A Lawrence man was sentenced to seven years and three months in prison for marketing synthetic marijuana and other designer drugs around the world.

Bradley Miller was sentenced Monday after admitting he conspired with his brother, Clark Sloan, and his brother’s son, Jonathan, to manufacture and sell the drugs.

Federal prosecutors say the men’s business started at Persephone’s Journey in Lawrence. The business grew to include suppliers, retailers, wholesalers and business associates across the country, in Canada, South America, Europe and Asia.

The men made at least $3.3 million from the scheme.

Clark Sloan, of Tonganoxie, and Jonathan Sloan, of Lawrence, were convicted last September on 20 counts. Clark Sloan was sentenced to seven years and three months in prison, and his son got eight years.