Insect Pest Management Agents:  Hormonogen Esters (Juvenogens)

Abstract

The chemical part of this investigation focused on designing structures and synthesizing a series of six new esters (juvenogens), derived from biologically active insect juvenile hormone bioanalogues (juvenoids, JHAs) and unsaturated short-chain linear and branched fatty acids for possible application as biochemically targeted insect hormonogen agents. The structures of the new compounds were assigned on the basis of a detailed NMR analysis of their (1)H and (13)C NMR spectra. The biological part of this investigation focused on introductory biological screening tests with these compounds against the red firebug (Pyrrhocoris apterus), termites (Reticulitermes santonensis and Prorhinotermes simplex), and the blowfly (Neobellieria bullata). The biological activity of the juvenogens was studied in relation to the fatty acid functionality in the structures. Notable biological activity in topical tests and medium activity in peroral tests was found for the juvenogens 3 and 7 with P. apterus. The compounds 6 and 8 showed the lowest activity in both topical and oral assays with P. apterus. Considerable effect of all tested juvenogens was observed in P. simplex; however, the juvenogens 5 and 6 (derivatives of the only branched short-chain fatty acid) showed no activity against R. santonensis. The effect of the compounds 3-8 on larval hatching of N. bullata was only moderate (larval hatching 80-90%); however, the proliferation effect caused by 5, 6, and 8 is more pronounced than the effect caused by 3, 4, and 7.

Peptide-Based Technologies to Alter Adenoviral Vector Tropism: Ways and Means for Systemic Treatment of Cancer

“…Applying this technology against whole-living cells in vitro or in vivo allows direct selection of aptamers even against rare antigens without prior purification of membrane-bound targets, access to membrane proteins in their native conformation and identification of targets related to a specific phenotype. Their thermal stability, low cost, unlimited applications and high binding affinity to disease-associated proteins or non-protein targets [32,77,78,79] make them attractive, even in clinical trials for the treatment of distinct medical conditions, as reviewed very recently [80,81,82]. The potential of aptamers as a valid tumor targeting gene delivery system with high transduction efficiency was summarized by [83,84].…”

Novel Juvenogens (Insect Hormonogenic Agents): Preparation and Biological Tests on Neobellieria bullata

“…The samples were dissolved in deuteriochloroform using tetramethylsilane (δ = 0.0 ppm for 1 H) and a central line of a signal of the solvent (δ = 77.0 ppm for 13 C) as internal references. Signals in 13 C NMR were assigned to the corresponding carbon atoms by the heteronuclear multiple-quantum coherence (HMQC) measurement on a Bruker AVANCE 500 MHz instrument. Multiplicity is described by the following abbreviations: s for singlet, d for doublet, dd for doublet of doublets, t for triplets, q for quartet, and m for multiplet.…”

“…bullata, similarly as it had already been studied with earlier juvenogens , . Generally, the mode of action of these juvenogens leads to physiological and morphological changes of eggs, which can be presented in the form of a statistical evaluation of the hatchability and can be demonstrated in a form of a histological analysis of ovaries and eggs ,, .…”

“…cas.cz. eggs, which can be presented in the form of a statistical evaluation of the hatchability and can be demonstrated in a form of a histological analysis of ovaries and eggs (10,12,13).…”

UHPLC–MS Analysis of Juvenile Hormone II in Mediterranean Corn Borer (Sesamia nonagrioides) Hemolymph Using Various Ionization Techniques

“…4,5 This compound, as for other JHs, is an acyclic sesquiterpenoid that regulates important processes related to the development, production of eggs in the female's ovaries, diapauses, and other aspects of the physiology of the insects. The determination of the JH levels in different developmental stages is essential to study the different aspects of insect development, to obtain new bioanalogue derivatives of the different JHs, 7 and to apply this knowledge to pest control. 8 Numerous analytical techniques have been used to detect and quantitate JH in hemolymph.…”