The electrophilic substitution of N-alkylated isocarbostyrils was examined in considerable detail. Bromination, acylation, nitration, and acid-catalyzed condensation with formaldehyde occurred exclusively at C-4 under relatively mild conditions. The acylation of isocarbostyrils has heretofore not been reported.The bromination of 2-methyl-5-nitroisocarbostyril in aqueous acetic acid gave 2-methyl-3,4-dihydro-3-hydroxy-4-bromo-5-nitroisocarbostyril (7) of unknown stereochemistry, as the sole product. When heated above its melting point, 7 lost the elements of water to give the "normal" product of bromination 8.In aqueous acetic acid, excess bromine was shown to convert isocarbostyrils to the corresponding 3,4-dihydro-3-hydroxy-4,4-dibromo derivatives whose structures were supported by spectral and degradative evidence.

After cooling to 20°the precipitate was filtered off and the filtrate was evaporated in vacuo.The residue solidified on standing and was purified as indicated in Table II.They are indebted to them for furnishing the testing data reported in Table I. We would also like to acknowledge the generous support by a research contract (DA-49-163-ID-2047) of this Project by the Office of the Surgeon General, United States Army Medical Research and Development Command under whose sponsorship this work was carried out.

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Oxazole-2-thione was prepared by the condensation of glycolic aldehyde and thiocyanic acid. It was shown by i.r. spectroscopy that oxazole-2-thione, as well as its 4-methyl- and 4,5-dimethyl derivatives, existed as the thione form in solution.

A description of the synthesis of epoxides from diary1 ketones and dimethylsulfonium methylide by a modified technique is given.The nuclear magnetic resonance spectra of several of the 11-substituted dibenzo[b,e]azepin-6-ones are interpreted on the basis of a slow interconversion between diastereomeric boat conformers in which the C-11 substituent is quasi axial or quasi equatorial.