1-(4-(Hexahydro-1H-azepin-1-yl)-2-butynyl)-2-pyrrolidinone fumarate (2:3) 18900-05-5 2-Pyrrolidinone, 1-(4-(hexahydro-1H-azepin-1-yl)-2-butynyl)-, fumarate (2:3) PN 309