1960 年 80 巻 12 号 p. 1735-1738
Acetylation of the sodium salts of N1-(5-methyl-3-isoxazolyl) sulfanilamide (VII) and N1-(2-phenyl-3-pyrazolyl) sulfanilamide (VIII) with acetic anhydride gave N1-acetylated derivatives (V and VI) by selective acetylation of N1-position. Acetylation of (VII) and (VIII) with acetic anhydride in the presence of pyridine, however, afforded N4-acetylated derivative (IX) in a good yield from (VII), instead of (V), while (VI) was obtained from (VIII) but in a smaller yield than that from the sodium salt. Boiling of (V) and (VI) in pyridine resulted in facile rearrangement of the acetyl group from N1- to N4-position. This rearrangement reaction was especially easy in (V) which formed N4-acetylated compound in a good yield merely by being allowed to stand in pyridine at ordinary temperature for a few days. Ultraviolet absorption spectra of acetylated derivatives of several kinds of sulfanilamide are also described.