1.2.3- Benzotriazin-4

Reactions of compounds 23 with 2-chloromethoxyethyl acetate lead to N-alkylation products 27, which are hydrolyzed to form4-(2-hydroxyethoxymethyl)-1,2,4-benzotriazine 28 (82JHC497). 

The condensation of 3-amino-1,2,4-benzotriazine 1-oxides 29 with a-halo-carbonyl compounds results in imidazo[2,l-c]-l,2,4-benzotiiazine 1-oxides 30 (82JHC61, 86MI). 

The reaction of benzofurazan iV-oxide with diethylamine affords 3-methyl-1,2,4-benzotriazine 4-oxide 160 (79T681, 82T1793). 

In some cases, the position of the N-oxidation depends on the temperature. The reaction of 3-phenyl-1,2,4-benzotiiazine 172 with peracetic acid affords 3-phenyl-l,2,4-benzotriazine 1-oxide 173 at 50°C and 2-oxide 174 at room temperature (57JCS3186). Only the 1-oxide 175 was obtained by the oxidation of 3-unsubstituted 1,2,4-benzotriazine 176. The oxidation of 3-methyl-1,2,4-benzo-triazine 176 (R = Me) under the same conditions results in a mixture of 3-methyl-l,2,4-benzotriazine 1-oxide 175 and 2-oxide 177 in 25 and 10% yields, respectively. 

CN 5-(dimethylamino)-9-methyl-2-propyl-l/7-pyrazolo[ 1,2-a][ 1,2,4]benzotriazine-1,3(2//)-dione... 

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