Chemical Name : Desmethyl 2N-Nitroso Mirtazapine; N-Nitroso Mirtazapine EP Impurity D; 2-((R)-2-Amino-2-phenylacetamido)-2-((4S)-4-(((((2S,5R)-3,3-dimethyl-4,4-dioxido-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carbonyl)oxy)methoxy)carbonyl)-5,5-dimethyl-3-nitrosothiazolidin-2-yl)acetic acid