A primary object of the present invention is to provide a novel compound having LSD1-selective inhibitory activity and having an antitumor/anticancer action, an antiviral action, and the like. As means for achieving such object, provided is a compound represented by the following formula (I) or a pharmaceutically acceptable salt thereof:[in the formula, R1 to R5, A, and *1 to *3 are as defined in Description].
