Structure–activity relationship study of synthetic hydrazines as ecdysone agonists in the control of spruce budworm (Choristoneurafumiferana)

Abstract

A quantitative structure-activity relationship study was performed for a number of aroylhydrazine compounds with respect to their biological activity against spruce budworm. It was found that the biological activity can be modulated by substituents on the aromatic rings. Substituents with high .ir value and small L value lead to increase in biological activity. Molecular mechanics calculations were used to explain how the active compounds may mimic the strong-binding Y region of ecdysone.Key words: spruce budworm, ecdysone, agonist, hydrazines, quantitative structure-activity relationship.RCsumC : On a effectuC une Ctude de la relation quantitative structure-activiti d'un certain nombre de composCs aroylhydrazines par rapport 2 leur activitC biologique contre tordeuse d'kpinette. On a trouvC que l'activitt peut Etre modulCe par les substituants attachts au noyaux aromatiques. Les substituants avec des valeurs ClevCes de .ir et des valeurs de L faibles augmentent llactivitC biologique. On a utilisC des calculs de mCcanique molCculaire pour expliquer comment les composts actifs peuvent mimer la rCgion Y de forte liaison de l'ecdysone.

Molecular Modeling Study on the Structure−Activity Relationship of Substituted Dibenzoyl-1-tert-butylhydrazines and Their Structural Similarity to 20-Hydroxyecdysone

“…The procedure used for the molecular modeling study was PCMODEL, (fourth edition, June 1990) of Serena Software (Bloomington, IN). The iterative energy minimization of molecular structure was carried out by using the MMX-Minimize program (Mohammed-Ali et al, 1995). All conformations, energies (E, kcal/mol), dihedral angles (deg), and bond lengths (Å) were obtained after running MMX-Minimize.…”

“…Some researchers believed that the effects of substituents at the benzoyl moiety on activity were more complicated, and it was difficult to explain the difference in activity between mono-or disubstituted and multisubstituted with multivariables and one unified QSAR equation (Oikawa et al, 1994a). Other researchers believed that biological activity correlates mainly with π value (lipophilic character) and L value (steric effect); high π and low L values would increase the activity, and, of course, the involvement of π values will improve the correlation coefficient (Mohammed-Ali et al, 1995).…”

“…Recently, nonsteroidal 1,2dibenzoyl-1-tert-butylhydrazine and its congeners (SBH), as a new class of insecticides having totally different structures, were found to mimic the action of 20-HE to activate the ecdysone receptor (Wing et al, 1988a;Spindler-Barth et al, 1991), leading to lethal premature molting (Kubo et al, 1983;Chandler et al, 1992;Darvas et al, 1992); the former was found to be more potent than the latter (Wing et al, 1988b). Some researchers have studied the synthesis and quantitative structureactivity relationship of several substituted 1,2-dibenzoyl-1-tert-butylhydrazines (Oikawa et al, 1994a,b;Mohammed-Ali et al, 1995); it was found that the effects of substituents on activity were a very complicated case, as various effects, e.g. molecular hydrophobicity and steric and electronic factors, seemed to overlap (Oikawa et al, 1994a).…”

Ecdysone Agonists: Mechanism and Biological Activity

“…However, up until now, no clear conclusions can be drawn of whether 20E and substituted dibenzoyl hydrazines are perceived in a similar manner for EcR bin ding by insects although they possess a similar ecdysteroid activity. On this matter, Chan et al (1990) and Mohammed-Ali et al (1995) expected that ligand and receptor interactions depend on the molecular crystalligand structure. Recently, Oikawa et al (1994a,b), Nakagawa et al (1995) and Smagghe et al (unpubl.…”

Synthesis and Insecticidal Activity of 3, 5-Dimethylbenzoyl Moiety Modified Analogues of <i>N</i>-<i>tert</i>-Butyl-<i>N</i>′-(4-ethylbenzoyl)-3, 5-dimethylbenzohydrazide

“…2). In this paper we describe the preparation of fourteen new B-ring-modified RH-5992 analogues (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) and also their insecticidal activity against the common cutworm (Spodoptera litura). MATERIALS AND METHODS…”