Pheromones female gypsy moth

Functional group transformations of epoxides rank among the fundamental reactions of organic chemistry and epoxides are commonplace natural products The female gypsy moth for example attracts the male by emittmg an epoxide known as disparlure On detechng the presence of this pheromone the male follows the scent to its ongm and mates with the female... 

FIGURE 1.4 Active space for different wind speeds. A single female gypsy moth at the tree on the left emits sex attractant. The space where the concentration of pheromone is above threshold (for a searching male) is defined by the dimensions x, y, and z. The active space shrinks with increasing wind velocity. (From Wilson, 1970.)... 

Female gypsy moths emit the pheromone disparlure (top) to entice male gypsy moths (bottom left) into mating. The males ate so sensitive to this compound that they can detect one molecule in 1017 molecules of air. This astounding sensitivity enables them to respond to a female who may be more than 1 kilometer away. However, they can also be tricked into responding to insecticide traps laced with synthetic disparlure (bottom right). 

Jurenka R. A. and Subchev M. (2000) Identification of cuticular hydrocarbons and alkene precursor to the pheromone in hemolymph of the female gypsy moth, Lymantria dispar. Arch. Insect Biochem. Physiol. 43, 108-115. 

Hollander A. L. and Yin C.-M. (1985) Lack of humoral control in calling and pheromone release by brain, corpora cardiaca, corpora allata and ovaries of the female gypsy moth, Lymantria dispar (L.). J. Insect Physiol. 31, 159-163. 

The occurrence of hydrocarbons (usually mono- and di-alkenes) with an epoxide function group have been reported usually as sex attractants. The sex attractant of the female gypsy moth, Lymantria dispar, was identified as the C18 2-methyl alkane derivative cis-7,S-epoxy-2-methyloctadecane (Bierl et al 1972). For the housefly, M. domestica, a major sex pheromone component is the C23 -alkane epoxide d.v-9,1O-cpoxytricosane (Uebel et al 1978) with a lesser quantity of 9,10-epoxyheptacosane (Mpuru et al., 2001). 

Disparlure, the sex pheromone of the female gypsy moth, has been used to control the spread of the gypsy moth caterpillar, a pest that has periodically devastated forests in the northeastern United States by defoliating many shade and fruit-bearing trees.The active pheromone is placed in a trap containing a poison or sticky substance, and the male moth is lured to the trap by the pheromone. Such a species-specific method presents a new way of controlling an insect population that avoids the widespread use of harmful, nonspecific pesticides. Disparlure is synthesized by oxidation of an alkene using chemistry presented in Chapter 12. 

Disparlure, the sex pheromone of the female gypsy moth and the epoxide that opened Chapter 12, is synthesized by a stepwise reaction sequence that uses an epoxidation reaction as the final step. 

Put on safety glasses. Pour a little anunonia in a bowl, place it in one comer of the room, and then walk to the far comer of the room. If you wait a moment or two, the smell of ammonia should reach you because the gas-phase ammonia molecules are very lightweight and diffuse quickly. Insects rely heavily on diffusion. Pheromones, or chemical substances released as odors, are used as a primary method of communication among our more diminutive brethren. The male gypsy moth can detect a burst of a few hundred molecules of a sex attractant from a female gypsy moth located as far as three miles away. Love is a wonderful thing. 

Disparlure, [cw-(7i ,85)-( + )-7,8-epoxy-2-methyloctadecane] (490) is the sex pheromone of the female gypsy moth Prothetria dispar L. Its stereoselective synthesis utilizes the threo configuration present in diethyl (2i ,3i )-( + )-tartate (lb). Conversion of 577, prepared... 

This methodology [94TL3601] was used to construct the optically active erythro-diol 8, which was then stereospecifically converted to (+)- disparlure (9), the sex attractant pheromone of the female gypsy moth. This transformation represents a formal asymmetric epoxidation across a nonfunctionalized olefin, not a direct option with traditional Sharpless asymmetric epoxidation technology. This clever variation using initial Sharpless dihydroxylation (applicable to nonfunctionalized olefins) and subsequent epoxide formation is starting to be recognized as a useful indirect method for asymmetric epoxidation. 

Chanical signaling often involves the use of pheromones, volatile chemicals released into the environment, usually as sex attractants. They are extremely specific and affect only others of the same species. The concentrations of pheromones that elicit a response are extremely small. Glypure, the gypsy moth sex attractant pheromone, has a male threshold value of about 1.25 x lO kg/m in the air (Johnson, 1999). Female gypsy moths release the glypure into the air and males follow the scent to the female. Artificially synthesized insect pheromones are used in two ways (1) to trap insect pests, and (2) to overwhelm and confuse insects to disrupt mating. 

Disparlure, the sex attractant pheromone of the female gypsy moth, has the following general structure. Are geometric isomers possible for this molecule ... 

R,8S)-(+)-Disparlure (12) is the female sex pheromone of the gypsy moth (Lymantria dispar). Advent of Sharpless asymmetric dihydroxylation (AD) allowed several new syntheses of 12 possible. Sharpless synthesized 12 as shown in Scheme 17 [27]. Scheme 18 summarizes Ko s synthesis of 12 employing AD-mix-a [28]. He extended the carbon chain of A by Payne rearrangement followed by alkylation of an alkynide anion with the resulting epoxide to give B. Keinan developed another AD-based synthesis of 12 as shown in Scheme 19 [29]. Mit-sunobu inversion of A to give B was the key step, and the diol C could be purified by recrystallization. 

Pheromone-mediated diel activity rhythms of male Asian gypsy moth (Lepidoptera Lymantriidae) in relation to female eclosion and temperature. Annals of the Entomological Society of America 89 745-753. 

Giebultowicz J. M., Raina A. K., Uebel E. C. and Ridgway R. L. (1991) Two-step regulation of sex-pheromone decline in mated gypsy moth females. A rch. Insect Biochem. Physiol. 16, 95-105. 

Females of the lymantriid, Porthetria dispar, the gypsy moth, liberate cls-7,8-epoxy-2-methyloctadecane (disparlure) as a sex pheromone (78). The probable precursor of the epoxide, (Z)-2-methyl-7-octadecene, is present in the gland in large quantities, and it has been demonstrated that the olefin is epoxidized in vivo (79). Disparlure is rapidly adsorbed on the male antennae and quickly converted to two more polar metabolites (80), probably as a consequence of hydrolysis of the epoxide group. 

The female pheromone of the gypsy moth was claimed to be gyptol (A, Table 7.2), while the true pheromone was disparlure (85). Although the female pheromone of the American cockroach was claimed to be a cyclopropane compound B, the genuine and major pheromone was periplanone-B. The female pheromone of the pink bollworm moth was proposed as propylure (C), while the genuine pheromone was gossyplure as a mixture of two isomers. In these three cases, the synthetic compounds with the false... 

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