ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis and Photosynthesis-Inhibiting Activity of Some Anilides of Substituted Pyrazine-2-carboxylic Acids

M. Doležal, J. Hartl, M. Miletín, M. Macháček, and K. Kráľová

Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, CZ-500 05 Hradec Králové

Abstract: Alkylation of pyrazine-2-carboxylic acid and 6-chloropyrazine-2-carboxylic acid with radicals generated by silver nitrate-catalyzed oxidative decarboxylation of pivalic acid afforded 5-(1,1-dimethylethyl)pyrazine-2-carboxylic acid and 6-chloro-5-(1,1-dimethylethyl)pyrazine-2 acid. Condensation of chlorides of the latter three halogenated and/or alkylated pyrazine-2-carboxylic acids with ring-substituted anilines yielded a series of anilides of 6-chloropyrazine-2-carboxylic, 5-(1,1-dimethylethyl)pyrazine-2-carboxylic or 6-chloro-5-(1,1-dimethylethyl)pyrazine-2-carboxylic acids. Some of these anilides showed a moderate inhibitory effect upon the oxygen evolution rate in spinach chloroplasts. The most active inhibitor was 5-chloro-2-hydroxyanilide of 6-chloropyrazine-2-carboxylic acid (IC₅₀ = 0.008 mmol dm^-3). The introduction of chlorine in the pyrazine moiety led to an increased photosynthesis-inhibiting activity.

Full paper in Portable Document Format: 532a126.pdf

Chemical Papers 53 (2) 126–130 (1999)