Fully sugar-based polyamides

Some other water-soluble fully sugar-based polyamides have also been obtained from activated hexaric acids 28 and 29 and the 1,5-diamino-2,3,4-tri-O-methyl-pentitols (37 and 38) and a series of hydrophilic polyamides (PA-nSu) derived from these hexaric acids and noncarbohydrate alkylenediamines with even numbers of methylenes n = 4, 6, 8, 10, 12) has also been prepared [80]. 

Garcfa-Martfn et al. reported [98] on the AABB polyamides based on these pentaric acids. Two different types of polycondensate were prepared fully sugar-based polyamides (PA-ArAr and PA-XyXy), and polyamides derived from aldaric acids and aliphatic diamines (PA- Ar and PA- Xy, = 6, 8, 12). In all these cases, aregic polymers were formed, since both sugar configurations lack the C2 axis. 

Tetra-O-methyl-D-mannaric and galactaric acids and their bis(pentachlorophenyl) esters have been prepared [99] as crystalline compounds, in good yields, from D-mannitol and galactitol, respectively. A new stereoregular fully sugar-based polyamide, analogous to Nylon 66, has also been prepared [99] by polycondensation of bis(pentachlorophenyl) 2,3,4,5-tetra-O-methyl-D-mannarate with l,6-diamino-l,6-dideoxy-2,3,4,5-tetra-<9-methyl-D-mannitol dihydrochloride [100]. 

Some other fully sugar-based polyamides have been obtained from these activated hexaric acids and the 1,5-diamino-2,3,4-tri-(9-methyl-pentitols having the L-arabino andxyto configuration [101]. 

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