical evaluation of new compounds will include
both in vitro and in vivo localization and toxicological studies
carried out in collaboration with a group at Brookhaven National
Laboratories.  In suitable cases neutron capture therapy
experimental trials in animal will follow.  The long term
objectives of the proposed work are:  (1) to prepare boronated
macrocycles which will selectively accumulate in tumor cells, and
(2) to better understand the factors which influence tumor
localization of porphyrins and phthalocyanines.  The use of boron
compounds in the treatment of human cancer is based on the unique
property of non-radioactive 10B to absorb thermal neutrons.  The
prompt nuclear fissions which ensure deliver a dose of nearly 2.8
MeV only in the vicinity of boron-containing cells since the
nuclear fragments produced (alpha particles and lithium atoms)
travel only 10-15mm.  Previous work in our laboratory has shown
that:  (1) water-soluble carboranyl porphyrins of several types can
be successfully prepared, and (2) many of these accumulate in a
model tumor system in therapeutic amounts.  One of these is a
unique porphyrin which produces sustained tumor boron levels at
least twice those of any other reported compound including the one
currently used clinically in Japan.  In light of our very
encouraging initial results in this area, funds are requested for
a significant enhancement of our efforts.

## Key facts

- **NIH application ID:** 3175944
- **Project number:** 2R01CA037961-07
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
- **SAM.gov UEI:** KMH5K9V7S518
- **Principal Investigator:** STEPHEN B KAHL
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1992
- **Award amount:** $278,152
- **Award type:** 2
- **Project period:** 1985-07-01 → 1996-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3175944

## Citation

> US National Institutes of Health, RePORTER application 3175944, BORONATED TUMOR-SEEKING PORPHYRINS--SYNTHESIS & TESTING (2R01CA037961-07). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3175944. Licensed CC0.

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