Synthesis and Antifungal Activity of Some New Fluorine-Substituted 4-Thiazolidinone Bearing 1 , 2 , 4-Triazinone

Fluorine substituted 4-thiazolidinone 5 bearing 1,2,4-triazinone obtained from the condensation of 3-Amino-6(2’-aminophenyl)-1,2,4-triazin-5(4H)-one (2) with an aromatic aldehyde followed by cycloaddition with mercaptoacetic acid afforded the thiazolidinone (4), and treatment with ethyl trifluoroacetate. Structure of the products has been deduced from their correct elemental analysis and spectral measurements. The antifungal activity of the new fluorinated target also has been evaluated.


Introduction
The use of heterocycles as chemical fertilizers to increase the yield of crops and to eliminate all kinds of parasites able to attack the cultivation is becoming more important because of the great problem facing the world to provide food to an increasing population [1].Among these heterocycles, (2-thioxo-thiazolidin-4-one) and its derivatives exhibit a wide spectrum in the medicinal, pharmacological and agricultural [2], as well as use for determination of Cu(II), Hg(II), Cl − and CN − ions in the industrial wastewater [3].On the other hand, functionally 1,2,4-triazine derivatives have essential properties as medicinal, pharmacological and biological fields [4] [5] [6].Also, the introduction of fluorine atom to the heterocyclic systems often enhances and improves their properties [7]

Antifungal Evaluation
Firstly, in vitro, the newly prepared compounds were assayed against the growth of some phytopathogenic fungi associated with what grains, i.e.Fusarium moniliforme ED 50 values determined by regression analysis of the long probit transformed data [11] [12].From the result obtained show that compounds 5 and 4 are the most effective against the tested fungi.A higher effect of these compounds is may be due to containing fluorine atoms and/or 4-thiazolidinone moiety (Table 1).
Secondly, in vivo, the compound 5 has highest protecting activity on the grains (Tritium aestivum C.V Giza lss) of wheat against the fungal infection and increases the wheat germination compared with untreated grains.The best control of the used fungi achieved by 1000 mg/ml of compound 4 (704.Germination).

Conclusion
The fluorine substituted 4-thiazolidinone bearing 1,2,4-triazinone synthesized and compared with non-fluorinated were the fluorinated systems 5 exhibits highest germination (more plant protection) than the non-fluorinated systems 4 (lower plant protection).
.25) International Journal of Organic Chemistry . The assay performed by incorporating the tested compounds with nu- trient agar at different concentration.The compounds dissolved in DMF and distilled water.The poisoned media were poured into sterile Petri-dishes and allowed to solidify.Each dish inoculated with a 4 mm diameter disk of inoculum removed from a 7 day old culture of the tested pathogens.Other media supplemented with DMF serving as a control.Treatment replicated 3 times, and the plates incubated at 27˚C.Growth on the compound amended media determined by men swing colony diameter (cm) and growth inhibition calculated with reference to the control.