The invention relates to medicine, and specifically to synthetic biologically active derivatives of carbopentoxysulfanilic acid. The novel substance comprises a (2,6-dichlorophenyl)amide salt of carbopentoxysulfanilic acid of general formula: where X is Na, K, NH 4 the drug may be contained in tablets, including sublingual tablets, or in capsules, or in suppositories, or in drops, or in mixtures, or in ointments, creams or other forms for application to the skin and mucosae, or in an oral-buccal film, or in a spray, or in a liquid for parenteral administration, or in chewing gum. A preparation having pronounced activity against herpes viruses is thus produced.
