Ambewelamides A and B, antineoplastic epidithiapiperazinediones isolated from the lichen Usnea sp.

Ambewelamides A and B, antineoplastic epidithiapiperazinediones isolated from the lichen Usnea sp. Usnic Acid Derivatives with Cytotoxic and Antifungal Activities from the Lichen <i>Usnea longissima</i> Usnic Acid Derivatives with Cytotoxic and Antifungal Activities from the Lichen <i>Usnea longissima</i> Usimines A−C, Bioactive Usnic Acid Derivatives from the Antarctic Lichen <i>Stereocaulon alpinum</i> Usimines A−C, Bioactive Usnic Acid Derivatives from the Antarctic Lichen <i>Stereocaulon alpinum</i> Stictic Acid Derivatives from the Lichen <i>Usnea </i><i>articulata</i> and Their Antioxidant Activities Amathaspiramides A−F, Novel Brominated Alkaloids from the Marine Bryozoan <i>Amathia </i><i>w</i><i>ilsoni</i> Antineoplastic Agents. 558. <i>Ampelocissus</i> sp. Cancer Cell Growth Inhibitory Constituents Ceratamines A and B, Antimitotic Heterocyclic Alkaloids Isolated from the Marine Sponge Pseudoceratina sp. Collected in Papua New Guinea Ophiobolin Sesterterpenoids and Pyrrolidine Alkaloids from the Sponge‐Derived Fungus Aspergillus ustus