Pyrethrum Cinerins

Jasmolin II in pure form was nearly equal to cinerin II in toxicity to houseflies but much less when synergized. The synergistic factor of the synergized compounds is pyrethrum extract 9.6 jasmolin II, 7.0 cinerin II, 12.0. 

Sawicki et al. (33) prepared by reconstitution pure samples of pyrethrins I and II and cinerins I and II and compared the toxicity of these esters with the regular pyrethrum extract on houseflies 5 to 6 days old. 

Figure 1 presents the gas chromatographic responses obtained from a pyrethrum concentrate. Peak I has been identified as cinerin I, peak II as a cinerin-type compound, peak III as pyrethrin I, peak... 

Synonyms Pyrethrin I or II Cinerin I or II Jasmolin I or II. Note Pyrethrum flowers yield pyrethrum extract, of which the insecticidal constituents are collectively the pyrethrins or the natural pyrethrins ... 

Pyrethrins and pyrethroids are probably the best known and safest classes of natural or synthetic insecticides, widely used in domestic and agricultural applications (1-7). Pyrethrins are natural insecticides derived from the Chrysanthemum cineraria flowers the plant extract, called pyrethrum, is a mixture of six isomers (pyrethrin I and II, cinerin I and II, jasmolin I and II) which was first used in China in the century AD, during the Chou Dinasty. The world pyrethrum market is worth half a billion US dollars [main producers are East Africa highlands (Kenia, Tanzania and Rwanda) and Australia] however, its availability is subject to cyclical trends, due to rains and relations with farmers, who face high harvest costs also due to the fact that the flowers have to be... 

Pyrethrum (Chrysanthemum) dnerarifolium (Asteraceae) namely cinerin I (CMC cineralone ester), cinerin II (CDC monomethyl ester cinerolone ester), pyrethrin I (CMC pyrethrolone ester) and pyrethrin II (CDC monomethyl ester pyrethrolone ester). The chrysanthemum carboxylic acids are cyclopropane-based monoterpenes and cineralone and pyrethrolone are cyclopentanone monoterpene alcohols. The pyrethrins (and their insecticidal synthetic derivatives) are toxic to insects through keeping cell membrane voltage-gated Na+ channels open and thus impairing neurotransmission. 

Pyrethroids consist of pyrethrum and its synthetic pyrethrum analogs called synthetic pyrethroids. Pyrethrum is a solvent extract of dried flowers of Chrysanthemum cinerariaefo-lium. The active ingredients of pyrethrum are called pyrethrins. Pyrethrins consist of four esters, namely, pyrethrins I and II and cinerins I and II, which comprise the combination of two different alcohols (pyrethrolone and cinerolone) and two different acids (chrysan-themic acid and pyrethric acid), as follows ... 

Pyrethrum is an extract of dried chrysanthemum flowers. The extract contains about 50% active insecticidal ingredients known as pyrethrins. The ke-toalcoholic esters of chrysanthemic and pyrethroic acids are known as pyrethrins, cinerins, and jasmolins. These strongly lipophilic esters rapidly penetrate many insects and paralyze their nervous systems. Both crade pyrethrum... 

Properties Viscous liquid. Bp 170° (0.1 mm) decomposes. A natural insecticide obtained by extraction of chrysanthemum flowers native to Kenya, Ecuador, and Japan. The solvent used is a hydrocarbon of the kerosene type. Pyrethrum is also made synthetically. Not compatible with alkaline material. The chief constituents are pyrethrins I and II and cinerins I and II. These compounds are nonvolatile and very slightly soluble in water. 

CAS registry number of all the pyrethrum constituents is same. However, chemical formulae are some what different. For instance, pyrethrin I is C21H28O3, pyrethrim II is C22H28O5, cinerine I is C20H28O3, cinerine II is C21H28O5, etc. 

Pyrethroids form a uniform group of pesticides, some of which are naturally occurring, and many are synthetic analogues of these. The natural pyrethroids are obtained from pyrethrum, a substance that is extracted from the flowers of certain species of chrysanthemum. Pyrethrum is made up of six naturally occurring esters, two of which are sometimes referred to as pyre-thrins, the other being known as cinerins and jasmolins. 

Cbrysanthemic Acid. 2y2-Dimethyl-3-<2-methyl-I -property )cyclopropa neca rboxyl ic acid ch rysan them ummo -nocarboxylic acid chrysanthemumic acid. C,0H,6O2 mol wt 168.23. C 71.39%, H 9.59%, O 19.02%. Occurs as esters in pyrethrum flowers, see Pyrethrin I and Cinerin I, also Alle-... 

OTHER COMMENTS pyrethrum is a variable mixture of Cinerin, Jasmolin, and Pyre-thrin application as an insecticide on agricultural crops, cattle, poultry, and food cartons used in the formulation of scabicides and parasiticides for medical and veterinary use. 

Chrysanthemol from the leaves of Artemisia ludiviciana (Asteraceae) belongs to the cyclopropane monoterpenes Cinerins, jasmolins and pyrethrins (all including derivatives 1 and 11) are esters of /rara-chrysanthemic and pyrethric acid with terpenoid hydroxypentenones such as cinerolone, jasmolone and pyrethrolone. These are the active insecticidal constituents of pyrethrum recovered from dried flowers of several Chrysanthemum species (e.g. Chrysanthemum cinerariaefolium, Asteraceae). Some synthetic esters of chrysanthemic acid are also applied as insecticides. 

Ecuador into the U.S. The active principals are pyrethrins I and II, cinerins I and II, and jasmolin I and II, collectively known as pyrethrins. Pyrethrins are used extensively in stock sprays, pet sprays, household sprays, aerosols, and food protection in warehouses. Pyrethrins are stable for long periods in water-based aerosols, in which modern emulsifiers are used. Dermatitis from natural pyrethrins usually occurs on parts of the body exposed to the spray. The substance is a moderately potent allergic sensitizer. Crossreactions occur among pyrethrum, chrysanthemum, shasta daisy, and ragweed oleo resin [31, 32]. Asthma and urticaria have also been reported as reactions to natural pyrethrin [33, 34]. In 1972, Mitchell et al. found that a sesquiterpene lactone, pyrethrosin, was the chief allergen in pyrethrin [35]. Contact dermatitis due to pyrethrum is usually mild, but bullous reactions have been reported [36]. In Denmark, positive patch-test reactions to pyrethrum were obtained in 1-2% of dermatitis patients [37]. 

Fig. 183. Thin-layer chromatograms of ordinary commercially available pyrethrum extracts of different ages (a, 6, c), photographed in short wave UV light [92]. A on silica gel HF254 under normal conditions B in the BN-chamber using continuous development with solvent I (concluded when the butter yellow attained the evaporation zone) C continuous development with solvent II (concluded when the indophenol reached the evaporation zone) Ja jasmoUn Ci cinerin Pypyrethrin ...

Essig, K. Zhao, Z. Method development and validation of a high-performance liquid chromatographic method for pyrethrum extract, J.Chromatogr.Sci., 2001, 39, 473-480. [pyrethrins cinerin jasmolin ... 

Pyrethrum flower consists of the dried flowerhead of Chrysanthemum cinerar ice folium Vis. and it owes its insecticidal properties to two types of ketoesters. One group consists of pyrethrin I and cinerin I, both of which have chrysanthemum monocarboxylic acid (chrysanthemic acid) as their acid component. The assay given below for pyrethrin I, which is based on the determination of total chrysanthemic acid, will therefore include cinerin I. The second group of esters consists of pyrethrin II and cinerin II, both of which have the monomethyl ester of chrysanthemum dicarboxylic acid (pyrethric acid) as their acid component since the assay given below for pyrethrin II is based on the determination of total pyrethric acid it will therefore include cinerin II. The keto-alcohol component of the pyrethrins is pyrethrolone and that of the cinerins is cinerolone. 

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