An Interaction of 2-Thiazoleacetonitriles with N-(2-Chloroacetyl)anthranilic Acid Ester

The title ester was found to react with 2-benzothiazoleacetonitrile yielding 3-(2-benzothiazolyl)-2,4-dihydropyrrolo[1,2-a]quinazoline-1,5-dione. At the same time 4-aryl-2-thiazoleacetonitriles gave 3,4-dihydro-β ,4-dioxo-α,δ-bis(4-aryl-2-thiazolyl)-2-quinazolinepentanenitriles potassium salts under identical conditions. These results were explained in terms of different solubility of the intermediate compounds. Upon acidification the obtained salts were shown to undergo intramolecular Thorpe addition leading to the 3-amino-2,4-bis(4-aryl-2-thiazolyl)-4-[4(3H)-oxo-2-quinazolinyl] -2-cyclopenten-1-ones. Above mentioned pyrrolo[1,2-a]quinazoline derivative was treated with benzylamines and active methylene nitriles to yield β-(2-benzothiazolyl)-N-arylmethyl-3, 4-dihydro-4-oxo-2-quinazolinepropanamides and 2-substituted 3-amino-4-(2-benzothiazolyl)-4-[4(3H)-oxo-2-quinazolinyl]-2-cyclopenten-1-ones, respectively.