Synthesis, Antifungal Activity, 3D-QSAR and Controlled Release on Hydrotalcite Study of Longifolene-Derived Diphenyl Ether Carboxylic Acid Compounds

Abstract

Twenty-two novel longifolene-derived diphenyl ether-carboxylic acid compounds 7a–7v were synthesized from renewable biomass resources longifolene, and their structures were confirmed by FT-IR, 1H NMR, 13C NMR, and HRMS. The preliminary evaluation of in vitro antifungal activity displayed that compound 7b presented inhibition rates of 85.9%, 82.7%, 82.7%, and 81.4% against Alternaria solani, Cercospora arachidicola, Rhizoctonia solani, and Physalospora piricola, respectively, and compound 7l possessed inhibition rates of 80.7%, 80.4%, and 80.3% against R. solani, C. arachidicola, P. piricola, respectively, exhibiting excellent and broad-spectrum antifungal activities. Besides, compounds 7f and 7a showed significant antifungal activities with inhibition rates of 81.2% and 80.7% against A.solani, respectively. Meanwhile, a reasonable and effective 3D-QSAR mode (r2 = 0.996, q2 = 0.572) has been established by the CoMFA method. Furthermore, the drug-loading complexes 7b/MgAl-LDH were prepared and characterized. Their pH-responsive controlled-release behavior was investigated as well. As a result, complex 7b/MgAl-LDH-2 exhibited excellent controlled-releasing performance in the water/ethanol (10:1, v:v) and under a pH of 5.7.

Synthesis and Biological Activity Evaluation of Novel Chalcone Analogues Containing a Methylxanthine Moiety and Their N-Acyl Pyrazoline Derivatives

“…Xylostella and fungicidal activity at 50 μg/mL against Physalospora piricola, respectively. These activities were expressed in terms of D by the formula D = log­( I /((100 – I ) × M w )), , where I is the lethality rate or inhibition rate and M w is the molecular weight of the tested compounds. For insecticidal activity data, of the 28 compounds, 17 compounds were used as a training set, and 9 compounds were used as a test set.…”

“…44 Taking into account the diversity of structures and bioactivity potentials of the target compounds I and II, twenty-eight and thirty-seven compounds were used for 3D-QSAR analysis based on the two series of data, insecticidal activity at 10 mg/L against P. Xylostella and fungicidal activity at 50 μg/mL against Physalospora piricola, respectively. These activities were expressed in terms of D by the formula D = log(I/ ((100 − I) × M w )), 45,46 where I is the lethality rate or inhibition rate and M w is the molecular weight of the tested compounds. For insecticidal activity data, of the 28 compounds, 17 compounds were used as a training set, and 9 compounds were used as a test set.…”