Marcytoglobosins A and B, Cytochalasans From a Marine Sponge Associated Chaetomium globosum 162105 Fungus.

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity.

New NF-κB Inhibitory Steroids from the Marine Sponge Dysidea avara Collected from the South China Sea.

Chemical investigation of the marine sponge Dysidea avara, collected from the South China Sea, yielded 13 steroids, including nine new (1-9) and four known (10-13) ones. The new structures were elucidated as (3S,14R)-3,14-dihydroxycholesta-5,8-dien-7-one (1), (22E,24R)-7α-ethoxy-5α,6α-epoxyergosta-8(14),22-dien-3β-ol (2), 3β-hydroxy-7α-ethoxy-5α,6α-epoxy-8(14)-cholestene (3), 3β,5α-dihydroxy-6α-ethoxychofesta-7,9(11)-diene (4), 3β,5α-dihydroxy-6β-ethoxycholest-7-ene (5), (22E,24R)-24-ethoxy-3β,5α-dihydroxy-6β-ethoxyergosta-7,22-diene (6), (22E)-3β,5α-dihydroxy-6β-ethoxycholesta-7,22-diene (7), 24-ethoxy-3β,5α-dihydroxy-6β-ethoxycholest-7-ene (8 and 9), by extensive spectroscopic analyses, such as HR-ESI-MS, 1D and 2D NMR data. The absolute configuration of 1 was assigned by comparison the experimental ECD spectra with the calculated ones.