Nitro-benzamide useful as anti-arrhythmic agent

N-[3-[[2-hydrate (3,4-methyl phenyl) ethyl] amino] propyl]-phenyl benzamide hydrochloride is characterized by: (I) contains 1.7-2.4 molar equivalents of water, (ii) melting point greater than 145 degrees centigrade, and/or (iii) infrared peak of spectrum, including 3510,3342,3076,1665,1598,1343,1330,1216 and 801cm-1, (iv) Provide solid state nuclear magnetic resonance chemical shifts of specific table ⅰ; and/or (v) x-ray powder diffraction (XRPD) patterns in the data indicated in table II. Method of preparation of the compounds, containing medicinal composition for this compound, as well as the use of drugs in medicine.