The present invention relates to substance 3787-5-1 represented by formula (I) and pharmaceutically permissible salts thereof. Substance 3787-5-1 is useful for the prevention and treatment of a disease caused by a cell proliferative disorder, particularly a malignant tumor, because it has antineoplastic activity acting alone and also enhances the antineoplastic activity of other antineoplastic agents. This substance can be produced by culturing a microorganism of the genus Phytohabitans that is capable of producing substance 3787-5-1, particularly Phytohabitans sp. 3787-5, and collecting substance 3787-5-1 from the culture product thereof.
