1,6-Diamino-2,5-anhydro-1,6-dideoxy-dl-glucitol and some derivatives thereof

1,6-Diamino-2,5-anhydro-1,6-dideoxy-dl-glucitol dihydrochloride and some derivatives were synthesized from 3,5-di-O-acetyl-1,6-dibromo-1,6-dideoxy-d-mannitol. Introduction of the 2,5-anhydro ring and subsequent replacement of the terminal bromine atoms by azide gave low yields of the diazide; therefore, a reverse reaction-sequence was applied. The azido groups were reduced with hydrogen sulfide-pyridine, and the amino groups formed were methylated by using formaldehyde-formic acid and subsequently treating with borohydride. According to ¹³C-n.m.r. investigations, the symmetrically substituted, 2,5-anhydroglucitol derivatives are present mainly in the ⁴T₃ “north” (N) type of twist] conformation, whereas the analogous l-iditol derivatives mainly adopt the ³T₄ “south” (S)] type. The different quaternary salts obtained on methylation of the corresponding 1,6-bis(dimethylamino)derivatives with methyl iodide (aiming at the structure of epi-muscarine) showed no muscarine-like, biological activity.