Juvenil hormone

Farnesol derivatives also have juvenile hormone activity. 

Insect juvenile hormone Insect repellents Insect resistance Insects... 

L. 1. Gilbert, ed.. The Juvenile Hormones, Plenum Press, New York, 1976. 

Cinnamyl—sesamol ethers, eg (35), are useful as insect chemosterilants (111). 3,4-Methylenedioxyphenyl-3-halo-2-propynyl ethers (36, X = halogen) are synergists for carbamate insecticides (112). HaloaLkyl or haloalkenyl ethers, eg (37), show acaricidal and insect juvenile hormone activity (113). The first total synthesis of gibbereUic acid was from 2-methoxy-6-aLkoxyethyl-l,4-benzoquinone, a derivative of hydroxyhydroquinone (114). 

Thiiranes (77) show some juvenile hormone activity, but the epoxide is often more active. Thiophosphates of 2-mercaptomethylthiirane are strong contact insecticides 2-chloromethylthiirane and4-vinyl- 1,2-epithiocyclohexane are nematocides. Severalthiirane 1 -oxides are reported to be insecticides, molluscicides and herbicides (68USP3413306). 1,2-Epithio-1,2,3,4-tetrahydronaphthalene is a mild herbicide. 

Insects, crustaceans, platehelminthes, nematodes and annelids use homoses-quiterpenoid epoxides (juvenile hormones) and ecdysteroids (ecdysone, 20-... 

Unsymmetrical trans vinyl halides have been prepared from acetylenic alcohols by Corey and co-workers (as illustrated in the accompanying formulation) in connection with their synthesis of farnesol and Gecropia juvenile hormone. Several syntheses of vinyl halides (with... 

Methyl (2 6 .10 -10 1 l-epoxy-3 7,ll-trimethyltridecadienoate (the juvenile hormone of the tobacco homworm)... 

Stereospecific Synthesis of Trisubstituted Olefins from Acetylenes or Aldehydes Applications to the Total Synthesis of Cecropia Juvenile Hormones (JH) and Farnesol... 

This remarkable process allows the joining of three components in one synthetic step. This methodology was applied to the syntheses of several juvenile hormones and famesol. 

Epoxyfarnesol was first prepared by van Tamelen, Stomi, Hessler, and Schwartz 4 using essentially this procedure. It is based on the findings of van Tamelen and Curphey5 that N-bromosuccinimide in a polar solvent was a considerably more selective oxidant than others they tried. This method has been applied to produce terminally epoxidized mono-, sesqui-, di-, and triterpene systems for biosynthetic studies and bioorganic synthesis.6 It has also been applied successfully in a simple synthesis of tritium-labeled squalene [2,6,10,14,18,22-Tetracosahexaene, 2,6,10,15,19,23-hexamethyl-, (all-E)-] and squalene-2,3-oxide [Oxirane, 2,2-dimethyl-3-(3,7,12,16,20-pentamethyl-3,7,ll,-15,19-heneicosapentaenyl)-, (all-E)-],7 and in the synthesis of Cecropia juvenile hormone.8... 

The reaction of the phenylsulphinyl allylic lithium a-carbanion 342 with oxiranes was found by Guittet and Julia to give, after rearrangement and desulphurization, dihydroxy-dienes 343427 (equation 197). Demoute and coworkers have described the alkylation reaction of a very sophisticated 2-alkenyl sulphoxide 344 as a part of the total synthesis of a juvenile hormone 345428 (equation 198). Since the allylic sulphoxide carbanion has an ambident character, the alkylation may occur sometimes also at the y-position. This direction of alkylation is observed in the case of acyclic allylic sulphoxide anions 346, and results in the formation of the corresponding allylic sulphoxide 347 and vinylic sulphoxide 348423 (equation 199). 

The use of polylactides for delivery of insect hormone analogs and other veterinary compounds (115,116) has been studied. Microspheres, pellets, and reservoir devices based on polyglycolide, poly-(DL-Iactide), poly(L-lactide), and various copolymers have been used to deliver methoprene and a number of juvenile hormone analogs. ... 

The precocenes, e,g. (39), are the opposite of juvenile hormones in that they stimulate a juvenile Insect to become an adult. There is some hope that premature application of precocenes might lead to sterile adults and hence control of that species. 

Where would you make the first disconnection to devise a convergent synthesis for (14), whose epoxide is the cecropia juvenile hormone What reaction and what starting materials might you use ... 

Of the ten published syntheses of juvenile hormone, only one uses this disconnection first, though many use it later in a more linear approach. These workers used route (b), made (15) by alkylation of another phos-phonium salt, and used a reconnection strategy for (16), Analysis of (lb)... 

The jS-oxido-ylides synthesis of trisubstituted olefins has also been applied to the synthesis of farnesol (127). The phosphonium salt (123) with the aldehyde (124) and formaldehyde gave the hydroxy farnesol derivative (125) which was transformed into farnesol (127) and into (126), a position isomer of Cj juvenile hormone. 

The phosphonate (176) has been used for the addition to aldehydes of a masked jS-keto-ester function and applied in the synthesis of ( )-7(f),9(t)-trisporic acid B methyl ester. The isomerically pure phosphonate (177) has been used in a synthesis of dehydro-Cig juvenile hormone," the anion being generated by treatment with lithium di-isopro-pylamide in THF-HMPT at - 65 °C for 1 min. 

Stable in acidic, neutral and basic aqueous solutions Pale yellowish solid, faint characteristic odor Flash point 119°C (Pensky-Martens closed tester) Pyriproxyfen is an insect growth regulator which acts both as an ovacide and as an inhibitor of development (juvenile hormone mimic) against white flies, scale, and psylla. The specificity of pyriproxyfen, and its low mammalian toxicity, allow for some variation in application timing. For example, the lack of toxicity to bees allows pyriproxyfen to be applied during bloom on apple trees, and its low mammalian toxicity allows for a very short pre-harvest interval on citrus The residue definition is for pyriproxyfen alone... 

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