The regioselectivity of the Richter cyclization for a series of 4-halo-2-[(3,4,5 trimethoxyphenyl)ethynyl]anilines has been studied to obtain trimethoxybenzoyl-1H-indazoles, heteroanalogs of combretastatin. In aqueous acetonitrile, cinnolin-4(1H)-ones, which are products of 6-endo-dig cyclization, are formed along with 1H-indazoles, products of 5-exo-dig cyclization. In a DMSO : H2O mixture, 3-aroyl-1H-indazoles are formed exclusively. In the case of 2-[(4-methoxyphenyl)ethynyl]-4-haloanilines, the 5-exo-dig cyclization proceeds independently on the used solvent. Among the prepared trimethoxybenzoyl-1H-indazoles, the 5-chloro-substituted indazole showed the highest cytotoxicity, while the fluoro-substituted indazole exhibited no severe cytotoxicity.