Calanolide A

Calanolide A is a new, experimental non-nucleoside reverse transcriptase inhibitor (NNRTI) first acquired from Calophylum lanigerum trees in Malaysia. The U.S. National Cancer Institute tested calanolide A as a possible cancer treatment, but had no effect. It was later found to have potent anti-HIV activity. Since the plant source is relatively rare, a total synthesis was developed in 1996. The form in current use is formulated for oral administration and produced by Sarawak MediChem in Lemont, Illinois.

Calanolide A is unique among NNRTIs in that it may bind two distinct sites in reverse transcriptase.