26990-82-9Relevant academic research and scientific papers
New syntheses of 2-alkylthio-4-oxo-3,4-dihydroquinazolines, 2-alkylthioquinazolines, as well as their hetero analogues
Gruner, Margit,Rehwald, Matthias,Eckert, Katrin,Gewald, Karl
, p. 2363 - 2377 (2007/10/03)
N-Chloroacetylanthranilic acid ethyl ester reacts with potassium thiocyanate in the presence of alcohol to give the (4-oxo-3,4-dihydroquinazolin-2-ylsulfanyl)acetic acid ester (3a). In the presence of water or amines the acetic acid derivative (3b) or the acetamide derivatives (3c,d) are obtained. 2-Amino-4-oxo-3,4-dihydroquinazolines (4) arise if vigorous reaction conditions are employed. Analogously, N-chloroacetyl derivatives of 5-membered heterocycles with enaminocarbonyl structure (5, 7, 9, 11, 13, 20, 23) react with potassium thiocyanate to yield thieno[2,3-d]-, thieno[3,2-d]-, imidazo[4,5-d]-, pyrrolo[3,2-d]-, and thiazolo[4,5-d]pyrimidines (6, 8, 10, 12, 14, 21, 24). Quinazolines (18, 19) are formed from the reaction of 2-chloroacetylaminoacetophenone (16a) and 2-chloroacetylaminobenzophenone (16b) with potassium thiocyanate and subsequent treatment of the intermediates with amines.
