US EPA

1378688 

Technical Report 

Substituent Effects on the Binding Constants of Arsenical-Dithiol Adducts. (Reannouncement with New Availability Information) 

Dill, K; Huang, L; Mcgown, EL; Youn, SH; O'Connor, RJ 

1991 

NTIS/03005313_a 

GRA and I 

GRA and I 

A crucial and elementary factor in determining whether a compound may be an effective arsenical antidote is the association constant for the arsenic antidote adduct. This vital feature may be influenced by several parameters associated with the antidote; for example electrostatic charge, bulkiness, and electronic nature of the antidote. To further our studies dealing with the elucidation of physical and chemical factors that determine antidote efficacy (1-3), we studied the relative arsenical binding of several 'aliphatic' compounds related in structure to BAL, an arsenical topical antidote developed in the 1940's. Proton nuclear magnetic resonance spectroscopy (Hydrogen 1 NMR) was used to determine the relative binding constants for several arsenical dithiol adducts. The compounds investigated were 2,3-dimercaptopropanol (British anti-lewisite; BAL), 1,2-ethane dithiol (ET), and 1,2-propane dithiol (PDT). It was found that PDT has a significantly higher affinity than ET or BAL for phenyldichloroarsine (PDA) in methanol. 

Antidotes; Aliphatic compounds; Arsenic; Arsenic compounds; Chemical properties; Constants; Electrostatic charge; Physical properties; Reprints; Arsenic agents; *Thiols; Propanol/2; 3 dimercapto; Propanols; Antilewisite; Thiol(di)/1-2-ethane; Ethane; Propane; Thiol(di)/1-2-propane; Phenyldichloroarsine; Arsine/Phenydichloro; Binding sites; Nuclear magnetic resonance