Unprecedented dinuclear silver(<scp>i</scp>)-mediated base pair involving the DNA lesion 1,N<sup>6</sup>-ethenoadenine
作者:Soham Mandal、Alexander Hepp、Jens Müller
DOI:10.1039/c4dt02663b
日期:——
For the first time, a dinuclear purine-based metal-mediated homo base pair has been incorporated into a B-DNA duplex.
这是翻译结果:
首次将双核嘌呤基金属介导的同源碱基对合并到B-DNA双链中。
Metal-Mediated Assembly of 1,<i>N</i><sup>6</sup>-Ethenoadenine: From Surfaces to DNA Duplexes
作者:Soham Mandal、Can Wang、Rajneesh K. Prajapati、Jutta Kösters、Sandeep Verma、Lifeng Chi、Jens Müller
DOI:10.1021/acs.inorgchem.6b00927
日期:2016.7.18
ligands bind to Ag(I) ions. The molecular structures of [Ag2(1)2](ClO4)2 and [Ag2(2)2](ClO4)2 (1, 9-ethyl-1,N6-ethenoadenine; 2, 9-propyl-1,N6-propylenoadenine) confirm that dinuclear complexes with short Ag···Ag distances are formed (3.0256(3) and 2.984(1) Å, respectively). The structural motif can be extended to divalent metal ions, as was shown by determining the molecular structure of [Cu2(1)2(CHO2)2(OH2)2](NO3)2·2H2O
Treatment of 9-ethy-1-(2-hydroxythyl)adenide hydrobromide (1a) in boiling N, N-dimethylformamide (DMF) with an excess of thiourea for 7 h or with an excess of ammonium thiocyanate for 3 h provided 3-ethyl-7, 8-dihydro-3H-imidazo[2, 1-i]purinium thiocyanate (8) in 51% or 58% yield, respectively. On treatment with an excess of triphenyl phosphite in boiling DMF for 20 min, 1 a underwent a similar cyclization to from the same tricycle, which was isolated in 81% yield (from 1 a)in the form of the perchlorate salt (12). A similar treatment of 1 a with triethyl phosphite furnished the 9-ethyl analogue (15) in 83% yield. Conversion of 12 into the free base and oxidation of latter with active MnO2 in boiling CH2Cl2 for 16 h gave 3-ethyl 3-ethyl-3H-imidazo[2, 1-i]purine (13) (66% overall yield from 12), which was identical with a sample synthesized from 9-ethyladenine (9) and chloroacetaldehyde according to the general N6, 1-etheno bridgeing procedure. On treatment with methanolic ammonia at room temperature, the tricycle 15 afforded 9-ethyl-N6-[2-(ethylamino)ethyl]adenine hydrobromide (26) in 79% yield. Mechanisms are proposed for the above intramolecular cyclizations of 1 a caused by the S- and P-atom nucleophiles.