Juvenile hormone activity

Farnesol derivatives also have juvenile hormone activity. 

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. 

Juvabione is a terpene-derived ketoester that has been isolated from various plant sources. There are two stereoisomers, both of which occur naturally with R-configuration at C(4) of the cyclohexene ring and are referred to as erythro- and f/trao-juvabione. The 7(.S )-cnan(iomcr is sometimes called epijuvabione. Juvabione exhibits juvenile hormone activity in insects that is, it can modify the process of metamorphosis.18... 

Kraker, J. J., Hawkins, D. M., Basak, S. C., Natarajan, R., Mills, D. Quantitative structure-activity relationship (QSAR) modebng of juvenile hormone activity Comparison of validation procedures. Chemometr. Intell. Lab. Syst. 2007, 87, 33M2. 

Juvenile hormone activity. Acetone extract of the dried stem produced weak activity on Dysdercus cingulatus °. ... 

Juvebione, a product of the balsam fir with juvenile hormone activity... 

Biggers, W. J. and Laufer, H., Chemical induction of settlement and metamorphosis of Capitella capitata Sp. 1 (Polychaeta) larvae by juvenile hormone-active compounds, Invertebrate Reprod. Dev., 22, 39, 1992. 

Examples of applications of this strategy are given below, a) The unsymmetrical ketone juvabione, a molecule which possesses high juvenile hormone activity, has been synthesized from two readily-available alkenes (Equation B3.9). (The chiral centre present in the first alkene that reacts with thexylborane does not exert any control over which face of the... 

Two other new nuclear receptors have been shown to increase epidermal differentiation the LXR and the FXR. Farnesol and juvenile hormone activate the FXR leading to improved epidermal differentiation. Two genes encode for the LXR proteins, LXR alpha and LXR beta, and both are activated by various oxysterols the most potent being 22(R)-hydroxycholesterol, 24(S)-hydroxycholesterol, 24(S) 25-epoxycholesterol and 7-hydroxy cholesterol. Cholestenoic acid also acts on this receptor. In vitro these agents also increased epidermal filaggrin levels.129,130... 

The syntheses described above and the individual reaction steps, respectively, are the historical basis for the development of the synthesis of isoprenoid juvenile hormones. In addition to the latter, a great number of naturally occurring or synthetic analogous substances as well as non-isoprenoid compounds with juvenile hormone activity can also be obtained via Wittig reaction. However, since these syntheses do not offer basically new aspects with respect to the olefination step, they are not further discussed here. 

Interesting substances possessing juvenile hormone activity against hemipteran bug have been detected in conifers belonging to Abies species (-F)-Juvabione [methyl ester of (-F)-todomatuic acid], isolated from balsam and Japanese fir wood, may have potential use for insecticidal applications. A related compound have been isolated from Douglas fir wood. 

The two naturally occurring drug and insecticide adjuvants, sesamin and sesamolin from sesame oil, were found to posses modest juvenile hormone activity and served as models for the design of the first aromatic juvenile hormone analogs (12. 13.). 

Table I. Phytochemicals with Juvenile Hormone Activity...

A number of inhibitors of methyl farnesoate epoxidase of Blaberus glganteus corpora allata have been described (18). They include typical cytochrome P-450 monooxygenase inhibitors such as methylenedloxyphenyl compounds and substituted imidazoles. In assays of JH III biosynthesis by Perlplaneta amerlcana CA in vitro some methylenedloxyphenyl compounds were shown to inhibit hormone production at moderate to high concentrations (19). Both methylenedloxyphenyl compounds and terpenoid imidazoles have also some anti-juvenile hormone activity in Lepidoptera (7, 20). 

Several simple p-alkylphenyl ethers of geraniol epoxide have been found to possess juvenile hormone activity. The p-ethylphenyl ether, tested on the yellow... 

A simple and efficient synthesis of juvabione (58) (c/. Vol. 1, p. 60 Vol. 5, p. 49 Vol. 4, p. 88), a sesquiterpenoid possessing juvenile hormone activity, has been achieved using a combination of hydroboration and carbonylation reactions cf. Scheme 6). A new efficient synthesis of ( )-a-curcumene (59) cf. Vol. 5, p. 51) involves reduction in situ (Li-NHs) of the alkoxide produced from p-tolylmagnesium bromide and 6-methylhept-5-en-2-one. ... 

Natural products such as the avermectins and milbemycin produce very active insecticides. Chemistry in this area is presented in one chapter. Juvenile hormone activity (36) still is of interest, and current work is described in this field. 

Bowers, W.S. fL96H). Juvenile hormone activity of natural and synthetic svnergists. i ci-enee 168, 895 - 897. 

Redfem, R.E., McGovern, T.P. and Bcroza, M. (1969). Juvenile hormone activity ol Sesame and related compounds in tests nn the yellow mealworm. / Econ. Entomoi. 63. 540-545. 

Shekhter, O.V., Tsizin, Y.S., and Pridantseva, E.A., Compounds with juvenile hormone activity. Part... 

Shekhter, O.V., and Tsizin, Y.S., Compounds with juvenile hormone activity. Part 7. Synthesis of some derivatives of 3,ll-dimethyl-10,ll-epoxy-2-dodecenoic acid, Zh. Obshch. Khim., 45, 1180, 1975 J. Gen. Chem. USSR (Engl. Transl.), 45, 1161, 1975. 

Findlay, J.A., Epoxidized hydrocarbon acid esters having juvenile hormone activity. Findlay, U.S. Patent Appl. US 3761495, 1973 Chem. Abstr, 80, 37332. 1974. 

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