The development and preparation of the 2,4-dimethoxybenzyl arylhydrazine (DMBAH) “latent” safety-catch linker: solid phase synthesis of ketopiperazines
The development and preparation of the 2,4-dimethoxybenzyl arylhydrazine (DMBAH) “latent” safety-catch linker: solid phase synthesis of ketopiperazines
Solid-Phase Synthesis, Hybridizing Ability, Uptake, and Nuclease Resistant Profiles of Position-Selective Cationic and Hydrophobic Phosphotriester Oligonucleotides
作者:Luca Monfregola、Marvin H. Caruthers
DOI:10.1021/acs.joc.5b01512
日期:2015.9.18
Analogues of oligonucleotides and mononucleotides with hydrophobic and/or cationic phophotriester functionalities often generate an improvement in target affinity and cellular uptake. Here we report the synthesis of phosphotriester oligodeoxyribonucleotides (ODNs) that are stable to the conditions used for their preparation. The method has been demonstrated by introducing phosphoramidite synthons where N-benzyloxycarbonyl (Z) protected amino alcohols replace the cyanoethyl group. After synthesis these ODNs were found to be stable to the condition required to remove base labile protecting groups and the ODNs from the solid support. Moreover the use of 1-(4,4-dimethyl-2, 6-dioxocyclohex-1-ylidene) ethyl (Dde) in place of Z protection on the amino alcohol has allowed us to introduce cationic aminoethyl phosphotriester modifications into ODNs. Melting temperatures of duplexes containing cationic or hydrophobic Z modified ODNs indicate that the backbone-phosphotriester modifications minimally affect duplex stability. Nuclease stability assays demonstrate that these phosphotriesters are resistant toward 5'- and 3'-exonudeases. Fluorescently labeled 23-mer ODNs modified with four cationic or hydrophobic Z phosphotriester linkages show efficient cellular uptake during passive transfection in HeLa and Jurkat cells.
The synthesis of cyclic tetrapeptoid analogues of the antiprotozoal natural product apicidin
作者:Peter J Murray、Michael Kranz、Mark Ladlow、Stephen Taylor、Frédéric Berst、Andrew B Holmes、Kenneth N Keavey、Albert Jaxa-Chamiec、Peter W Seale、Paul Stead、Richard J Upton、Simon L Croft、William Clegg、Mark R.J Elsegood
DOI:10.1016/s0960-894x(01)00049-x
日期:2001.3
A novel synthetic strategy is described which may be used to prepare analogues of the antimalarial, fungal metabolite apicidin. Compared to the natural product, one analogue shows potent and selective activity in vitro against the parasite Trypanosoma brucei and low mammalian cell toxicity. (C) 2001 Elsevier Science Ltd. All rights reserved.
A latent aryl hydrazine ‘safety-catch’ linker compatible with N-alkylation
作者:Frédéric Berst、Andrew B Holmes、Mark Ladlow、Peter John Murray
DOI:10.1016/s0040-4039(00)01108-4
日期:2000.8
The preparation and use of a latent aryl hydrazine 'safety-catch' linker for solid-phase chemistry, which is compatible with N-alkylation, is reported. Its use is exemplified by the preparation of mono-ketopiperazines, whereby release from resin is effected via an intramolecular cyclitive cleavage strategy. (C) 2000 Elsevier Science Ltd, All rights reserved.
The development and preparation of the 2,4-dimethoxybenzyl arylhydrazine (DMBAH) “latent” safety-catch linker: solid phase synthesis of ketopiperazines
作者:Frédéric Berst、Andrew B. Holmes、Mark Ladlow
DOI:10.1039/b301701j
日期:——
The development and preparation of the 2,4-dimethoxybenzyl arylhydrazine (DMBAH) linker 3, a new class of âlatentâ safety-catch linker which is stable under Mitsunobu alkylation conditions and in the presence of amines and hydrazine, is reported. The utility of the new linker is exemplified by the synthesis of ketopiperazines (MKPs)
24 bearing up to four points of diversity using a cyclitive cleavage approach.