Jj. Sorci et Dl. Macalady, QUANTITATIVE STRUCTURE-ACTIVITY-RELATIONSHIPS IN BACTERIAL AND ABIOTIC ALKALINE HYDROLYZES OF PARASUBSTITUTED ACETANILIDES, Journal of agricultural and food chemistry, 41(10), 1993, pp. 1760-1766
Quantitative structure-activity relationships were established for bac
terial and abiotic alkaline hydrolysis of acetanilide, 4-bromoacetanil
ide, 4-cyanoacetanilide, 4-fluoroacetanilide, 4-methoxyacetanilide, 4-
methylacetanilide, and 4-nitroacetanilide. The influence of ring subst
ituents on hydrolysis rates was investigated using alkaline solutions
and pure bacterial cultures isolated from soil. For an Arthrobacter sp
ecies, second-order rate constant, k(b), for bacterial hydrolysis rang
ed from (1.09 +/- 0.01) x 10(-14) to (2.62 +/- 0.03) X 10(-14) L organ
ism-1 s-1 for 4-cyanoacetanilide and acetanilide, respectively, showin
g little sensitivity to substituent effects. Acetanilides were hydroly
zed to the corresponding anilines. Regression Of log k(b) with van der
Waals radii of individual substituents yielded a correlation coeffici
ent (r2) of 0.904. Substituent size and geometry, rather than any elec
tronic property, infuenced biologically mediated hydrolysis rates. Alk
aline hydrolysis rates were controlled by electronic effects (r2 = 0.8
47). Biotic and abiotic hydrolysis rates did not correlate (r2 = 0.37)
, indicating these processes are controlled by different parameters.