Research And Development Of The Novel Biaorational Fungicide-Propamidine

Aromatic diamidines have a long history in the treatment of human diseases. These diamidines also display a useful spectrum of antitrypanosomal and antiviral activity. Both severe acute and chronic side effects are associated with parenteral administration, which restricted them to application in the treatment of human diseases. In prophase research, pentamidine, one of these diamidines, antifungi activity was discovered . So these research mainly trying to research and development of these diamidines fungicide. The results of the research and development show as fellows: 1 The betamidine, propamidine, butamidine, pentamidine had been synthesized. They anti-fungi activity against plant pathogenic Botyrtis cinerea had been tested. The median effective concentration (EC50) of inhibition to mycelium development was 44.7484mg/L,2.1599mg/L,0.6821mg/L and 10.3700mg/L, respectively. The EC50 of inhibition to spore bourgeon was 1.2616 mg/L,2.7510mg/L,5.7362mg/L and 2.0767mg/L, respectively. The protective and therapy effectiveness had been experimented in vitro, and the chemicals showed different effectiveness, the propamidine and butamidine were better than others. The results of field experiments showed that propamidine and butamidine had higher control effectiveness to the disease than betamidine and pentamidine. But, the synthesis cost of propamidine is fewer than butamidine. Therefore, propamidine was selected for R&D compound. 2 After studied on the synthesis techniques of propamidine in laboratorial scale, the pilot production line had leagued with 20L tank and other equipments, then completed the pilot synthesis techniques was researched. A optimized pilot synthesis techniques meeting with industrialization demand had been established.The techniques had merits of abundance raw materials, short synthesis procedure, moderation condition, simple unit operations, etc. 3 The suitable pesticide formulation of propamidine was studied, which was soluble concentration, contain 2% propamidine. So that the formulation was 2% propamidine SL. A HPLC methode was developed to analysis the propamidine, C18 chromatographic column, water: methanol(75:25, contain 0.0025mol/L sodium lauryl) mobile phase, flow rate 1.0 mL/min, uv detector. The quality index of propamidine and 2% propamidine SL products had established, and the criterion of the products was authorized. 4 The field activity to Botyrtis cinerea on tomato, cucumber and strawberry was experimented in shaanxi and guizhou province. The result demonstrated that the 2% propamidine SL had high effectiveness to the diseases. When treated with 6～12(ai)g /mu, it can reduce the disease index by 70-85%, applied in the initial stages of Botyrtis cinerea. The 2% propamidine SL was very safety to the vegetables, and had stimulated effect to the growth of plant. There were a little dust on leafs of plant after applying the formulation. By popularizing the 2% propamidine SL in small scope, which showed that the propamidine fungicide have many good characteristics, such as safety to the environment and non-target organisms, especially adapted to green-house field to protect the crop pathogen. Usage of the fungicide will benefit production of the green food. 5 The propamidine has fungicidal activity against other crop pathogens, the EC50 of inhibition to mycelium development of Glomerella cingulata, Phytophthora capsic, Exserohilum turcicum and Fusarium graminearum were 93.8338 mg/L,47.4419 mg/L,5.7726 mg/L and 16.9259 mg/L, respectively. It can transmit bi-directionally in the inner of cucumber seedling. 6 The effectiveness of propamidine on ultrastructure of Botyrtis cinerea mycelium in vivo were observed under the light microscopy and transmission electro microscopy. It has been found that propamidine could induce a series ofmarked morphological and structural alterations of the mycelium, such as swollen of part of mycelium, malforming septa, increase of the number of cell mitochondrion, the cell liquid seepage. Above cytological changes resulted in the necrosis of mycelium cell. The propamidine fungicide has obtained country registration (The propamidine registration code is LS20040092, The registration number of 2% Propamidine SL is LS20040130). It was patented in China (The application number is 02114480.X and 200410073073.X). This fungicide compound is one of few proprietary intellectual property rights in our country.