The initial step in the present investigation was the preparation of the α-methyl-d-glucuronoside (ii) by the oxidation of α-methyl-d-glucoside (i) with an equilibrium mixture of nitrogen dioxide and nitrogen tetroxide in chloroform and carbon tetrachloride. [formula here]. The uronic acids in general will be discussed below, especially d-glucuronic acid (iii) which can not be purchased and hence must be synthesised or isolated from natural products.