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Conformation of repaglinide: a solvent dependent structure

Chashmniam, S ; Sharif University of Technology

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  1. Type of Document: Article
  2. DOI: 10.1016/j.molstruc.2017.04.097
  3. Abstract:
  4. Experimental and theoretical conformational study of repaglinide in chloroform and dimethyl sulfoxide was investigated. By applying potential energy scanning (PES) at B3LYP/6-311++g** and B3LYP-D3/6-311++g** level of theory on rotatable single bonds, four stable conformers (R1-R4) were identified. Spin-spin coupling constant values were obtained from a set of 2D NMR spectra (H[sbnd]H COSY, H[sbnd]C HMQC and H[sbnd]C HMBC) and compared to its calculated values. Interestingly, from 1HNMR and 2D-NOESY NMR, it has been found that repaglinide structure is folded in CDCl3 and cause all single bonds to rotate at an extremely slow rate. On the other hand, in DMSO-d6, with strong solvent-solute intermolecular interactions, the single bonds rotate freely. Also, energy barrier and thermodynamic parameters for chair to chair interconversion was measured (13.04 kcal mol−1) in CDCl3 solvent by using temperature dynamic NMR. © 2017 Elsevier B.V
  5. Keywords:
  6. Advanced 2D-NMR ; Conformation ; DFT ; Repaglinide ; Conformations ; Dimethyl sulfoxide ; Organic solvents ; Potential energy ; Solvents ; 2-D NMR ; Calculated values ; Conformational study ; Intermolecular interactions ; Spin-spin coupling constants ; Temperature dynamics ; Thermodynamic parameter ; Nuclear magnetic resonance spectroscopy
  7. Source: Journal of Molecular Structure ; Volume 1143 , 2017 , Pages 388-396 ; 00222860 (ISSN)
  8. URL: https://www.sciencedirect.com/science/article/abs/pii/S0022286017305513