The shikimate pathway. Part 8. Synthesis of (−)-3(R)-amino-4(R),5(R)-dihydroxy-1-cyclohexene-1-carboxylic acid: The 3(R)-amino analogue of (−)-shikimic acid

Novel Lipid‐Peroxidation‐ and Cyclooxygenase‐Inhibitory Tannins from Picrorhiza kurroa Seeds

“…The downfield shifts of the sugar HÀC(1), HÀC(2), and HÀC (4) Further purification of fraction A by RP-MPLC (C 18 ; MeOH/H 2 O) yielded compounds 5 and 6 as colorless needles. The [a] D value of 5 was À 168, and further spectral studies confirmed it as (À)-shikimic acid [20]. Similarly, compound 6 was identified as gallic acid [21].…”

Synthesis of (6S)-6-hydroxy-4-epi-shikimic acid

“…Shikimic acid was obtained by extraction from Chinese star anise following ref. 19. Substrate 7 was synthesized from shikimic acid by a literature procedure.…”

Total quantification and extraction of shikimic acid from star anise (llicium verum) using solid-state NMR and cellulose-dissolving aqueous hydroxide solutions

“…5-8 wt % shikimic acid from star anise). [36,38,56] A recovery of only 6.6 ± 0.1 wt % shikimic acid, relative to the quantity determined and ca. 9 wt % cellulose for tetrabutylammonium ([N 4444 ] + ) hydroxide.…”

“…10.8 wt % of the initial mass was isolated as a shikimic acid-rich crude phase. This crude was then subjected to ion exchange purification [38,56] by loading upon a hydroxide-loaded anion exchange membrane, washing, and then eluting the retained shikimate salt with acetic acid. This resulted in pure shikimic acid (6.6 ± 0.1 wt % of the initial star anise powder, in duplicate experiments); identification and purity was assessed by NMR (confirming purity of the organic components) and TGA (left no ash, confirming no inorganic contaminants).…”

“…Briefly, literature precedent was followed and so a hexane wash was used to remove the oil, and the remaining tarry component was diluted with water and boiled with formaldehyde [38,56] to remove proteins as a brown precipitate. The resulting clear shikimic acid-rich amber solution was dried, and ca.…”