Solid-phase synthesis of 2-cyanoquinazolin-4(3H)-one and 2,3-dihydrooxazolo[2,3-b]quinazolin-5-one derivatives utilizing resin-bound anthranilic acid derivatives

We were able to obtain 2-cyanoquinazolin-4(3H)-ones 11 in 35–60% four-step overall isolated yields and 2,3-dihydrooxazolo[2,3-b]quinazolin-5-ones 12 in 20–71% four-step overall isolated yields utilizing polymer-bound anthranilic acid derivatives 1, and 6-amino-2-cyanoquinazolin-4(3H)-ones 19 in 30–44% six-step overall isolated yields making use of anthranilic acid derivative resin 2 via dithiazole resins 10 and 17. The reactions on solid phase were monitored by single bead ATR-FTIR spectroscopic method.