Disclosed herein are novel 1,3-dihydro-5-isobenzofurancarbonitrile derivatives represented by Formula 1, or pharmaceutically acceptable salts thereof. Also disclosed is a pharmaceutical composition for treating or preventing premature ejaculation including the compound. The 1,3-dihydro-5-isobenzofurancarbonitrile derivatives have a short half-life and inhibit the ejaculation process by selectively inhibiting serotonin reuptake via a serotonin reuptake transporter present in a presynaptic neuron. Thus, the compounds are useful in the treatment and prevention of premature ejaculation.
