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Anthranilonitrile reacting with .[brmic acid at room temperature Jbr three days gave 64% of 3-(2-cvanophenyl)quinazolin-4(3H)-one. Under similar conditions anthranilic acid, 4-nitroaniline, and 2,5-dichloroaniline were Nz/brmylated in good yields.Keywords: anthranilonitrile, 3-(2-cyanophenyl)quinazolin-4(3H)-one, N-lbrmylation.The title quinazolinone was obtained for the first time quite recently [1] by a two-step reaction involving heating of anthranilonitrile (!) with an excess of tbrmic acid in boiling toluene (N-formylation) followed by treatment of the crude product with thionyl chloride and additional amount of 1. The yield of 3-(2-cyanophenyl)quinazolin-4(3H)-one (2) was very low (9%).Recently we have found out that, in contrast to the rather drastic conditions commonly used for N-formylation of anilines [2-4], anthranilic acid, 4-nitroaniline, and 2,5-dichloroaniline react with formic acid at room temperature. The appropriate N-formyl derivatives precipitate from the solutions in good yields as crystalline solids (Scheme 1). This result is rather unexpected, considering the low P/(j values of the anilines. Babayev's conditions is obtained in moderate yield (40%), Moreover, it is contaminated by several impurities. Thus, we assumed that an improvement in N-formylation of 1, using our conditions for formylation of anilines, would lead to a substantial increase in the total yield of 2. Unexpectedly, 1 dissolved in an excess of anhydrous formic acid and, when left for three days at 20-22~ afforded the title quinazolinone 2 in 64% yield (Scheme 2).

From commercially available chiral building blocks, we have developed methods for the syntheses of imidazole derivatives that contain a chiral alkyl substituent at ring atom. These compounds are suitable for further transformation into Nalkyl purine derivatives.

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Electron ionization (70 eV) mass spectra, double-stage (MS 2) 10 eV collision-induced dissociation (CID) production mass spectra of molecular ions and triple-stage (MS 3) sequential production mass spectra of major fragment ions are reported for the parent Nphenyl and the isomeric ortho-, meta-and para-N-chlorophenyl-and N-bromophenyl-2-aminobenzamidines. Dissociation is greatly influenced by an ortho effect that favors the loss of ortho H atoms and particularly the loss of the ortho halogen substituents. Dissociation occurs via a two-step intramolecular aromatic substitution reaction and a distonic-ion intermediate inhibits scrambling of ring hydrogens thus favoring the loss of the ortho substituents. The ortho isomers form an abundant and diagnostic [M-X] + fragment ion (X = Cl, Br) and are easily distinguished. Protonated 2-(1H-benzimidazol-2-yl)-phenylammonium ions are likely formed; they dissociate mainly by NH 3 loss upon CID and react readily with pyridine by proton transfer.