Résumé : The following imidazolino[1,2-c]pyrimidines {A figure is presented} have been synthesised according to scheme A (1 → VI, p. 76) or scheme B (VIII → XV, p. 78). Compounds {A figure is presented} and {A figure is presented} have no effect on the growth of tobacco mosaic virus. The final products are characterised by their X-ray powder diffraction patterns. It is suggested that this simple method of identification should be used systematically in the case of compounds which do not melt sharply. © 1957.