... Chim. ¡tal, 76,131 (1946). (5) A. Katritzky, Ed., "Advances in Heterocyclic Chemistry", Vol. 2, Academic Press, New York, NY, 1963, pp. 396-397. ... (7) A. Katritzky and J. Lagowski, "Chemistry of the Hetero- cyclic iV-oxides", Academic Press, New York, NY, 1971, pp. 236,240-241. ...