1-(2-Oxoazepane-1-carbonyl)azepan-2-one19494-73-631 % similar Dithiodicaprolactam23847-08-731 % similar N1,N1,N6,N6-Tetrakis(2-hydroxyethyl)hexanediamide6334-25-431 % similar 4-(2-Oxo-1-pyrrolidinyl)benzaldehyde36151-45-831 % similar Piracetam7491-74-931 % similar 1-Benzyl-3-pyrrolidone5291-77-030 % similar Methyl 2-oxo-1-pyrrolidineacetate59776-88-430 % similar