Pyrethroid tshuaj tua kab muaj zog chiral yam ntxwv thiab feem ntau muaj ntau yam chiral enantiomers.Txawm hais tias cov enantiomers muaj tib lub cev thiab cov khoom siv tshuaj lom neeg, lawv nthuav tawm tag nrho cov tshuaj tua kab sib txawv thiab cov khoom lom hauv vivo.Toxicity thiab ib puag ncig residue qib.Xws li Cypermethrin, Beta-Cypermethrin, Alpha-cypermethrin;beta-cypermethrin, cyhalothrin;Beta Cyfluthrin, cyfluthrin, thiab lwm yam.

Cypermethrin
Cypermethrin yog cov tshuaj tua kab pyrethroid feem ntau siv dav.Nws cov qauv molecular muaj 3 chiral chaw thiab 8 enantiomers.Cov enantiomers sib txawv qhia qhov sib txawv tseem ceeb hauv kev ua haujlwm lom neeg thiab tshuaj lom.
Lub 8 optical isomers ntawm Cypermethrin tsim 4 khub ntawm racemates.Muaj qhov sib txawv pom tseeb hauv kev tua cov nyhuv thiab photolysis ceev ntawm cov isomers sib txawv ntawm Cypermethrin ntawm kab.Lawv cov tshuaj tua kab los ntawm qhov muaj zog mus rau qhov tsis muaj zog yog cis, trans Formula, cis-trans cypermethrin.
Ntawm yim isomers ntawm Cypermethrin, ob ntawm plaub trans isomers thiab plaub cis isomers muaj txiaj ntsig zoo.
Txawm li cas los xij, yog tias ib qho kev ua tau zoo ntawm isomer ntawm Cypermethrin siv los ua tshuaj tua kab, tsis tsuas yog nws cov tshuaj tua kab tuaj yeem txhim kho tau zoo, tab sis kuj muaj cov tshuaj toxicity rau cov kab mob uas tsis yog hom phiaj thiab cov kev tsis zoo ntawm ib puag ncig tuaj yeem txo.Yog li ntawd, Beta-Cypermethrin thiab Alpha-cypermethrin tau los ua:

Alpha-cypermethrin
Alpha-cypermethrin cais ob hom kev ua haujlwm qis lossis tsis muaj txiaj ntsig los ntawm kev sib xyaw uas muaj plaub cis-isomers, thiab tau txais 1: 1 sib tov uas tsuas muaj ob qhov ua tau zoo cis-isomers.
Alpha-cypermethrin muaj ob zaug cov tshuaj tua kab ntawm Cypermethrin.

Beta-Cypermethrin
Beta-Cypermethrin, English lub npe: Beta-Cypermethrin
Beta-Cypermethrin tseem hu ua high-efficiency cis-trans cypermethrin.Nws hloov cov ntaub ntawv tsis zoo ntawm cov txheej txheem cypermethrin uas muaj 8 isomers rau hauv daim ntawv ua haujlwm siab los ntawm catalytic isomerization, yog li tau txais kev ua haujlwm siab cis isomers thiab high-efficiency cypermethrin.Kev sib xyaw ntawm ob khub ntawm racemates ntawm trans isomers muaj 4 isomers, thiab qhov piv ntawm cis thiab trans yog kwv yees li 40:60 lossis 2: 3.
Beta- Cypermethrin muaj tib yam tshuaj tua kab zoo li Cypermethrin, tab sis nws cov tshuaj tua kab mob yog li 1 npaug siab dua li ntawm Cypermethrin.
Beta-Cypermethrin tsis tshua muaj tshuaj lom rau tib neeg thiab tsiaj txhu, thiab nws cov tshuaj lom rau cov kab tsuag huv si sib npaug los yog ntau dua li Alpha-cypermethrin, yog li nws muaj qee yam zoo hauv kev tiv thaiv thiab tswj cov kab tsuag huv.

Cov ntsiab lus
Txij li thaum kev ua haujlwm lom neeg ntawm daim ntawv cis-high-efficiency feem ntau siab dua li ntawm daim ntawv trans-high-efficiency, qhov kev txiav txim ntawm cov tshuaj tua kab ntawm peb cov kwv tij ntawm cypermethrin yuav tsum yog: Alpha-cypermethrin≥Beta-Cypermethrin> Cypermethrin.
Txawm li cas los xij, Beta-Cypermethrin muaj kev tiv thaiv kab mob zoo dua li lwm yam khoom siv.