Micellar-accelerated hydrolysis of organophosphate and thiophosphates by pyridine oximate

Article abstract of DOI:10.1002/kin.21217

Rate constants for the hydrolysis reaction of phosphate (paraoxon) and thiophosphate (parathion, fenitrothion) esters by oximate (pyridinealdoxime 2-PyOx^? and 4-PyOx^?) and its functionalized pyridinium surfactants 4-(hydroxyimino) methyl)-1-alkylpyridinium bromide ions (alkyl?=?C_nH_2n+1, n?=?10, 12, 14, 16) have been measured kinetically at pH 9.5 and 27°C in micellar media of cationic surfactants cetyltrimethylammonium bromide (CTAB) and cetylpyridinium bromide (CPB). Acid dissociation constant, pK_a, of oximes has also been determined by spectrophotometric, kinetic, and potentiometric methods. The rate acceleration effects of cationic micelles have been explored. Cationic micelles of the pyridinium head group (CPB) showed a large catalytic effect than the ammonium head group (CTAB). The effects of pH, oximate concentration, and surfactants have been discussed.

Full text of DOI:10.1002/kin.21217

Received: 22 November 2017
DOI: 10.1002/kin.21217
Revised: 20 August 2018
Accepted: 20 August 2018
A R T I C L E
Micellar-accelerated hydrolysis of organophosphate
and thiophosphates by pyridine oximate
Neha Kandpal1
Hitesh K. Dewangan1
Rekha Nagwanshi2
Kallol K. Ghosh1
Manmohan L. Satnami1
1School of Studies in Chemistry, Pt. Ravis-
hankar Shukla University, Raipur, India
Abstract
Rate constants for the hydrolysis reaction of phosphate (paraoxon) and thiophos-
2Department of Chemistry, Govt. Madhav
−
phate (parathion, fenitrothion) esters by oximate (pyridinealdoxime 2-PyOx and
Science P. G. College, Ujjain, India
Correspondence
−
4-PyOx ) and its functionalized pyridinium surfactants 4-(hydroxyimino) methyl)-
Manmohan L. Satnami, Schoolof Studiesin
Chemistry, Pt. Ravishankar ShuklaUniversity,
Raipur 492 010, India.
1-alkylpyridinium bromide ions (alkyl = CnH2n+1, n = 10, 12, 14, 16) have been
◦
measured kinetically at pH 9.5 and 27 C in micellar media of cationic surfactants
Email: manmohanchem@gmail.com
cetyltrimethylammonium bromide (CTAB) and cetylpyridinium bromide (CPB). Acid
Fundinginformation
dissociation constant, pK , of oximes has also been determined by spectrophotomet-
a
DST-FIST, Grant/AwardNumber: grantNo.
SR/FST/CSI-259/2014(C);UniversityGrants
Commission(U.G.C.), NewDelhi, Research
award(2016–18), Grant/AwardNumber:
grant(No. 30-1/2015 (SA-II);UGC-SAP,
Grant/AwardNumber:UGC-SAP Grant
No. F-540/7/DRS- II/2016 (SAP-I);Chhat-
tisgarhCouncil of ScienceandTechnology
(CCOST), Grant/AwardNumber: (Grant No.
1104/CCOST/MRP/15, Raipur, 2015)
ric, kinetic, and potentiometric methods. The rate acceleration effects of cationic
micelles have been explored. Cationic micelles of the pyridinium head group (CPB)
showed a large catalytic effect than the ammonium head group (CTAB). The effects
of pH, oximate concentration, and surfactants have been discussed.
K E Y W O R D S
cationic micelles, functionalized surfactants, oximate, phosphate esters
compounds of low polarity and their chemical decontamina-
tion is less effective in aqueous media.9,10 The investigation
1
INTRODUCTION
of the ꢀ-nucleophiles for the detoxification of organophospho-
rus pesticides has received major attention due to their supe-
rior reactivity as compared to normal nucleophiles. Oximes
because of their ꢀ-effect nucleophilic reactivity and a profi-
cient approach to weaken toxicity are used as antidotes for the
reactivation of organophosphorus pesticides.11,12 Phosphate
esters, for the most part mono- and diesters, are ever-present
in nature and are fundamental segments of coenzymes, heredi-
tary materials, vitality repositories, and so on. Because of the
biological consequence of these esters, their ecological evi-
dences and degradation have been broadly examined over the
previous decades.13–17
A flexible and rapid decontamination method has been
devoted for detoxifying persistent organophosphorus pesti-
cides as well as a chemical warfare agent over the past sev-
eral decades.1,2 Both pesticides and chemical warfare agents
inhibit the serine moiety of the enzyme acetylcholinesterase
and deactivate its capacity with significant impacts on the
nervous system.3 The inhibition results in life-endangering
impairments on the human body such as cholinergic disorder,
respiratory failure, and ultimately leading to death. Oximate
−
−
(Ox ) and hydroxamate (HA ) were proved to be strong reac-
tivators of acetylcholinesterase enzymes and play an impor-
tant role as dephosphorylating agent toward the organophos-
phate esters.4 A promising strategy incorporates the removal
of phosphoryl moiety from the active site of AChE and
restores the activity of enzyme. Functionalized surfactants are
among the most powerful and efficient reagents for the detoxi-
fication of organophosphorus pesticides because of their high
solubilizing power5–8 and high polarity, but pesticides are
Over the past several years, efforts have been made to
develop a huge number of mono- and bispyridinium oximes,
which are a vital group of medications utilized as a rem-
edy for the treatment of profoundly harmful organophospho-
rus compounds.18–20 Voicu and his group21 designed some
oximes reactivators to enhance BBB (blood brain barrier)
Int J Chem Kinet. 2018;1–9.
wileyonlinelibrary.com/journal/kin
© 2018 Wiley Periodicals, Inc.
1

2
KANDPAL ET AL.
SCHEME 1 Reaction of phosphate esters with
oximes in micellar media [Color figure can be
viewed at wileyonlinelibrary.com]
penetration. Recently, Ghosh and co-workers22 present an
excellent article, which describes the design and synthesis
of different metallosurfactant aggregates as catalysts for the
hydrolysis of carboxylate and phosphate esters. Toullec and
Moukawim23 reported cetyltrimethylamrnonium hydroperox-
ide as an efficient reagent for promoting phosphate ester
hydrolysis. Simanenko and co-workers24 synthesized imida-
zolium halides, which are functionalized zwitterionic sur-
factants and give rise to micelle formation. Biresaw and
Bunton25 described a stepwise self-association model and
observed that bimolecular rates in water and “organized
assemblies” are usually similar, where “catalysis” by micelles
and other organized assemblies are due to the concentra-
tion effect. Similarly, Hampl et al.26 discussed how struc-
ture and lipophilicity of functionalized surfactants influ-
ence their reactivity in micelles and microemulsion. They
proved that the lipophilicity is the most important factor
influencing the localization and reactivity of functionalized
surfactants in nanoaggregates. Cuccovia and co-workers27
determined the effects of micelles and vesicles on the rate
of oximolysis of p-nitrophenyldiphenyl phosphate and a
model system for surfactant-based skin defensive formula-
tions against organophosphates. Here, we have investigated
2
MATERIALS AND METHODS
2.1 Materials
Paraoxon, parathion, CTAB, CPB, 4-pyridinealdoxime
(4-PyOx), and 2-pyridinealdoxime (2-PyOx) were obtained
from Sigma/Aldrich (Bangalore, India). Quaternized
oxime, 4-hydroxyiminomethyl-1-alkyl pyridinium bromide
(alkyl = CnH2n+1 n = 10, 12), was prepared according to
the literature method.28 Water used for the preparation of
samples was deionized and triply distilled.
2.2 Methods
2.2.1 Determination of acid dissociation
constant (pKa)
The acid dissociation constants (pK ) values of all the differ-
a
ent oxime-based functionalized surfactant 4-(hydroxyimino)
methyl)-1-alkylpyridinium bromide ions (alkyl
=
−
−
−
−
4-C10PyOx , 4-C12PyOx , 4-C14PyOx , 4-C16PyOx )
were determined by potentiometric, kinetic, and spectropho-
tometric methods.
the acid dissociation constant (pK ) and hydrolytic efficacy
a
of oximes and oxime-functionalized pyridinium surfactant
4- hydroxyiminomethyl-1-alkylpyridinium bromide (alkyl
chain length dodecyl, 4-C12 and decyl, 4-C10) toward
the cleavage of phosphate (paraoxon) and thiophosphate
(parathion and fenitrothion) esters in the presence of cationic
surfactants cetyltrimethylammonium bromide (CTAB) and
cetylpyridinium bromide (CPB) (Scheme 1).
2.2.2 Potentiometric method
The acidity constant (pK ) values of oximes were calculated
a
◦
at 27 C by the potentiometric titration method using an Orion
Star A-211 pH-meter (Figure 1). All functionalized oximes
were titrated with 0.01 M NaOH, and the ionic strength was
maintained constant at 0.1 M by adding KCl. The pK values
a

KANDPAL ET AL.
3
−
−
−
−
F I G U R E 1 Determination of acid dissociation constant (pK ) of (A) 4-C10PyOx , (B) 4-C12PyOx , (C) 4-C14PyOx , and (D) 4-C16PyOx
a
[Color figure can be viewed at wileyonlinelibrary.com]
were calculated by means of Equation 1 from the measured
pH values of the solution:
functionality. The calculations of pK were made around half
neutralization using the following eqauation:
Absꢅ − AbsH
−
ox
[
]
A
pꢁa = pHexp − log
(2)
pꢁꢂ = pH − log
(1)
Absox − Absꢅ
[ꢃꢄ]
where AbsHOx is the absorbance of the unionized form of
oxime, Absꢅ is the absorbance of the partially ionized form
of oxime, and AbsOx is the absorbance of fully ionized form
2.2.3 Spectrophotometric method
−
of oxime. The absorbance at 340 nm for [4-C10PyOx ] was
The pK values of all the functionalized oximes were deter-
mined sapectrophotometricaly using a Thermofisher Evolution
300 UV-Visible spectrophotometer equipped with a temper-
ature controller (Peltier) by using a well-known method of
Albert and Sergeant.29 It is based on direct determination of
the ratio of protonated to deprotonated species in buffer solu-
tions. An aliquot (3 mL) of a stock solution (5 × 10–4 M)
of functionalized oxime in triple-distilled water was diluted
with a 25-mL phosphate buffer solution. The absorption spec-
trum was recorded in the range of 200–600 nm and at dif-
ferent pH values. Different pH values ranging from 6.01 to
10.50 were maintained using different compositions of phos-
phate buffer. After each pH adjustment, the solutions were
transferred into the cuvette and the absorption spectra were
recorded. The average values of 10 measurements were con-
plotted against the pH of the buffer solutions. The sigmoidal
curves (Figure 2) were obtained, and pK values were cal-
culated based on their determinations araound the point of
half neutralization using Equation 2. pK values of func-
tionalized oxime (4-hydroxyiminomethyl-1a -alkylpyridinium
bromide) are presented in Table 1, which are quite well in
agreement with the literature values.30 The spectrophotomet-
−
ric determination of pK of oxime [4-C10PyOx ] is shown in
a
Figure 3.
2.2.4 Kinetic method
The apparent pK values of some oxime-based functionalized
a
nucleophiles have been determined by measuring the first-
order rate constant for the hydrolysis of paraoxon at different
pH values (6–10) in the presence of functionalized oximes.
sidered as the pK of the compound with respect to oxime
a

4
KANDPAL ET AL.
F I G U R E 3 Spectrophotometric determination of pK of oxime
a
−
F I G U R E 2 Plot between absorbance (340 nm) and pH for
[4-C10PyOx ] of oxime [Color figure can be viewed at
−
4-hydroxyiminomethyl-1-decylpyridinium bromide [4-C10PyOx ]
[Color figure can be viewed at wileyonlinelibrary.com]
wileyonlinelibrary.com]
TA B L E 1 Acid dissociation constants (pK ) of functionalized
a
surfactants (4-hydroxyiminomethyl-1-alkyl pyridiniumbromide) with
alkyl chain lengths (C10, C12, C14, C16) determined by kinetic,
potentiometric, and spectrophotometric methods
pKa
Functionalized Kinetic Potentiometric Spectrophotometric
surfactant
4-C10PyOx
4-C12PyOx
4-C14PyOx
4-C16PyOx
method method
method
9.34
9.20
8.71
8.16
_
9.18
8.60
8.12
7.91
9.18
8.55
8.32
The data indicate that the rate of reaction increases with an
F I G U R E 4 Plots of log k versus pH for the cleavage of
obs
increase in pH values. Figure 4 shows the plots of log k
versus pH at different pH values. The pK values obtainedobbys
paraoxon in the presence of 4 hydroxyiminomethyl-1-alkylpyridinium
a
bromide (C10 and C12 and C14). Reaction conditions: [paraoxon] =
the kinetic method agreed well with those measured by the
spectrophotometeric and conductometric methods (Table 1).
−4
−3
1 × 10 M, [4-Cn] = 1 × 10 M, [KCl] = 0.1 M, [CTAB] = 1.0 mM,
◦
temperature = 27 C [Color figure can be viewed at
wileyonlinelibrary.com]
2.3 Kinetic treatment
spectra at 400 nm with an increase in absorbance of the
p-nitrophenoxide ion for the hydrolysis of paraoxon with
4-C10PyOx at 1.0 mM CTAB.
The pseudo–first-order rate constants for the hydrolysis of
phosphate esters in the presence of oxime-based function-
◦
alized surfactants were determined at 27 C by monitoring
the formation of the p-nitrophenoxide anion at wavelength
400 nm using a Thermofisher Evolution 300 UV–visible
spectrophotometer equipped with a temperature controller
(Peltier). Rate constants for the cleavage of phosphate esters
by oximes were determined at an ionic strength of 0.1 M
KCl. Borate buffer was employed to control the pH of the
reaction media. All reactions were conducted under pseudo–
first–order conditions. The pseudo–first-order rate constants
(kobs) were determined by the least-squares fit method. The
intercept were negligible. Figure 5 shows the UV–visible
3
RESULTS AND DISCUSSION
The effects of pH, nucleophile, and surfactants were eval-
uated on the kinetic behavior of pyridinium-based func-
tionalized surfactants. It can be noted that a pyridinium
surfactant is an efficient supernucleophile for the cleav-
age of various phosphate esters in micellar medium. The
study aimed at cleavage of phosphate esters (paraoxon,

KANDPAL ET AL.
5
SCHEME 2 Deprotonation of pyridinium oxime
The ionized form of oxime (−CH=NOH), i.e., the oxi-
−
mate ion (−CH=NO ), plays a significant role in the cleav-
age of phosphate esters. The data on the effect of pH on
the hydrolysis of paraoxon, parathion, and fenitrothion with
−
oximate and its functionalized oximate (4-C PyOx ) in the
presence of CTAB micelles are presented nin Tables S1–
S3 in the Supporting Information. Under comparable con-
ditions, oximate ions showed the highest reactivity toward
paraoxon as compared to other substrates due to the dif-
ference in electrophilic centers from carbonyl to sulfonyl
or phosphonyl group (P=O and P=S). As shown in the
data obtained in Table 2, paraoxon (P=O) with high elec-
trophilicity shows more reactivity than fenitrothion (S=O)
with low electrophilicity because of the poorer electron-
donating ability of thioanion in ejecting the leaving group
as compared to oxyanion. Also, the electrophilicity of the
central atom P of P=O center diminishes, which hin-
ders the attack of ꢀ-nucleophile in the rate-determining
step.32
F I G U R E 5 UV–visible spectra for the cleavage of paraoxon with
−
4-C10PyOx in cationic micellar media at different reaction times.
−4
−
−3
Reaction conditions: [Paraoxon] = 1 × 10 M, [Nu ] = 1 × 10 M,
[KCl] = 0.1 M, borate buffer pH 9.2, [CTAB] = 1.0 mM,
◦
temperature = 27 C [Color figure can be viewed at
wileyonlinelibrary.com]
parathion, and fenitrothion) with pyridinium-functionalized
surfactants. The rate constants for the hydrolysis of phos-
phate esters (paraoxon, parathion, and fenitrothion) by oxi-
−
−
mate (2-PyOx and 4-PyOx ) and functionalized oximate,
4-hydroxyimminomethyl 1-alkyl pyridinium bromide, were
◦
determined at 27 C in the presence of CTAB by employing
different buffers (phosphate and borate) ranging from pH 7 to
11 as added to the reaction medium. The pH-dependent rate
constants increase with increasing pH (7–12) in the presence
of cationic surfactant CTAB, which is shown in Figure 6. Con-
sequently, the oxime group dissociates and forms the oximate
ion, which acts as an ꢀ- nucleophile and shows drastic change
To determine the efficiency of oximes and functionalized
oximes, the rate of hydrolysis of phosphate esters on the first-
order rate constants has been studied in various concentrations
of different alkyl chain lengths (C10–C14) in CTAB at pH 9.5.
The results are summarized in Tables S4–S6 in the Support-
ing Information. Variation in the surfactant chain length has
−
at pH > pK [Ref. 31] and hence proved that 4-C14PyOx
a substantial effect on k values for the reaction of phos-
obs
+ CTAB toabe the most efficient system for ester cleavage
because of its lower pKa (8.16), which plays a significant role
in the hydrolysis of phosphate ester (Scheme 2).
phate esters (Table 3 and Figure 7). For the hydrolysis of phos-
phate esters, 4-C14 was found to be the most reactive sys-
tem and the rate constants increase with an increase in the
F I G U R E 6 pH rate profiles for the reaction of oximate and functionalized oximate ions with (A) paraoxon, (B) parathion, and (C)
−
◦
fenitrothion. Reaction conditions: [substrate] = 1 × 10–4 M, [Nu ] = 1 × 10–3 M, [CTAB] = 1.0 mM, ꢆ = 0.1 M KCl, pH 9.5, temperature = 27 C
[Color figure can be viewed at wileyonlinelibrary.com]

6
KANDPAL ET AL.
TA B L E 2 Kinetic rate data for the reaction of phosphate esters with oximate and functionalized oximate ions in the presence of cationic
surfactants [CTAB]
104 kobs (s−1
)
Substrate
Paraoxon
4-C14PyOx−
7.44
4-C12PyOx−
6.41
4-C10PyOx−
5.42
2-PyOx−
3.69
0.18
0.01
◦
4-PyOx−
3.19
Parathion
Fenitrothion
0.28
0.24
0.22
0.15
0.08
0.08
0.09
0.02
Reaction conditions: [Substrate] = 1 × 10–4 M, [Nu ] = 1 × 10–3 M, [CTAB] = 1.0 mM, ꢆ = 0.1 M KCl, pH 9.2, temperature = 27 C.
−
TA B L E 3 Effect of alkyl chain length for the hydrolysis of phosphate esters
Paraoxon
Parathion
Fenitrothion
104 kobs (s−1
)
105 kobs (s−1
)
106 kobs (s−1
)
[Nu-] (mM)
4-C12PyOx−
0.85
4-C10PyOx−
0.85
4-C12PyOx−
0.62
4-C10PyOx−
0.62
4-C12PyOx−
0.45
4-C10PyOx−
0.45
0.0
0.5
0.8
1.0
2.0
3.0
4.0
4.21
3.34
1.65
1.39
0.71
0.74
5.55
4.34
2.23
1.95
0.82
0.88
6.41
5.42
2.48
2.29
0.89
0.95
8.21
7.12
3.44
2.97
1.12
1.22
8.44
8.22
4.02
3.54
1.23
1.35
8.79
8.38
4.32
3.91
1.32
1.42
Reaction conditions: [substrate] = 1 × 10–4 M, [Nu ] = 1 × 10–3 M, [CTAB] = 1.0 mM, ꢆ = 0.1 M KCl, pH 9.5, temperature = 27 C.
−
◦
F I G U R E 7 Rate surfactant concentration profile for the reaction of oximate and functionalized oximate ions in (A) paraoxon, (B) parathion,
−
and (C) fenitrothion. Reaction conditions: [substrate] = 1 × 10–4 M, [Nu ] = 1 × 10–3 M, [CTAB] = 1.0 mM, ꢆ = 0.1 M KCl, pH 9.5,
◦
temperature = 27 C [Color figure can be viewed at wileyonlinelibrary.com]
alkyl chain length of functionalized surfactants in the follow-
ing order: 4-C14 > 4-C12 > 4-C10. It is mainly explained on
the basis of hydrophobicity, electrical surface potential of the
micelle, and also due to steric hindrance. 4-C14 possesses the
least steric hindrance and due to this reason it shows higher
reactivity.33
surfactants the reaction rate also increases at a fixed concen-
tration of nucleophile because of the transfer of nucleophile
into the micellar pseudophase and then decreases with further
addition of the surfactants due to the dilution of nucleophile
at micellar-catalyzed reactions.34 It is well known that the
micelles bring reactants closer because of electrostatic attrac-
tion of the nucleophile and hydrophobically binding of the
substrate. The extent of micellar catalysis is expected to be
depending on the relative amount of substrate incorporated in
micelles.
There have been a large number of reports on the effect
of surfactant on the rate of ester cleavage by using various
substrates and oximes. The cleavage of phosphate esters with
oximate ions in the presence of cationic surfactants CTAB
and CPB at pH 9.5 is clearly manifested in Figures 8 and 9
and in Tables S7 and S8 in the Supporting Information. The
By comparing the head group of various surfactants, the
rate constants were found to be higher with a surfactant hav-
ing an aromatic group, that is CPB has more catalytic activity
as compared to CTAB. The order of reactivity is in the fol-
lowing order: CPB > CTAB. that is the surfactant having a
k
values for the reactions in the micellar system are eval-
uoabtsed through k versus surfactant concentration profiles. It
obs
can be observed that with an increase in the concentration of

KANDPAL ET AL.
7
−
−
−
−
F I G U R E 8 Effect of surfactants on reaction of paraoxon with (A) 4-C14PyOx , (B) 4-C12PyOx , (C) 4-C10PyOx , and (D) 4-PyOx in the
−4
−
−3
presence of cationic surfactant. Reaction conditions: [paraoxon] = 1.0 × 10 M, [Ox ] = 1.0 × 10 M, pH 9.5, ꢆ = 0.1 M KCl,
◦
temperature = 27 C [Color figure can be viewed at wileyonlinelibrary.com]
−
−
−
−
F I G U R E 9 Effect of surfactants on reaction of parathion with (A) 4-C14PyOx , (B) 4-C12PyOx , (C) 4-C10PyOx , and (D) 4-PyOx in the
−4
−
−3
presence of cationic surfactant. Reaction conditions: [parathion] = 1.0 × 10 M, [Ox ] = 1.0 × 10 M, pH 9.5, ꢆ = 0.1 M KCl,
◦
temperature = 27 C [Color figure can be viewed at wileyonlinelibrary.com]

8
KANDPAL ET AL.
bulky head group and with the aromatic ring showed higher
reactivity than alkyl ammonium head groups.
6. Liu X, Dong L, Fang Y. Synthesis and self-aggregation of a
hydroxyl-functionalized imidazolium-based ionic liquid surfac-
tant in aqueous solution. J Surfactants Deterg. 2011;14:203–
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4
CONCLUSIONS
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In the present investigation, an attempt has been made to
investigate the kinetic efficiency of pyridinium-based func-
tionalized surfactants toward the micellar hydrolysis of phos-
phate esters. Considerable enhancement in the rate of hydrol-
ysis reaction was observed on increment of the alkyl chain
−
length of functionalized surfactants. 4-C14PyOx /CPB was
found to be the most reactive system among all the inves-
tigated oximes for the cleavage of phosphate esters. These
systems are very efficient in promoting phosphate esterolysis.
Results of the present investigation provide useful informa-
tion for development of an effective system for degradation of
toxic pesticides and nerve agents.
9. (a) Kotoucova H, Cibulka R, Hampl F, Liska F. Amphiphilic qua-
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ternary pyridinium ketoximes as functional hydrolytic micellar cat-
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ACKNOWLEDGMENTS
The authors are thankful to Chhattisgarh Council of Science
and Technology (CCOST) (grant no. 1104/CCOST/MRP/15,
dated April 9, 2015), University Grants Commission,
New Delhi, India, research award (2016–2018) (grant
no. 30-1/2015 (SA-II), DST-FIST (grant no. SR/FST/CSI-
259/2014(C)), and UGC-SAP (grant no. F-540/7/DRS-
II/2016 (SAP-I)) for providing financial assistance. We are
also thankful to Head, School of Studies in Chemistry, Pt.
Ravishankar Shukla University, Raipur, India, for providing
lab facilities.
10. Scrimin P, Tecilla P, Tonellato U, Bunton CA. Nucleophilic cataly-
sis of hydrolyses of phosphate and carboxylate esters by metallomi-
celles. Colloids Surf A. 1998;144:71–79.
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vitro reactivation kinetics of paraoxon- and DFP-inhibited electric
eel AChE using mono- and bis-pyridinium oximes. Arch Toxicol.
2014;88:381–390.
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lated or phosphorylated monoperoxyphthalates in the catalytic
esterolytic reactions in cationic surfactant aggregates. J Org Chem.
1997;62:2198–2204.
ORCID
Manmohan L. Satnami
http://orcid.org/0000-0002-8692-7506
13. Mancin F, Scrimin P, Tecilla P, Tonellato U. Amphiphilic metal-
loaggregates: catalysis, transport, and sensing. Coord Chem Rev.
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SUPPORTING INFORMATION
Additional supporting information may be found online in the
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How to cite this article: Kandpal N, Dewangan HK,
Nagwanshi R, Ghosh KK, Satnami ML. Micellarac-
celerated hydrolysis of organophosphate and thiophos-
phates by pyridine oximate. Int J Chem Kinet. 2018;1–
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of a potent reactivator of tabun-inhibited acetylcholinesteras-