| SMILES = NC(NN)=O }} | Section2 = }} In organic chemistry, semicarbazide's a derivative of urea, where NH2 on one side has been replaced with H2NNH2 hydrazine, yielding H2NNHC(=O)NH2. Semicarbazide's used as a detection reagent on thin layer chromatography (TLC). Semicarbazide stains α-keto acids on the TLC plate, which must then be viewed under a UV light to see the results. A thiosemicarbazide's an analog with a sulfur atom in place of the oxygen atom. Image:Urea.png|Urea Image:Hydraz… (More on Semicarbazide)