SYNTHESIS OF AMIDINES – IMIDAZOLINE NITROXIDE DERIVATIVES – A NEW SERIES OF pH-SENSITIVE SPIN PROBES AND SPIN LABELS
T. A. BEREZINA, V. V. MARTIN, L. B. VOLODARSKY, V. V. KHRAMTSOV*, L. M. WEINER*
Novosibirsk Institute of Organic Chemistry; *Institute of Chemical Kinetics and Combustion, Siberian Division, Academy of Sciences of the USSR, Novosibirsk
Abstract: A synthesis of amidines, 4-(R-amino)-2,2,5,5-tetramethyl-3-imidazoline-l-oxyl derivatives, is described. The method is based on the alkaline hydrolysis of products of 1,3-dipolar cycloaddition of nitroxide, containing a nitrone grouping, with isocyanates. Structurally more complex spin labels were obtained by monoadduct of the above-mentioned nitrone-nitroxide with the toluene-2,6-diisocyanate modification. The resulting spin probes and spin labels may be used for measuring the local pH values within the range 1.8-4.6 in biological objects.
Russian Journal of Bioorganic Chemistry 1990, 16 (2):262-269