Sodium 2, 3-dimercaptopropane-l-sulfonate

BAL is lipid soluble and it has the ability to remove metal deposits not available to attack by other chelators. More effective and less toxic compounds have since become available these include vicinal dithiols, other dithiols, aminocarboxylic acids, cysteine derivatives, and others. Unithiol (sodium 2,3-dimercaptopropane-l-sulfonate DMPS) forms very stable, water soluble complexes with Hg2+, Pb2+, Cd2+, Zn2+, Bi3+, As3+, Sb2+ and Ni2+. The complexes are nearly all less toxic than... 

Garza-Ocanas L,Torres-Alanis O, Pineyro-Lopez A. Urinary mercury in twelve cases of cutaneous mercurous chloride (calomel) exposure effect of sodium 2, 3-dimercaptopropane-l-sulfonate (DMPS) therapy. J Toxicol Clin Toxicol 1997 35(6) 653-5. 

Two compounds closely related to BAL which have been examined as arsenic antidotes for arsenic are the vicinal dithiols meso-2,3-dimercaptosuc-cinic acid (DMSA) and sodium 2,3-dimercaptopropane-l-sulfonate (DMPS) (Aposhian et al. 1984). Both of these compounds form five-membered chelate rings with typical trivalent arsenic compounds (O Connor et al. 1989). These vicinal dithiols do not have identical binding constants for trivalent arsenic. The relative order of binding (O Connor et al. 1990) is BAL DMPS > DMSA, with the binding constants for BAL and DMPS for arsenic being about ten times greater than the constant for DMSA. 

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