PNA bearing 5-azidomethyluracil

Abstract

Fmoc- and Boc-protected modified monomers bearing 5-azidomethyluracil nucleobase were synthesized. Four different solid-phase synthetic strategies were tested in order to evaluate the application of this series of monomers for the solid-phase synthesis of modified PNA. The azide was used as masked amine for the introduction of amide-linked functional groups, allowing the production of a library of compounds starting from a single modified monomer. The azide function was also exploited as reactive group for the modification of PNA in solution via azide-alkyne click cycloaddition.

Pyrene-modified PNAs: Stacking interactions and selective excimer emission in PNA2DNA triplexes

“…The probe containing only 1 pyrene unit ( PNA1 , Fig. 1 ) was synthesized by on-resin modification of 5-azidomethyluracil precursor, as described previously [ 35 ], whereas a pyrene-containing modified monomer 1 ( Scheme 1 ), more suitable for automated synthesis, was designed for the realization of all the other oligomers ( PNA2 – 6, Fig. 1 ).…”

“…For the synthesis of the modified monomer bearing the pyrene moiety, we started from the 5-azidomethyluracil building block 2 previously synthesized by our lab [ 35 ]. The azide function was first reduced under Staudinger conditions to the corresponding amine 3 , on which 1-pyreneacetic acid was linked using HBTU/DIPEA as condensing agent.…”

“…We have recently reported the modification of uracil at C5 by hydroxymethylation, followed by substitution with chloride and then with azide, which can be used for click chemistry or as a masked amino group both in a PNA monomer and in PNA oligomers, allowing to produce a variety of modified PNAs from a single precursor [ 35 ]. This chemistry introduces a moderate degree of flexibility which can be useful for allowing interactions with other groups to occur within the major groove.…”

Synthesis and Improved Cross-Linking Properties of C5-Modified Furan Bearing PNAs

“…First, 2-((5-azidomethyl)uracil-1-yl)acetic acid [ 52 ] and 3-(2-furyl)propionic acid [ 47 ] were synthesized accordingly to previously reported procedures. The synthesis of PNA 1 , PNA 4 , and PNA 7 was reported earlier [ 47 ].…”

Novel nicotinoid structures for covalent modification of wood: an environmentally friendly way for its protection against insects

“…In order to attach the linker moieties 7-11 to imidacloprid (1), nucleophilic substitution reactions were carried out applying sodium hydride in dry DMF (Scheme 4), following a modied procedure from Kagabu et al 32 The substitution products 7a-11a have been isolated in good yields ( Table 1). The ester groups were subsequently hydrolysed using triuoroacetic acid in DCM according to Manicardi et al 33,34 The almost quantitatively obtained carboxylic acids 7b-11b were then activated with thionyl chloride and 1H-benzotriazole (Scheme 4). This reaction process, in which the carboxylic acid chloride rst forms and then reacts in situ to the activated benzotriazolate, was developed by Katritzky.…”