Regioselective quinazoline C2 modifications through the azide–tetrazole tautomeric equilibrium

• Dāgs Dāvis Līpiņš,
• Andris Jeminejs,
• Una Ušacka,
• Anatoly Mishnev,
• Māris Turks and
• Irina Novosjolova

Beilstein J. Org. Chem. 2024, 20, 675–683, doi:10.3762/bjoc.20.61

• : aromatic nucleophilic substitution; azide–tetrazole equilibrium; 4-azido-2-sulfonylquinazolines; quinazolines; sulfonyl group dance; Introduction The quinazoline core is a privileged structure with a wide range of applications. Quinazoline derivatives exhibit a broad spectrum of biological activities

• terazosin and prazosin [20]. Herein, we report the use of the sulfonyl group dance to synthesize novel 4-azido-2-sulfonylquinazolines and their C2-selective modification in SNAr reactions. In addition, we offer an approach for the synthesis of terazosin and prazosin, known medications against hypertension

• , using sulfonyl group dance products. Results and Discussion Synthesis of 4-azido-2-sulfonylquinazolines We started our experiments with commercially available 2,4-dichloroquinazoline (1a). It was treated with sodium 4-methylphenylsulfinate in order to yield 4-sulfonylquinazoline 2a (Scheme 2), but the