Development of novel pesticides based on phytoalexins: Part 2. Quantitative structure–activity relationships of 2‐heteroaryl‐4‐chromanone derivatives

Abstract

Phytoalexins are low-molecular-weight chemicals that immune systems of plants produce and accumulate in response to infections, especially those of fungal origin. Although their content is not high in plants, yet they have shown unique fungicidal activity and played an important role in the defence system of plants. In searching for novel environmentally benign fungicides with high activity, the structures of flavanone derivatives, one of the most important phytoalexins groups, have been modified via bioisosteric substitution and a series of 2-heteroaryl-4-chromanones were designed and synthesized. They showed good fungicidal activities against rice blast disease, Pyricularia grisea (Sacc). Their IC50 values were tested in vitro and the relationship between structure and fungicidal activity was analyzed quantitatively using a Hansch-Fujita approach. The results showed that hydrophobicity was very important for fungicidal activity and there is apparently an optimum hydrophobic property for the molecules at a log Pow value of about 2.7. In addition, the results indicated that electronic effects played an important role in binding with the receptor and that the C=O group was probably a electron-accepting site. The quantitative structure-retention correlative equation of the title compounds was also established.

Antifungal Activity of Resveratrol against Botrytis cinerea Is Improved Using 2-Furyl Derivatives

“…Earlier studies found an apparently optimum hydrophobic effect for antifungal activity as molecules with high and low Log P value were less active [24]–[26]. In our study, molecules with a Log P value slightly higher than 4.0 showed higher antifungal activities against B. cinerea , compared to resveratrol (log P of 3.0).…”

Quantitative structure–activity relationship studies of mushroom tyrosinase inhibitors

“…CoMFA and CoMSIA are widely used for studying quantitative structure-activity relationships at the 3D level [29][30][31][32][33]. CoMFA and CoMSIA models were derived from a set of 38 structurally similar compounds, and 10 compounds were selected as a test set for model validation.…”

Synthesis of 3‐Thiophenchromone by Stille Cross‐coupling Palladium on Charcoal‐Catalyzed Ligand‐Free

“…Heteroarylchromones as the derivatives of arylchromones show the activities of antifungal , pesticidal and Gastroprotective agents . Yokoe, I. etal .…”