Synthesis of Linear Geranylphenols and Their Effect on Mycelial Growth of Plant Pathogen Botrytis cinerea

Molecules

Luis Espinoza¹  Lautaro Taborga¹  Katy D໚z¹  Andrés F. Olea² 

[1] Departamento de Química, Universidad Técnica Federico Santa María, Av. España No. 1680, Valparaíso 2340000, Chile; E-Mails:;Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andrés Bello, Quillota 980, Viña del Mar 2520000, Chile; E-Mail:

关键词: synthesis;    linear geranylphenols;    antifungal activity;    Botrytis cinerea;   

DOI  :  10.3390/molecules19021512

来源: mdpi

【 摘 要 】

Natural geranyl compounds are known to exhibit important biological activities. In this work a series of geranylphenols were synthesized to evaluate their effect on the mycelial growth of Botrytis cinerea. Geranyl derivatives were synthesized by direct geranylation reactions between the corresponding phenol derivatives and geraniol, using BF₃^.OEt₂ as catalyst and AgNO₃ as secondary catalyst. Previously reported molecules [geranylhydroquinone (2), geranylhydroquinone diacetate (6) and geranylphloroglucinol (9)], and new substances [(E)-4-(3,7-dimethylocta-2,6-dienyl)benzene-1,2,3-triol (geranyl-pyrogallol, 7), (E)-4-(3,7-dimethylocta-2,6-dienyl)benzene-1,2,3-triyl triacetate (8), (E)-2-(3,7-dimethylocta-2,6-dienyl)benzene-1,3,5-triyl triacetate geranylphloroglucinol triacetate (10), 2,4-bis((E)-3,7-dimethylocta-2,6-dienyl)benzene-1,3,5-triyl triacetate (11), 2,6-bis((E)-3,7-dimethylocta-2,6-dienyl)-3,5-dihydroxyphenyl acetate (12)], were obtained. All compounds were characterized by IR, HRMS and NMR spectroscopic data. The inhibitory effect of the synthesized compounds on the mycelial growth of Botrytis cinerea was tested in vitro. Excepting compound 11, all substances constrained the mycelial growth of Botrytis cinerea. The antifungal activity depends on the chemical structure of geranylphenol derivatives. Compounds 2 and 9 were the more effective substances showing inhibition degrees higher than those obtained with the commercial fungicide Captan, even at lower concentrations. Monosubstitution on the aromatic nucleus by a geranyl chain seems to be more effective for the inhibition of mycelial growth than a double substitution. These results suggest that the new derivatives of geranylphenols have the ability to block the mycelial development of the plant pathogen B. cinerea and that this capacity depends strongly on the structural features and lipophilicity of the compounds.

【 授权许可】

CC BY   
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