87081-36-5

Leptomycin A is an inhibitor of CRM1 (exportin 1) that blocks CRM1 interaction with nuclear export signals, preventing the nuclear export of a broad range of proteins. Leptomycin A inhibits Rev translocation, though less potently than leptomycin B (Item No. 10004976) with IC₅₀ values of 0.8 and 0.1 nM, respectively after 7 hours. Rev export to the cytoplasm is required for HIV-1 replication. Leptomycin A was originally identified as an antifungal agent.

Leptomycin A, a methyl analogue of leptomycin B, is a minor component of the leptomycin complex produced by selected Streptomyces species. Leptomycin B is a potent inhibitor of the nuclear transport receptor CRM1. Leptomycin A is also likely to inhibit nuclear transport and may offer differences in exporter selectivity. Leptomycin A shows antimicrobial activity against Schizosaccaromyces pombe and Mucor rouxianus.

ChEBI: A leptomycin having all-trans double bonds and a seventh methyl substituent at position 17.