Abstract: Carborane substituted porphyrin compounds complexed with a metal or transition metal have a variety of therapeutic uses. These compounds have been found, for example, selectively to inhibit viral aspartyl proteases. The transition metal complexes are useful both therapeutically in BNCT (boron neutron capture therapy) as well as for MR contrast enhancement. Particularly preferred compounds in accordance with the invention use the dipotassium salt of 2,4-bis-[.alpha.,.beta.-(1,2-dicarbaclosododecaborane carboxy)ethyl]deuteroporphyrin, which is complexed with a metal or a transition metal. These compounds are well solubilized in water, and are suitable for oral administration.

Abstract: A compound is described having the structure ##STR1## where R preferably is ##STR2## and most preferably R.sup.3 is a closo-carborane and R.sup.2 is --H, an alkyl or aryl having 1 to about 7 carbon atoms,This invention was made with Government support under NIH Grant No. CA-37961 awarded by the Department of Health and Human Services and under the Associated Universities Inc. Contract No. De-AC02-76CH00016 with the U.S. Department of Energy. The Government has rights in this invention.