ABSTRACT
In the title compound, C27H27BrFNO4, which is an inhibitor of acetyl-CoA carboxyl-ase, the cyclo-hexane ring displays a chair comformation with the spiro-C and meth-oxy-bearing C atoms deviating by 0.681â (7) and -0.655â (1)â Å, resppectively, from the mean plane formed by the other four C atoms of the spiro-C6 ring. The mean planes of the cyclo-hexane and 2-bromo-4-fluoro-phenyl rings are nearly perpendicular to that of the pyrrolidine ring, making dihedral angles 89.75â (6) and 87.60â (9)°, respectively. In the crystal, mol-ecules are linked via pairs of N-Hâ¯O hydrogen bonds, forming inversion dimers.
ABSTRACT
In the title compound, C18H23NO3, the cyclo-hexane ring has a chair conformation. The oxirane plane (OCC) makes a dihedral angle of 76.15â (13)° with that of the pyrrolidine ring to which it is fused. The mean plane of the cyclo-hexane ring and the benzene ring are almost normal to the pyrrolidine ring, with dihedral angles of 88.47â (8) and 77.85â (8)°, respectively. In the crystal, mol-ecules are linked via pairs of N-Hâ¯O hydrogen bonds, forming inversion dimers. These dimers are linked via pairs of C-Hâ¯O hydrogen bonds, forming chains along the a-axis direction.
ABSTRACT
BACKGROUND: In previous studies, scientists found that, when spirotetramat was introduced into plants or animals, it was mainly metabolised at positions C-4 and C-8. That is to say, these two functional positions potentially played an important role in spirotetramat's bioactivities. In order to develop novel insecticides or miticides, the present authors designed and synthesised 35 spirotetramat analogues based on metabolite structures. RESULTS: All of the analogues have been identified on the basis of (1)H NMR, ESI-MS and elemental analysis data. The activities of these analogues were evaluated against three organisms, and biological assays indicated that compounds 5f, 5h and 5u possessed better insecticidal activities against bean aphids (Aphis fabae) than the lead compound spirotetramat. The LC50 of 5f, 5h and 5u against bean aphids reached 0.42, 0.28 and 2.53 mg L(-1) respectively. Moreover, some compounds possessed comparable activities against carmine spider mite (Tetranychus cinnabarinus) and oriental armyworm (Mythimna sepatara) with spirotetramat. The structure-activity relationships (SARs) indicated that the flexible bridge at position C-4 of spirotetramat was important for its bioactivities, and the size of the group at position C-8 would have great influence on the activities. Furthermore, the log P values lower than 6.0 may be favourable for insecticidal activities. CONCLUSION: The present work demonstrates that some spirotetramat analogues can be used as potential lead compounds for developing novel insecticides, and preliminary SAR analysis would provide information for the utilisation of spirotetramat analogues as potential lipid biosynthesis inhibitors.