Solid-phase synthesis of acid-sensitive N-(2-aminoethyl)glycine-PNA oligomers by the Fmoc/Bhoc strategy

In the context of investigation of nucleic acid-mediated excess electron transfer, a bis-functionalized (2-aminoethyl)glycine-PNA modified with a flavin and an oxetane moiety was synthesized. The solid-phase synthesis of the required PNA oligomer was especially intriguing because of the high acid sensitivity of the oxetane moiety, so the Fmoc/Bhoc strategy was adapted to the mild cleavage conditions of the Sieberamide resin. Along with smooth oligomerization conditions, the syntheses of oxetane- and flavin-functionalized Fmoc-protected (2-aminoethyl)glycine building blocks are reported. (C) Wiley-VCH Verlag GmbH & Co.