(E)-α-(Methoxyimino)-2-[1-(aryloxy)methyl]-benzeneacetates, the analogues of Kresoxim-methyl, were stereoselectively synthesized with the coupling reaction of 2-methylphenyldiazonium chloride and methyl 2-hydroxyiminoacetate in the presence of CuSO_ 4 /Na_ 2 SO_ 3 as a key step, and it was first found that the coupling reaction could give the key intermediate material(E)-and(Z)-methyl 2-(hydroxyimino)-2-o-tolylacetate with a molar ratio of 14∶1. The(E)-configurations of all these compounds were assigned on the basis of their 2D-NOESY spectra of 1 H NMR. The preliminary bioassays indicate that most of the compounds show an activity against a wide variety of fungi.
LI YanLIU JieZHOU Ye-bingZHANG Hong-quanCHEN Zu-xinLIU Zhao-jie
Intestinal absorption of two oxovanadium complexes, vanadyl acetylacetonate (VO(acac)2) and bis (maltolato)-oxovanadium (VO(ma)2), has been compared using Caco-2 monolayers as a model system. The two compounds are similar in chemical structures but different in glucose-lowering effects. Our experimental results show that they are both transported via passive diffusion with apparent permeabilty coefficients (apical→basolateral) of (82.0 ± 6.7)× 10-7 and (14.6 ± 0.7)× 10-7 cm· s-1, respec-tively. This suggests that absorptivity of VO(acac)2 is much higher than that of VO(ma)2. This difference may be related to the metabolism of either compound, or its ligand, or both in the course of the transport. However, This difference in absorption will cause the great difference in bioavailability,which might account for better efficacy of VO(acac)2 than VO(ma)2 as the insulin-mimic agent.
