Gulonamide

Several amides of derivatives of L-gulonic acid (3) have been prepared. On treatment of 2,3 5,6-di-O-isopropylidene-L-gulono-l,4-lactone (the preparation of which is discussed in Section V) with ammonia in methanol, 2,3 5,6-di-0-isopropylidene-L-gulonamide (45) is formed.76 Similarly, 3,5-O-benzylidene-L-gulonamide (46) was prepared76 from the corresponding lactone. 

On treatment of 2,3 4,5-di-0-isopropylidene-D-xylose with cyclohexyl isonitrile and ammonium acetate, 2-acetamido-N-cyclohexyl-2-deoxy-3,4 5,6-di-0-isopropylidene-D-gulonamide was formed112 it was reported that only one isomer was produced in this reaction. 

In procedure B, a similar method was followed. D-Glucaro-1,4 6,3-dilactone (20) was reduced to L-gulono-1,4-lactone (21) which, when treated with ammonia in methanol, afforded L-gulonamide (22). Oxidation of 22 with sodium hypochlorite gave L-xylose (23), which formed osazone 19 with phenylhydrazine. Hydrolysis of 19 afforded 9. 

Figure 7.12 Crystal structures of (a) J -octyl-D-gluconamide (head-to-tail homodromic intralayer hydrogen bond cycle) and (b) bi-octyl-i>gulonamide (tail-to-tail interlayer hydrogen bonds)P...

Figure 4.2.4 Crystal structure of (a) A -octyl-D-gluconamide (monolayer) and (b) N-octyl-D-gulonamide (bilayer). Compare with zig-zag conformation in Figure 4.2.1. (From Svenson et al., 1994a,b.)...

Figure 4.2.5 Solid-state CPMAS- C-NMR spectra of (a)iV-octyl-D-gluconainide, (b)-gulonamide, (c)-D,L-gluconamide crystals, and (d) -D-gluconamide micellar fibers (see Fig. 4.5.6). The corresponding molecular conformations are given. Note Soft racemate crystallites (c) and micellar fibers (d) have the same headgroup conformation.

GIua>noIactone D-form, G-251 D-Glucononitrile, G-250 D-Glucothiono-1,5-lactam, T-I7I Glucuronic acid D-form, G-538 D-Gulonamide, G-584... 

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