Isatoic anhydride is an organic compound derived from anthranilic acid. A white solid, it is prepared by reaction of anthranilic acid with phosgene.
Reactions Hydrolysis gives carbon dioxide and anthranilic acid. Alcoholysis proceeds similarly, affording the ester: C6H4C2O3NH + ROH → C6H4(CO2R)(NH2) + CO2 Amines also effect ring-opening. Active methylene compounds and carbanions replace oxygen giving hydroxyquinolinone derivatives. Deprotonation followed by alkylation gives the N-substituted derivatives. Sodium azide gives the benzimidazolone via the isocyanate. Isatoic anhydride is used as a blowing agent in the polymer industry, an application that exploits its tendency to release CO2.
Uses Isatoic anhydride has been used as a precursor for the synthesis of methaqualone and related 4-quinazolinone-based pharmaceutical drugs, including: Antrafenine Atolide Cloperidone Diproqualone Pelanserin Nicafenine Molinazone SJ-733 Tioperidone Tranilast (actually made from acetanthranil) SGB 1534 U-29409 [31785-60-1]
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