AlMotriptan Related CoMpound B

5-??[(1-??Pyrrolidinylsulfonyl??)??Methyl]??-??1H-??Indole-??3-??Ethanamine (2E)??-??2-??Butenedioate used in the preparation of almotriptan and its salts by cyclocondensation of chlorobutyraldehyde acetal with (hydrazinylbenzylsulfonyl)pyrrolidine.