Synthesis of New Coumarin Derivatives Used as Nitrification Inhibitors to Mitigation of Nitrous Oxide Emission from Agricultural Soil.

Nitrous oxide (N2O) is one of the major greenhouse gases "GHG” the main source of N2O emission is synthetic mineral nitrogen fertilizers. The conversion values according to the global warming potential for N2O are 298 times as CO2 per molecule. The main objective of this work is to mitigate GHG emission from N2O by create synthesis new nitrification inhibitors.  Coumarine derivatives were synthesized (1-4), and prove the structures by spectral data, the compounds (1) and (4) were applied as nitrification inhibitors to mitigation of nitrous oxide. The results indicated that, the presence of each of the two tested inhibitors (1, 4) reduced the N2O emission from urea-treated soils by 72% and 49%, respectively, in inhibiting nitrification during the 28-day incubation period. Key words: Nitrous oxide emissions, Mitigation, Agricultural soil, Nitrification, Coumarin derivatives