| abstract |
Methods for the synthesis of heterocyclic compounds such as benzimidazole carboxylic acid core structures having Formula Ia-1 and its synthetic intermediates are provided: wherein Z, X1, X2, X5, R2 and R10 are as defined in Present. The compounds of Formula Ia-1 and their synthetic intermediates can be used to prepare heterocyclic derivatives such as benzimidazole derivatives. |