The present invention creates a novel antiangiogenic agent and provides an antitumor agent which shows high safety as compared with conventional antitumor agents, has a sure effect and is able to be administered for a long period. That is, it provides an
indole compound represented by the following formula (I), its pharmacologically acceptable salt or hydrates thereof. 1 In the formula, R.sup.1 represents
hydrogen atom, a
halogen atom or cyano group; R.sup.2 and R.sup.3 are the same as or different from and each represents
hydrogen atom, a C.sub.1-C.sub.4 lower
alkyl group or a
halogen atom; R.sup.4 represents
hydrogen atom or a C.sub.1-C.sub.4 lower
alkyl group; and the ring A represents cyanophenyl group, aminosulfonylphenyl group, aminopyridyl group, aminopyrimidyl group, a halopyridyl group or cyanothiophenyl group, provided that the case where all of R.sup.1, R.sup.2 and R.sup.3 are hydrogen atoms, where both R.sup.2 and R.sup.3 are hydrogen atoms or where the ring A is aminosulfonyl group and both R.sup.1 and R.sup.2 are
halogen atoms is excluded. Further, when the ring A is cyanophenyl group, 2-amino-5-pyridyl group or a 2-halo-5-pyridyl group and R.sup.1 is cyano group or a halogen atom, at least one of R.sup.2 and R.sup.3 should not be a
hydrogen atom.