Abstract: Maleated rosin was prepared by using rosin,a natural product,as starting material.Then,ten novel maleated rosin-based dithiourea-amidecompounds 7a-7j were synthesized via a multiple-step process.The targeted compounds were analyzed and characterized by FT-IR,¹H NMR,¹³C NMR,ESI-MS,and UV-vis.The preliminary bioassay showed that,at the concentration of 50 μg/mL,the targeted compounds exhibited a certain antifungal activity against the five tested phytopathogens.Most of the compounds displayed inhibition rate of more than 60% against Physalospora piricola,in which compound 7i had inhibition rate of 71.4% (B-class activity level).

Key words: rosin, dithiourea-amide, synthesis, antifungal activity