Abstract: Studies on the Mass Spectra of Some New Arylthiosemicarbazide Compounds(Ⅰ)Zhang Qingzhi;Hua Guoxiong;Wang Hong;Wang Yulu; Ma Donglan;Zhang Shenshong (Department of Chemistry, Henan Normal University, Xinxiang 453002,China) (Xinxiang Huangu Chemical Co,Xinxiang 453003, China)Abstract:Electron impact mass spectra (EIMS) of eight new arylthiosemicarbazide compounds, 1-(2-carboxyl phenyl)-4-alkyl thiosemicarbazides, were reported. It was found that all the mass spectra showed high relative intensity of molecular ions (M~+). The fragmentation pattern of molecular ions was dominated by the dissociation of N - N bond and C-N bond, together with either six-centred or four-centred transition state of hydrogen rearrangement. The resultant fragment ions continued further losses of water or other low molecules, giving arise of a series of characteristic ions, including that of skeletal rearrangement. The mass spectra were slightly influenced by N-substituent R. Keywords: EIMS, hydrogen rearrangement, skeletal rearrangement, arylthiosemicarbazide compounds