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Updated: Jul 16, 2026

Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
Structure-activity relationships for abiotic thiol reactivity and aquatic toxicity of halo-substituted carbonyl
T W Schultz1, K E Ralston, D W Roberts
1Department of Comparative Medicine, College of Veterinary Medicine, The University of Tennessee, 2407 River Drive, Knoxville, TN 37996-4543, USA.
Abstract:
Using abiotic thiol reactivity (EC50) and Tetrahymena pyriformis toxicity (IGC50) data for a group of halo-substituted ketones, esters and amides (i.e. SN2 electrophiles) and related compounds a series of structure-activity relationships are illustrated. Only the alpha-halo-carbonyl-containing compounds are observed to be thiol reactive with the order I > Br > Cl > F. Further comparisons disclose alpha-halo-carbonyl compounds to be more reactive than non-alpha-halo-carbonyl compounds; in addition, the reactivity is reduced when the number of C atoms between the carbonyl and halogen is greater than one. Comparing reactivity among alpha-halo-carbonyl-containing compounds with different beta-alkyl groups shows the greater the size of the beta-alkyl group the lesser the reactivity. A comparison of reactivity data for 2-bromoacetyl-containing compounds of differing dimensions reveals little difference in reactivity. Regression analysis demonstrates a linear relationship between toxicity and thiol reactivity: log (IGC(50)(-1)) = 0.848 log (EC(50)(-1)) + 1.40; n=19, s=0.250, r2=0.926, r2(pred)=0.905, F=199, Pr > F=0.0001.
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