Studies on the chemical synthesis of potential antimetabolites. XXIV. The synthesis and antitumor activities of p-tosylhydrazones of 2-formylpyridine 1-oxides and 2-formylazoles 3-oxides.
We have developed a new method for the synthesis of 2-formyl-thiazole 3-oxide and 2-formyl-4-methylthiopyridine 1-oxide. Several new p-tosylhydrazones of pyridine, thiazole and imidazole derivatives were prepared. It was found that some of the hydrazones of the pyridine 1-oxides series were active in vivo against ascites sarcoma 180, whereas p-tosylhydrazones of the azole-N-oxide series were less active or inactive.
moiety (position Y). These nickel pre-catalysts are highly active in ethylene polymerization with the addition of very little amount of aluminum cocatalysts, leading to the formation of polyethylenes with molecular weights of well above one million. Electron-donating substituents make the catalysts sensitive to polymerization temperature. In contrast, the catalysts bearing electron-withdrawing NO2 substituents