Folded conformations due to arene interactions in dissymmetric and symmetric butylidene-linker models based on pyrazolo[3,4-<i>d</i>]pyrimidine, purine and 7-deazapurine
作者:Kamlakar Avasthi、Lakshmi Shukla、Ruchir Kant、Krishnan Ravikumar
DOI:10.1107/s2053229614009449
日期:2014.6.15
models 1‐[2‐(2,6‐dimethylsulfanyl‐9H‐purin‐9‐yl)‐2‐methylidenepropyl]‐4,6‐bis(methylsulfanyl)‐1H‐pyrazolo[3,4‐d]pyrimidine, C18H20N8S4, (XI), 7,7′‐(2‐methylidenepropane‐1,3‐diyl)bis[3‐methyl‐2‐methylsulfanyl‐3H‐pyrrolo[2,3‐d]pyrimidin‐4(7H)‐one], C20H22N6O2S2, (XIV), and 7‐[2‐(4,6‐dimethylsulfanyl‐1H‐pyrazolo[3,4‐d]pyrimidin‐1‐yl)‐2‐methylidenepropyl]‐3‐methyl‐2‐methylsulfanyl‐3H‐pyrrolo[2,3‐d]pyrimidin‐4(7H)‐one
丁叉接头模型1 [[2-(2,6-二甲基硫烷基-9 H-嘌呤-9-9基)-2-亚甲基丙基] -4,6-双(甲基硫烷基)-1 H-吡唑并[3,4- d ]嘧啶,C 18 H 20 N 8 S 4,(XI),7,7'-(2-亚甲基丙烷-1,3-二基)双[3-甲基-2-甲基硫基-3 H-吡咯并[2, 3 - d ]嘧啶-4(7 H)-1 ],C 20 H 22 N 6 O 2 S 2,(XIV)和7- [2-(4,6-二甲基硫烷基-1 H-吡唑并[3, 4 - d ]嘧啶-1-基)-2-亚甲基丙基] -3-甲基-2-甲基硫烷基-3H-吡咯并[2,3 - d ]嘧啶-4(7 H)-one,C 19 H 21 N 7 OS 3(XV)在溶液中显示折叠构象,如1 H NMR分析所示。这种折叠会延续到结晶状态。在所有三种化合物中均观察到分子内π-π相互作用,但只有(XIV)在固态下显示出额外的分子内CH-H