Synthesis of haptens and their protein conjugates for immunological determination of nitrate esters and nitramines

Isosteric, isopolar analogues of the nitrate ester pentaerythritol tetranitrate (PETN) and of the cyclic nitramine sym-cyclotrimethylene trinitramine (RDX) having a spacer arm have been linked to carrier proteins to provide immunologically active peptide conjugates. X-Ray structures of RDX, RDX analogue 10, and hapten 14 are compared to establish their conformational relationships.