QSAR of 2,4-diphenyl-1,3-oxazolines for ovicidal activity against the two-spotted spider mite Tetranychus urticae

Abstract

Ovicidal activity of 2,4-diphenyl-1,3-oxazoline congeners with various substituents on the 4-phenyl ring against two-spotted spider mites Tetranychus urticae was quantitatively analyzed using the classical QSAR (HanschFujita) method. In QSAR analysis, hydrophobicity in terms of log P (P: partition coefficient between 1-octanol and water) was the most significant parameter with its square term. The optimum log P value for 2,4-diphenyl-1,3-oxazoline analogs was evaluated as about 7.1. The introduction of substituents with inductive electron-withdrawing properties was also favorable to activity, but the presence of substituents at the ortho-and meta-positions was not promising.

Exploring 2D and 3D QSARs of 2,4‐Diphenyl‐1,3‐oxazolines for Ovicidal Activity Against Tetranychus urticae

“…The ovicidal activity data (LC 50 ) of 90 2-(2',6'-difluorophenyl)-4-phenyl-1,3-oxazoline derivatives [7] were converted to reciprocal logarithmic values [pLC 50 ¼ À log LC 50 (M)] which have been used for the QSAR analysis. There is only one region of structural variations in the compounds, which is the R position of the phenyl ring.…”

“…We have performed QSAR studies on the dataset reported by Suzuki et al [7] with 2D (physicochemical, structural, and topological) and 3D (shape, spatial, electronic, and molecular field) descriptors. The categorical list [13] of descriptors used in the development of QSAR models was reported in Table 2.…”

“…Suzuki et al [7] worked on the same dataset eliminating four compounds (compounds 36 -38, 45) as outliers and generated classical QSAR models on the basis of remaining 86 compounds. They used hydrophobic (p and log P), electronic (s), steric (E s and STERIMOL) parameters and some indicator variables (I o , I m , I p ).…”

“…A number of acaricides with various modes of action have been developed to control these mites. Among them, acaricides that inhibit the growth and molting of mites, flucycloxuron [4], flufenoxuron [5], and hexythiazox [6] are a few examples of this class of insecticides, because they are effective against strains resistant to respiratory inhibitors and neurotoxic compounds, and are thought to be safe for mammals [7].…”

“…Recently, Suzuki et al [7] have developed classical QSAR models of 2-(2',6'-difluorophenyl),4-phenyl-1,3-oxazoline derivatives for the ovicidal activity against T. urticae by using hydrophobic (p and log P), electronic (s), steric (E s and STERIMOL) parameters and some indicator variables (I o , I m , I p ). In the present paper, we have performed further QSAR studies on the dataset reported by Suzuki et al [7] with 2D (physicochemical, structural, and topological) and 3D (shape, spatial, electronic, and molecular field) descriptors to get a deep insight into the SARs.…”