“…Several studies demonstrated an antibacterial activity against Gram-positive, but not against Gram-negative, bacteria ( 50 , 51 ). Furthermore, rubrolides seem to have antiviral activity ( 37 , 49 , 52 ), and, similar to the diorcinols, some rubrolides have antitumor activity ( 46 , 47 , 49 , 53 ). Interestingly, synthetic rubrolide analogues, but especially lactams derived from rubrolides, revealed antibiofilm activity against Gram-positive and Gram-negative bacteria ( 54 – 56 ).…”