One kind of novel chiral porphyrin and its zinc complex were synthesized and characterized. The molecular recognition of chiral zinc porphyrin towards amino acid esters in CHCl3 was investigated by UV‐vis spectral titration method. The associative constants of the molecular recognition reactions were all KD>KL and followed the order of K(PheOMe)>K(LeuOMe)>K(ValOMe)>K(AlaOMe) in host (Zn(L‐BocTyr)TAPP). Circular dichroism spectra were used to explain chiral molecular recognition. The minimal energy conformation of host‐guest molecular system was sought by molecular dynamics method. The molecular recognition process of this host‐guest system was calculated by quantum chemistry and the results were explained by the experiments 相似文献
Molecularly imprinted polymeric membranes were prepared from polystyrene resin bearing tetrapeptide derivatives H‐Asp(OcHex)‐Leu‐Asp(OcHex)‐Glu(OBzl)‐OCH2‐ (DLDE) consisting of D ‐amino acid residues or L ‐amino acid residues. The tetrapeptide derivatives were converted into chiral recognition sites by using not only an optically pure Boc‐Trp but also racemic Boc‐Trps as a print molecule. The chiral recognition ability depends on the combination of the absolute configuration of the print molecule and that of constituting amino acid residues. The membrane prepared from a DLDE derivative consisting of D ‐amino acid residues and imprinted by Boc‐D ‐Trp recognized the D ‐isomer in preference to the corresponding L ‐isomer and vice versa. In the present study, it was also made clear that racemic print molecules were effective in generating chiral recognition sites. The affinity constant of the generated chiral recognition site was determined to be 9.6 × 103 mol?1 · dm3, which was independent of the molecular imprinting conditions. Enantioselective permeation was attained by applying electrodialysis. An optimum permselectivity of 5.9, which corresponds to the adsorption selectivity, was attained.
Summary of the molecularly imprinted polymeric membranes studied. 相似文献
Molecular dynamics simulations were used to characterize the binding of the chiral drugs chlorthalidone and lorazepam to the molecular micelle poly-(sodium undecyl-(L)-leucine-valine). The project’s goal was to characterize the nature of chiral recognition in capillary electrophoresis separations that use molecular micelles as the chiral selector. The shapes and charge distributions of the chiral molecules investigated, their orientations within the molecular micelle chiral binding pockets, and the formation of stereoselective intermolecular hydrogen bonds with the molecular micelle were all found to play key roles in determining where and how lorazepam and chlorthalidone enantiomers interacted with the molecular micelle. 相似文献
