Synthesis and mass spectra of the partially methylated and partially ethylated anhydro-D-mannitol acetates derived by reductive cleavage of permethylated and perethylated Saccharomyces cerevisiae D-mannans.

Reductive cleavage of per-O-ethylated or per-O-methylated Saccharomyces cerevisiae D-mannans and subsequent acetylation had previously been shown to produce the expected derivatives of 1,5-anhydro-D-mannitol. Described herein is the independent synthesis of each of these derivatives, namely, 1,5-anhydro-2,3,4,6-tetra-O-methyl-, -2,3,4,6-tetra-O-ethyl-, -2-O-acetyl-3,4,6-tri-O-methyl-, -2-O-acetyl-3,4,6-tri-O-ethyl-, -3-O-acetyl-2,4,6-tri-O-methyl-, -3-O-acetyl-2,4,6-tri-O-ethyl-, -6-O-acetyl-2,3,4-tri-O-methyl-, -6-O-acetyl-2,3,4-tri-O-ethyl-, -2,6-di-O-acetyl-3,4-di-O-methyl-, -2,6-di-O-acetyl-3,4-di-O-ethyl-, -3,6-di-O-acetyl-2,4-di-O-methyl-, and -3,6-di-O-acetyl-2,4-di-O-ethyl-D-mannitol. The 1H-n.m.r. spectra, chemical-ionization (NH3) mass spectra, and electron-impact mass spectra for all of these derivatives are tabulated.