Asked | Open questions | Answered Points Date Pair Term / Answer given Level Status Gloss 2 Apr 7 '04 nor>eng piperazinring piperazine ring pro closed no 2 Apr 7 '04 nor>eng pyrimidinring pyrimidine ring pro closed ok - Apr 7 '04 nor>eng pyrimidinring pyrimide ring pro closed ok Asked | Open questions | Answered