Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations
The complexation by β-cyclodextrin (β-CD) of three organophosphorus pesticides, fenitrothion, parathion and methylparathion, and of their carboxylic ester analogues was analyzed using PM3 and molecular mechanics methods. The objective was to elucidate structural features and energy changes that acco...
Guardado en:
| Autores principales: | , , , , , |
|---|---|
| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
2009
|
| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/147358 |
| Aporte de: |
| id |
I19-R120-10915-147358 |
|---|---|
| record_format |
dspace |
| institution |
Universidad Nacional de La Plata |
| institution_str |
I-19 |
| repository_str |
R-120 |
| collection |
SEDICI (UNLP) |
| language |
Inglés |
| topic |
Química supramolecular complexes E-cyclodextrin inclusion compounds semiempirical calculations pesticides |
| spellingShingle |
Química supramolecular complexes E-cyclodextrin inclusion compounds semiempirical calculations pesticides Coscarello, Ethel Noemí Barbiric, Dora Ana Josefina Castro, Eduardo Alberto Vico, Raquel Bujánm, E. I. Rossi, R. H. de Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| topic_facet |
Química supramolecular complexes E-cyclodextrin inclusion compounds semiempirical calculations pesticides |
| description |
The complexation by β-cyclodextrin (β-CD) of three organophosphorus pesticides, fenitrothion, parathion and methylparathion, and of their carboxylic ester analogues was analyzed using PM3 and molecular mechanics methods. The objective was to elucidate structural features and energy changes that accompany the complexation and could possibly affect the hydrolysis process, which is catalyzed by β-CD in the case of carboxylic esters but inhibited for the pesticides, in alkaline medium. The complexation of fenitrothion was further explored, since experiments proved its hydrolysis is relatively less inhibited and progresses mainly through a different pathway than that usually accepted. The results of this study show that complex structures involving esters enable effective interactions between the guest carbonyl and the rim of the host; methylparathion and parathion, however, appear to be deeply included in the cavity of β-CD. Therefore the conditions for a nucleophilic attack by the β-CD are favorable for the carboxylic esters but not for the two pesticides. Different complex geometries resulted for fenitrothion depending on its mode of inclusion in the cavity, none apparently being prone to an attack by the β-CD, but favoring instead the approach of an external OH− group, in agreement with the experiment. |
| format |
Articulo Articulo |
| author |
Coscarello, Ethel Noemí Barbiric, Dora Ana Josefina Castro, Eduardo Alberto Vico, Raquel Bujánm, E. I. Rossi, R. H. de |
| author_facet |
Coscarello, Ethel Noemí Barbiric, Dora Ana Josefina Castro, Eduardo Alberto Vico, Raquel Bujánm, E. I. Rossi, R. H. de |
| author_sort |
Coscarello, Ethel Noemí |
| title |
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| title_short |
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| title_full |
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| title_fullStr |
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| title_full_unstemmed |
Comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : Theoretical semiempirical calculations |
| title_sort |
comparative analysis of complexation of pesticides (fenitrothion, methylparathion, parathion) and their carboxylic ester analogues by β-cyclodextrin : theoretical semiempirical calculations |
| publishDate |
2009 |
| url |
http://sedici.unlp.edu.ar/handle/10915/147358 |
| work_keys_str_mv |
AT coscarelloethelnoemi comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations AT barbiricdoraanajosefina comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations AT castroeduardoalberto comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations AT vicoraquel comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations AT bujanmei comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations AT rossirhde comparativeanalysisofcomplexationofpesticidesfenitrothionmethylparathionparathionandtheircarboxylicesteranaloguesbybcyclodextrintheoreticalsemiempiricalcalculations |
| bdutipo_str |
Repositorios |
| _version_ |
1764820461256966145 |