Description Quasi-orthogonally-protected Lys derivative. The Fmoc group can be removed selectively by treatment with piperidine; the Dde group is cleaved with 2% hydrazine in DMF [1]. When removing Dde in the presence of allyl based protecting groups, allyl alcohol should be included in the deprotection solution to prevent reduction of the allyl group [2].Lys(Dde) has been employed in the following applications: synthesis of branched peptides [1] and di-epitopic peptides [3]; preparation of MAP core molecules and lipo-MAPs [4, 5]; construction of cyclic peptides [6], TASP molecules [7], templates for combinatorial chemistry [8] and synthetic proteins [9]; preparation of peptides modified at the lysine side-chain [10-14].It has been reported that Dde can migrate from the side-chain of Lys to the unprotected side-chain of another Lys residue [15], and from the β-amino group to the α-amino group of Dpr [16]. In the former instance, this problem can be overcome by using Fmoc-Lys(ivDde)-OH (852082) or using DBU/DMF (2:98) for Fmoc group removal [15, 17].Full orthogonality of Dde with Fmoc has recently been demonstrated when hydroxylamine is used for Dde removal [18].The product number for this product was previously 04-13-1028..