Tirandamycin

The tirandamycins are a small group of natural products that contain a bicyclic ketal system and a tetramic acid moiety, the latter of which is found in different natural products from a variety of sources and which is characterized by a 2,4-pyrrolidinedione ring system. Members of this structural family have shown a wide range of biological activities like in antiparasitic, antifungal and anti-HIV evaluations, and furthermore, have shown potential usefulness because of their potent antibacterial properties. Streptolydigin, an analogue of the tirandamycins, is known to function as an antibacterial agent through inhibiting the chain initiation and elongation steps RNA polymerase transcription. The structural diversity in the tirandamycin family originates from the different oxidation patterns observed in the bicycic ketal system, and these modifications are determinant features for the bioactivity associated with these molecules.