2-Amino-4-butoxymethylthiazole等の合成及び抗菌力について

抄録

The reaction of 2-acetamino-4-methyl-5-bromothiazole (I) and sodium butoxide failed to give the objective 2-acetamino-4-methyl-5-butoxythiazole (II) under the various conditions tested and only a substance of unknown structure, melting at over 350°, was obtained. Bromination of butoxyacetone (V) followed by reaction with thiourea gave a minute amount of 2-aminothiazole derivative whose acetate melted at 116-117°. The isomer of (II), i. e. 2-acetamino-4-butoxymethylthiazole (XIII) was obtained by the acetylation of 2-amino-4-butoxymethylthiazole (XII), formed in a good yield by the condensation of thiourea and 1-butoxy-3-chloro-2-propanone (XI) obtained by the hydro-chloric acid decomposition of the diazoketone (X). Attempted preparation of 2-amino-5-butoxythiazole [Fig. 2, (III)] by the bromination of butoxyacetaldehyde diethyl acetal (I) followed by condensation with thiourea failed to provide a crystalline product, although the formation of 2-aminothiazole derivatives was proved by the diazo color reaction. The antibacterial activity of the thiazole derivatives thereby prepared are shown in Table I, and the ultraviolet absorption maxima of the thiazole derivatives reported in the present and the preceding papers are shown in Table II.