Étude conformationnelle et structurale de 1,5-diacétoxy-3,4-bis(bicyclophosphoranylato)quinate de méthyle

Abstract

In connection with our work on quinic acid derivatives, which are supposed to regulate the biosynthesis of aromatic amino acids, we have prepared the methyl 1,5-di-O-acetyl-3,4-bis-O-(bicyclophosphoranylato)quinate 7. The compound obtained has been characterized by NMR (1H and 31P), IR, elemental analysis, and mass spectrometry. Its molecular structure has been determined by X-ray diffraction and an exhaustive conformational study has been accomplished. The quinic ring adopts an almost perfect chair form. Both bicyclophosphoranyl groups present a trigonal bipyramidal geometry with an axial–equatorial–axial type annelation. The pentagonal rings adopt an envelope form in which the tetrasubstituted carbon atom is at the top of the fold. Key words: shikimic acid pathway, methyl 1,5-di-O-acetyl-3,4-bis-O-(bicyclophosphoranylato)quinate, conformational analysis, 1H and 31PNMR, crystal structure.