7-DEAZAPURIN-2,6-DIAMINE AND 7-DEAZAGUANINE: SYNTHESIS AND PROPERTY OF 7-SUBSTITUTED NUCLEOSIDES AND OLIGONUCLEOTIDES
摘要:
The synthesis of 7-substituted 7-deazaguanine and 7-deazaadenine ribonucleosides 1-2, the incorporation of 3a-d into oligonucleotides, and the stability of the corresponding duplexes and base discrimination are described. The pK(a), values of 3 - 4 are determined.
7-Functionalized 7-Deazapurine Ribonucleosides Related to 2-Aminoadenosine, Guanosine, and Xanthosine: Glycosylation of Pyrrolo[2,3-d]pyrimidines with 1-O-Acetyl-2,3,5-tri-O-benzoyl-d-ribofuranose
摘要:
The Silyl-Hilbert-Johnson reaction as well as the nucleobase-anion glycosylation of a series of 7-deazapurines has been investigated, and the 7-functionalized 7-deazapurine ribonucleosides were prepared. Glycosylation of the 7-halogenated 6-chloro-2-pivaloylamino-7-deazapurines 9b-d with 1-O-acetyl2,3,5-tri-O-benzOyl-D-ribofuranose (5) gave the beta-D-nucleosides 11b-d (73-75% yield), which were transformed to a number of novel 7-halogenated 7-deazapurine ribonucleosides (2b-d, 3b-d, and 4b-d) related to guanosine, 2-aminoadenosine, and xanthosine. 7-Alkynyl derivatives (2e-i, 3e-h, or 4g) have been prepared from the corresponding 7-iodonucleosides 2d, 3d, or 4d employing the palladium-catalyzed Sonogashira cross-coupling reaction. The 7-halogenated 2-amino-7-deazapurine ribonucleosides with a reactive 6-chloro substituent (18b-d) were synthesized in an alternative way using nucleobase-anion glycosylation performed on the 7-halogenated 2-arnino-6-chloro-7-deazapurines 13b-d with 5-0-[(1,1dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-alpha-D-ribofuranosyl chloride (17). Compounds 18b-d have been converted to the nucleosides 19b-d carrying reactive substituents in the pyrimidine moiety. Conformational analysis of selected nucleosides on the basis of proton coupling constants and using the program PSEUROT showed that these ribonucleosides exist in a preferred S conformation in solution.
C6–O-alkylated 7-deazainosine nucleoside analogues: Discovery of potent and selective anti-sleeping sickness agents
作者:Fabian Hulpia、Jakob Bouton、Gustavo D. Campagnaro、Ibrahim A. Alfayez、Dorien Mabille、Louis Maes、Harry P. de Koning、Guy Caljon、Serge Van Calenbergh
DOI:10.1016/j.ejmech.2019.112018
日期:2020.2
, is spread to new hosts by bites of infected tsetse flies. Currently approved therapies all have their specific drawbacks, prompting a search for novel therapeutic agents. T. brucei lacks the enzymes necessary to forge the purine ring from amino acid precursors, rendering them dependent on the uptake and interconversion of host purines. This dependency renders analogues of purines and corresponding