A molecular receptor selective for zwitterionic alanine

作者:Rubio Omayra H; Taouil Rachid; Muniz Francisco M*; Monleon Laura M; Simon Luis; Sanz Francisca; Moran Joaquin R
来源:Organic and Biomolecular Chemistry, 2017, 15(2): 477-485.
DOI:10.1039/c6ob02237e

摘要

A molecular receptor has been synthesized joining an aza-crown ether with a chiral chromane which mimics the oxyanion hole of the enzymes. With this receptor an apolar host-guest complex with zwitter-ionic alanine has been achieved through the formation of up to seven H-bonds. This complex allows the extraction of aqueous alanine to a chloroform phase, while other natural amino acids are poorly extracted or are not extracted at all. Due to the chiral nature of the receptor, enantioselective extraction from the aqueous alanine solution to a chloroform phase takes place. X-Ray analysis combined with anisotropic effects, NOE and CD studies revealed the absolute configuration of both strong and weak complexes. Modelling studies also support the proposed structures. The presence of an oxyanion-hole motif in this structure was corroborated by X-ray diffraction studies.

  • 出版日期2017-1-14