Structure–efficiency relationships of cyclodextrin scavengers in the hydrolytic degradation of organophosphorus compounds

• Sophie Letort,
• Michaël Bosco,
• Benedetta Cornelio,
• Frédérique Brégier,
• Sébastien Daulon,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2017, 13, 417–427, doi:10.3762/bjoc.13.45

• fenitrothion (Figure 4) were also investigated. Finally, compounds 1–4 were tested for their detoxification ability against the nerve agent soman. Results and Discussion Synthesis The regioselective disubstitution of diol 6 (Scheme 1) was the key step to access derivatives 2 and 3. The synthetic methodology

• promising disubstituted cyclodextrin for the degradation of methyl paraoxon. Therefore, this compound was subsequently used in the hydrolysis of other pesticides (Figure 9). Compound 2 was found to hydrolyze the organophosphorus compounds in the following order: fenitrothion < methyl parathion < methyl

• -iodosobenzoic acid (IBA), imidazole and TRIMEB were 0.5 mM. Influence of the pesticide structure on the hydrolytic efficiency of compound 2 (0.25 mM). Kinetic assays were carried out with methyl paraoxon, methyl parathion or fenitrothion (0.5 mM). Influence of TRIMEB, IBA and imidazole on the hydrolysis of

Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

• Sophie Letort,
• Sébastien Balieu,
• William Erb,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2016, 12, 204–228, doi:10.3762/bjoc.12.23

• ions in the solvent. Acting as the active site, the substitution of secondary hydroxy groups might impact the hydrolysis rate. This was investigated comparing the effect of β-CD, DIMEB and TRIMEB on the alkaline hydrolysis of parathion, methyl parathion, and fenitrothion [53][54]. In all host–guest

• systems, the rate of alkaline hydrolysis is reduced with the the inclusion of the organophosphorothioate pesticides into the CDs (kc/kun < 1, Table 3). However it appears clearly that the three studied CDs do not share the same pesticide hydrolysis inhibition level as in all cases, fenitrothion is

• hydrolyzed faster than parathion and methyl parathion. Indeed the two latter can form deeply included complexes (high αin parameter) compared to fenitrothion which is therefore less shielded from hydroxide ions, leading to the highest hydrolysis rate observed in this series (Table 3) [42]. The origin of this

Inclusion of the insecticide fenitrothion in dimethylated-β-cyclodextrin: unusual guest disorder in the solid state and efficient retardation of the hydrolysis rate of the complexed guest in alkaline solution

• Dyanne L. Cruickshank,
• Natalia M. Rougier,
• Raquel V. Vico,
• Susan A. Bourne,
• Elba I. Buján,
• Mino R. Caira and
• Rita H. de Rossi

Beilstein J. Org. Chem. 2013, 9, 106–117, doi:10.3762/bjoc.9.14

• Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina 10.3762/bjoc.9.14 Abstract An anhydrous 1:1 crystalline inclusion complex between the organophosphorus insecticide fenitrothion [O,O-dimethyl O-(3-methyl-4-nitrophenyl

• (distinguishable as rotamers with respect to the P–OAr bond) while in the other, three distinct guest components with site-occupancies 0.44, 0.29 and 0.27 appear, the last having a reversed orientation relative to all the other components. Kinetic studies of the alkaline hydrolysis of fenitrothion in the presence

• of DIMEB showed a remarkable reduction of 84% in the rate of this reaction relative to that for the free substrate, a value exceeding those previously attained with the native hosts, β- and γ-cyclodextrin, and fully methylated β-cyclodextrin. Keywords: crystal structure; cyclodextrin; fenitrothion