Explanation of Where and How Enantioselective Binding Takes Place on Permethylated β-Cyclodextrin, a Chiral Stationary Phase Used in Gas Chromatography

Lipkowitz, Kenny B.; Pearl, Greg M.; Coner, and Bob; Peterson, Michael A.

doi:10.1021/ja963076x

Cited by 89 publications

(54 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The chiral discrimination mechanism on CSPs has been examined using spectroscopic 13,14 and computer-aided methods. 15,16 Computational studies of the chiral discrimination mechanism on phenylcarbamate derived cellulose have been reported and the results of computational calculations show good agreement with chromatographic results. 17 The insecticidal activities of pyrethroids are closely PYRETHROIC ACID ESTERS related to their absolute configuration.…”

mentioning

confidence: 71%

Enantiomeric discrimination of pyrethroic acid esters on polysaccharide derived chiral stationary phases

Kim¹,

Lee²,

Kim³

et al. 2003

Chirality

View full text Add to dashboard Cite

Enantiomeric separation of pyrethroic acid methyl and ethyl esters was examined on cellulose-based chiral stationary phases (CSPs): chiralcel OD (cellulose tris(3,5-dimethylphenyl carbamate)) and chiralcel OF (cellulose tris(4-chlorophenyl carbamate)). The good resolution of pyrethroic acid esters was achieved on chiralcel OD and OF. Separation factors ranged from 1.19-5.12 for Chiralcel OD and 1.00-1.59 for chiralcel OF. Hexane/2-propanol (100:0.15, v/v %) was used as the eluent. The resolution capability of CSPs was greater chiralcel OD than chiralcel OF in the case of the pyrethroic acid esters. The flow rate was 0.8 ml/min and detection was set at 230 nm. The results of the chromatographic data and molecular mechanics suggest that steric effect was a major factor in the enantioseparation. Furthermore, the hydrogen bond between analytes and CSP played an important role in the chiral recognition. Chirality 15: 276-283, 2003. © 2003 KEY WORDS: chiral discrimination; pyrethroic acid ester; HPLC; enantioseparation; molecular mechanics; cellulose tris(3,5-dimethylphenyl carbamate); chiralcel OD; cellulose tris(4-chlorophenyl carbamate); chiralcel OF The natural insecticidal compound pyrethrin was available in the form of dried flowers of Chrysanthemum roseum as early as the beginning of the 19th century. The active insecticidal component of pyrethrum extract is a mixture of six related compounds, known as pyrethrins, of which the most potent are pyrethrins I and II. Pyrethroids are important in agriculture and household usage because of their high insecticidal activity and very low mammalian toxicity. Pyrethroid insecticides with greater stability were sought to replace the increasing insect resistance to organophosphates.1 Most pyrethroids contain a mixture of isomers, both inactive and active isomers. Many are now being sold as the resolved form of the original product, containing only the active isomers or a higher ratio of active isomers. Therefore, enantiomer separation of pyrethroids and their intermediates is a very important task. As shown in Figure 1, pyrethroic acid esters show that two asymmetric carbon atoms give rise to four isomers, two pairs of which have geometric isomer cis-and trans-configuration with respect to the plane of the cyclopropane ring. Micellar electrokinetic capillary chromatographic (MECC) methods using types of cyclodextrin and their derivatives in phosphate buffer containing several surfactants as chiral selector have been reported to separate the enantiomers of cypermethrin, alphamethrin, permethrin, and fenpropathrin. 2 (1R,3R)-trans-Chrysanthemic acid and its amide derived chiral stationary phases (CSPs) have been employed for enantiomer separation of trans-chrysanthemic acid 3,5-dinitroanilide.3 Gas chromatographic separation of chrysanthemic acid ester enantiomers has been reported. In that article, a novel amide phase derived from (1R,3R)-trans-chrysanthemic acid with (S)-mandelic acid (R)-1-(␣-naphthyl)-ethyl amide shown good stereoselectivity for chrysanthemic aci...

show abstract

mentioning

confidence: 71%

Enantiomeric discrimination of pyrethroic acid esters on polysaccharide derived chiral stationary phases

Kim¹,

Lee²,

Kim³

et al. 2003

Chirality

View full text Add to dashboard Cite

show abstract

“…To determine the preferential binding site of the guest molecule, the number densities of presence in a volume element are calculated. We define a grid in which the distance between two consecutive points is 0.5 Å and the number of guest positions in each volume element is the resulting number density for each trajectory and for the guest [10][11][12]. The position probability density is calculated by dividing the number density in a volume element by the total number of centre of mass positions of the guest.…”

Section: Expression Of the Interaction Potentialmentioning

confidence: 99%

Capacity of small molecules to form β-cyclodextrin inclusion complexes

Alvira

2009

Supramolecular Chemistry

View full text Add to dashboard Cite

“…15 together with Fig. 8 (CSD code, DOCYID, 16) the example of g-CD; the guest, 12-crown-4-ether), r increases more than in b-CD. The guest molecule has large r width but occupies a narrow Z-value range compared with the guests mentioned in the above two examples, and thus the guest is located in the large Z-value of the CD region and Vol.…”

mentioning

confidence: 94%

“…For permethylated b-CD, Lipkowitz et al found the most enantio-diŠerentiating region of CD for chiral recognition and made contour plots. 16) Their contour plot method is also based on the exhibition of the actual 3-dimensional structure by the method of perspective drawing.…”

Section: Introductionmentioning

confidence: 99%

Mapping of the Cyclodextrin Cavity Using the Cylindrical Coordinate System

Akimoto¹

2005

YAKUGAKU ZASSHI

View full text Add to dashboard Cite

This paper describes the mapping of the inner cavity of cyclodextrin and the guest molecule using the cylindrical coordinate system. Each cavity structure of a-, b-, and g-cyclodextrin was examined using the coordinate system, in which, the Z-axis passes through the molecular axis; a normal of the plane that consists of 6, 7, or 8 C 1 atoms of glucose units was obtained using the least-squares methods and that passes through the center of C 1 atoms. The radius r is the distance from the Z-axis to the solvent-accessible surface of a cavity. The q-axis is deˆned such that the nearest C 1 atom of the glucose unit to the Z-axis is its origin. The atomic character of the inner surface of the cavity was also obtained and plotted in the same coordinates. The guest molecule was plotted with the same coordinate system as cyclodextrin to see atoms with large r distance of the guest molecule on the solvent-accessible surface map of cyclodextrin. It was conrmed from the map that cyclodextrin molecules have an ellipsoidal shape, have pseudo-n-hold symmetry (n＝6 to a, 7 to b, and 8 to g) in relation to their molecular axis, and guest molecules are located in relatively hydrophobic regions. It was also conˆrmed that the maps of this system give insights into the complementary characters of structures between the host and the guest by plotting the guest molecule in the same coordinate system.

show abstract

Explanation of Where and How Enantioselective Binding Takes Place on Permethylated β-Cyclodextrin, a Chiral Stationary Phase Used in Gas Chromatography

Cited by 89 publications

References 78 publications

Enantiomeric discrimination of pyrethroic acid esters on polysaccharide derived chiral stationary phases

Enantiomeric discrimination of pyrethroic acid esters on polysaccharide derived chiral stationary phases

Capacity of small molecules to form β-cyclodextrin inclusion complexes

Mapping of the Cyclodextrin Cavity Using the Cylindrical Coordinate System

Contact Info

Product

Resources

About