Abstract: A process for the preparation of a mixture of 3?,6?-dihydroxy-6-nitrospiro[2-benzofuran-3,9?-xanthene]-1-one and 3?,6?-dihydroxy-5-nitrospiro[2-benzofuran-3,9?- xanthene]-1-one comprising the steps of:- (a) reacting 4-nitrophthalic acid or 4-nitrophthalic anhydride with benzene-1,3-diol in methanesulphonic acid; (b) quenching the reaction in step (a) with a solvent to precipitate product; (c) isolating the precipitate; (d) heating the precipitate in water in order to hydrolyse any methansulphonic acid ester present.

Abstract: A process for the preparation of cholyl-L-lysine comprising the steps of: —(a) reacting N-?-CBZ-cholyl-L-lysine with a hydrogen source in the presence of a catalyst in a solvent comprising one or more alkanols; (b) removing the catalyst; (c) optionally diluting the resulting reaction mixture with water and optionally adjusting the pH of the resultant reaction mixture to a pH less than or equal to about 4; (d) removing the bulk of the alkanol whilst ensuring that the alkanol content of the resultant mixture is maintained above about 3% w/w of the remaining mixture; (e) extracting the resultant mixture from step (d) with an organic solvent; (f) adjusting the pH of the aqueous layer to a pH of about 4.5 or greater to precipitate cholyl-L-lysine; (g) isolate the precipitate.