Glenthmycin A is a member of the C-20 nortetromycin family of spirotetronate polyketides reported by Khalil and co-workers University of Queensland, Australia in 2022. Structurally, glenthmycin A is the desmethyl analogue of tetromycin C5 reported by Tomio and colleagues at Microbial Chemical Research Foundation (Institute of Microbial Chemistry), Japan in 1996. Glenthmycin A is a potent antibacterial with activity against Gram-positive antibiotic -susceptible and -resistant strains of S. aureus and E. faecalis.