Enantioselective Fate of Chiral Chlorinated Hydrocarbons and Their Metabolites in Environmental Samples

Abstract

Gas chromatographic enantioseparation of chiral organochlorines (α-HCH, cis-and trans-chlordane, heptachlor, heptachlor epoxide, oxychlordane, o, p -DDT, compounds of technical toxaphene, stable atropisomeric PCBs and methylsulfonyl-PCBs) has been achieved during the last decade. For this purpose chiral stationary phases based on cyclodextrin derivatives have been applied in combination with GC/ECD, GC/MS, MDGC, and MS/MS. With these techniques methods have been developed which have been used to study the enantioselective fate of the chiral organochlorines. Changes in the enantioratios and conclusions drawn are reviewed. phenomenon of plane-polarized light (Malus, 1809) and optical rotation (Biot,113

Enantioselective Oxidative Damage of Chiral Pesticide Dichlorprop to Maize

“…Chiral enantiomers have identical physical and chemical properties in achiral environments (e.g., airÀwater exchange, sorption, and abiotic transformation), but they show different activities in biological systems because individual enantiomers can interact enantioselectively with enzymes and biological receptors in organisms. 1,2 Enantioselectivity of chiral pesticides in the environment, such as enantioselective degradation and toxicity, is receiving increasing attention. 3,4 Despite their application to soil and direct exposure to plants, enantioselective toxicity of chiral pesticides to plants has not received enough attention.…”

Enantioselectivity in environmental safety of current chiral insecticides

“…However, enantiomers are known to selectively interact with biological systems that are usually enantioselective and may behave as drastically different compounds. The role of enantioselectivity in environmental safety is poorly understood for pesticides, and the knowledge gap is reflected in that the great majority of chiral pesticides are used and regulated as if they were achiral, that is, single compounds.Studies on chiral pesticides started to appear in the early 1990s (4,(5)(6)(7)(8)(9)(10)(11)(12). Studies so far show that microbial degradation of chiral pesticides is commonly enantioselective.…”

“…Studies on chiral pesticides started to appear in the early 1990s (4,(5)(6)(7)(8)(9)(10)(11)(12). Studies so far show that microbial degradation of chiral pesticides is commonly enantioselective.…”

Chiral pesticides

“…43) Scientists reported an efficient practical and systematic optical resolution method for gem-dihalocyclopropanecarboxylic acid (C) using chiral 1,1Ј-binaphthol monomethyl ether (B) as the key auxiliary to obtain (G) and (H) (Scheme 2). 41) Moreover, this method was applied to the synthesis of chiral pesticides [carpropamid (23), fencyclate (24) and pyrethroid with three asymmetric centers (25) 41) ] (Fig. 6).…”

“…Studies on chiral pesticides started to appear in the early 1990s. [19][20][21][22][23][24][25][26][27][28] Companies have been deeply interested in selling synthetic chiral pesticides as single enantiomers in the past decade. The key reasons why single isomers are less common than they could be are probably limited access to chiral raw materials and economic synthetic routes.…”