Meclocycline is a semi-synthetic tetracycline prepared by dehydration of the 6-hydroxy group of chlortetracycline to yield an exocyclic 6-methylene. Meclocycline is a close structural analogue of methacycline. Like all tetracyclines, meclocycline shows broad spectrum antibacterial and antiprotozoan activity. Meclocycline has been extensively cited in the literature with over 400 references.