Abstract: Mandipropamid is the first mandelamide fungicide on the market. Two series of novel N-substitued benzyloxy-α-alkoxy phenylacetamide compounds and α-subsitued benzylamino-phenylacetamide compounds, the bioisosteric analogues of Mandipropamid, have been synthesized from Vanillin and mandelic acid by substitution, reduction and so on. Their structures were characterized and determined by 1H NMR, HRMS. The result of the preliminary biological activity tests showed that some of the compounds exhibited some anti-fungal activities. For example, N-(3-methoxyl-4-ethoxylbenzyloxy)-α-ethoxyl-4-chloride-phenylacetamide had inhibition rate 90% against fungicidal activity at the concentration of 200 ug /mL. N-(3-methoxyl-4-ethoxylbenzyloxy)-α-isopropoxy-4-chloride-phenylacetamide had inhibition rate 80% against phytophthora capsici at the concentration of 20 ug /mL.

Key words: Phenylacetamide, Mandelamide, Synthesis, fungicide