THE structure of vitamin Bx was made certain by its synthesis, recently announced from the laboratory of Prof. Williams of Columbia University (see NATURE, Aug. 29, p. 372), and this has now been repeated elsewhere. Grewe (Hoppe-Seyler's Zeitschrift fiir physio-logische Chemie, 242, 89; 1936), working in Windaus's laboratory at Gottingen, describes the preparation of the pyrimidine half of the molecule, and completely confirms the latest formula put forward by Williams, though mention is only made of Williams's earlier suggestions which he himself has now modified. Grewe goes on to state that he had intended to work out a synthesis of the vitamin from the new pyrimidine derivative when he learned, through Prof. Windaus, that Andersag and Westphal had already accomplished this in the scientific laboratories of the I.G. at Elberfeld, and that patent protection had been sought. Prof. Williams's work was carried out with the collaboration of Merck and Co., Inc., Rahway, N.J.; it seems, therefore, on the cards that there may be some interesting developments in the patent field, should the synthesis of vitamin Bx become practicable on a commercial scale.