Table 1.

Dependence of esterase IC₅₀ upon sulfur oxidation state^a

Rb	Thioether			Sulfoxide			Sulfone			TFDKd
	N°c	5 min	15 min	N°	5 min	15 min	N°	5 min	15 min	N°	5 min	15 min
Porcine Esterase
4	1	20±1.4	4.5±0.2	6	970±70	270±9		N.D.e	N.D.		N.D.	N.D.
6	2	7.5±0.3	1.8±0.1	7	280±19	33±0.2	11	470±59	100±10		N.D.	N.D.
8	3	5.6±0.2	2.4±0.1	8	200±5	23±2	12	830±48	460±44	15	25±2	9.3±0.7
10	4	2.2±0.1	1.3±0.1	9	5.5±0.3	3.2±0.2	13	63±8	28±0.4		N.D.	N.D.
12	5	12±0.8	5.3±0.2	10	12±0.2	8.6±0.2	14	37±0.7	46±0.7		N.D.	N.D.
hCE1
8	3	24±2	13±1	8	30±1	5.5±0.5	12	18±1	5.4±0.8	15	65±5	30±2
hCE2
8	3	8.5±0.2	5.8±0.5	8	11±1	7.4±0.2	12	26±1	21±2	15	36±4	20±1
Rabbit Esterase
8	3	6.7±0.2	1.9±0.1	8	16±1	5.0±0.1	12	55±1	35±1	15	42±1	14±1
MsJHE wild typef
8	3	22±3			N.D.			N.D.		15	530±32
MsJHE F259I mutantg
8	3	330±57			N.D.			N.D.		15	1,600±150

^aAll values are given as the average ± the standard deviation of 3 replicates in units of nM. Incubation of enzyme and inhibitor was performed for either 5 min or 15 min before addition of substrate as described in the Experimental.

^bR refers to the number of carbon atoms in the alkyl chain as shown in Figure 1.

^cIndividual compound numbers.

^d1,1,1-trifluorododecan-2-one.

^eN.D. indicates that value was not determined.

^fIC₅₀ values were measured for Manduca sexta juvenile hormone esterase (JHE) using juvenile hormone as the substrate. Inhibitor and enzyme were incubated for 30 min prior to addition of substrate (¹⁴C juvenile hormone). Data are from Wogulis et al.³¹.

^gIC₅₀ values were measured for a M. sexta mutant JHE in which the 259 phenylalanine had been mutated to a isoleucine. Inhibitor and enzyme were incubated for 30 min prior to addition of substrate (¹⁴C juvenile hormone). Data are from Wogulis et al.³¹.