Pc. Unangst et al., SYNTHESIS OF NOVEL 5-HYDROXY-3-ALKOXY-INDOLE-2-CARBOXAMIDES AND 5-HYDROXY-3-ALKYLTHIO-INDOLE-2-CARBOXAMIDES, Journal of heterocyclic chemistry, 33(6), 1996, pp. 1627-1630
The preparation of several novel 5-hydroxyindole-2-carboxamides is des
cribed. A 5-benzyloxyindole ester was elaborated to the 3-bromo, 3-hyd
roxy, and 3-alkoxy ester intermediates followed by conversion to the a
mide and debenzylation. A related 5-acetyloxy indole ester was convert
ed to 3-sulfinyl and 3-alkylthio intermediates before simultaneous ami
dation and removal of the 5-hydroxy protecting group.