Fine tuning of folded conformation by change of substituents:: 1H NMR and crystallographic evidence for folded conformation due to arene interactions in pyrazolo[3,4-d]pyrimidine core based 'propylene linker' compounds

被引：16

作者：

Avasthi, K ^{[1
]}

Aswal, S

Kumar, R

Yadav, U

Rawat, DS

Maulik, PR

机构：

[1] Cent Drug Res Inst, Div Med & Proc Chem, Lucknow 226001, Uttar Pradesh, India

[2] Cent Drug Res Inst, Mol & Struct Biol Div, Lucknow 226001, Uttar Pradesh, India

来源：

JOURNAL OF MOLECULAR STRUCTURE | 2005年 / 750卷 / 1-3期

关键词：

H-1 NMR spectroscopy; X-ray crystallography; stacking interactions; conformation;

D O I：

10.1016/j.molstruc.2005.04.033

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Proton NMR and X-ray crystallographic analysis of two newly synthesized 'trimethylene linker,' (Leonard linker) compounds 1,3-bis(4-ethoxy-6-methylsulfanyl-1H-pyrazolo [3,4-d]pyrimidin-1-yl)propane (4c) and 1,3-bis(4-isopropoxy-6-methylsulfanyl-1H-pyrazolo[3,4d]pyrimidin-1-yl)propane (4d) show intramolecularly stacked conformations both in solution and solid state. Robustness of the unusual U-motif formed due to intramolecular stacking in earlier related compounds (1, n = 3 and 3, n = 3) is not only confirmed but additional fine tuning is also achieved in new compounds (4) formed by replacement of remote 4-alkylsulfanyl group in la by 4-alkoxy substituents. (c) 2005 Elsevier B.V. All rights reserved.

引用

页码：179 / 185

页数：7

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