The Position of Phosphate Groups in the Phosphonomannan of Hansenula capsulata, as Determined by Carbon-13 Magnetic Resonance Spectroscopy

Abstract

The carbon-13 magnetic resonance spectrum of a phosphate of 2-O-β-D-mannopyranosyl-α,β-D-mannose was compared with that of the unphosphorylated disaccharide. The positions and number of the signals of C-5's which are coupled to phosphorus-31, together with other spectral data show that the phosphate group is on C-6 of the reducing end-unit (2, Fig. 1). This differs from a previous assignment (1), thus necessitating a revision (4) to the structure 3 proposed for the parent Hansenula capsulata phosphonomannan.