1-Cyclohexyl-2-pyrrolidinone 2-Pyrrolidinone, 1-cyclohexyl- 5-21-06-00331 (Beilstein Handbook Reference) 6837-24-7 BRN 0121832 Cyclohexyl pyrrolidone EINECS 229-919-7 N-Cyclohexyl-2-pyrrolidone N-Cyclohexylpyrrolidinone N-Cyclohexylpyrrolidone