Fenazaquin

The discovery of fenazaquin (EL-436, XDE-436 Table 28.3.1) resulted from yet another approach. In the early 1980s as part of Elanco s random screening program a quinazoline, LY-176771, was found to exhibit some fungicidal activity against 

The 4-chloroquinazoline is coupled to the side chain 4-tert-butylphenylethanol with the aid of anhydrous HCl [43], This gives fenazaquin as the HCl salt, which is liberated as the free base with aqueous ammonia. 

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The ascaracide fenazaquin 1175 is active against several spider mite species, while DPC-083 (BMS 561390) 1176 is an anti-HIV reverse transcriptase inhibitor <2000JME2019>. The quinazoline 1177 has recently been identified as a lead compound for the development of selective inhibitors of lymphocyte-specific kinase (Lck) which is involved in T-cell-mediated autoimmune and inflammatory disease <2006JME5671>. 

Formaldehyde acetochlor, alachlor, azamethiphos, azinphosmethyl, bisthiosemi, butachlor, butenachlor, carbophenothion, dazomet, 2.4 D B, dichlorphen, glyphosate, IPSP, oxolinic acid, penconazole, phorate, phosalone, phosmet, piperonyl, butoxide, tetramethrin Formamide fenazaquin, triforine Formanilide mepanipyrim, pyrimethanil... 

Quinazoline (4 hydroxy) fenazaquin Quinoline (7 chloro 3.8 dimethyl) quinmerac Quinoline (7 chloro 8 methyl) quinclorac Quinoline, 2.3 dicarboxilic acid imazaquin Quinoxaline quinomethionate, quizalofop-ethyl Quinoxaline (2.6 dichloro) propaquizafop, quizalofop Quinoxaline (6 methyl 2.3 dichloro) chinomethionate Quinoxaline (2 hydroxy) quinalphos Quinoxaline (2 hydroxy, 6 chloro) propaquizafop... 

Quinazoline acaricides are derivatives of quinazoline. Fenazaquin is the only member of this unique class. It is a contact and stomach poison acaricide used for control of all stages of mites on cotton, stone and pome fruits, citrus, grapes, and ornamentals. Its oral LD50 in rats is 134-138 mg/kg. 

Mitochondrial electron transport system Rotenone, hydramethylnon, Pyridaben, tolfenpyrad, HCN, phosphine, acequinocyl, fenazaquin, pyrimidifen, tebufenpyrad, fenpyroximate, fluacrypyrin Inhibition... 

The fused pyrimidine derivatives of fenazaquin (109), derived from 1-aminobenzoic acid, are useful miticidal agents71. 

Whereas fenazaquin (1) is a well-known complex I inhibitor, the primary mode of action of quinoxyfen (21) is, as yet, unknown. Although the lepidine compound 22 (Fig. 13.5.8) shows sub-micromolar activity level Ustilago maydis -IC50 0.73 pmol) in the biochemical complex I assay, the activity level in glasshouse tests is not satisfying at all. 

Fenazaquin, Fenpyroximate, Pyrimidifen, Pyridaben, Tebufenpyrad, Tolfenpyrad Rotenone... 

For the acaricide fenazaquin [4-(4-tert-butylphenethoxy)quinazoline], a potent inhibitor of electron transport at complex I (see Section 28.1.3), an additional low-affinity binding site in the stalk region of ATP synthase has been recently identified. The relevance of this newly discovered binding site is unknown since the enzymatic activity of ATP synthase is not impaired [12]. 

Scheme 28.3.3 shows the synthesis of fenazaquin. The quinazoline ring is formed by the condensation of anthranilic acid with formamide and subsequent... 

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