Tuaimenals B-H, Merosesquiterpenes from the Irish Deep-Sea Soft Coral with Bioactivity against Cervical Cancer Cell Lines.

Previous chemical investigation of the Irish deep-sea soft coral led to the identification of tuaimenal A (), a new merosesquiterpene containing a highly substituted chromene core and modest cytotoxicity against cervical cancer. Further MS/MS and NMR-guided investigation of this octocoral has resulted in the isolation and characterization of seven additional tuaimenal analogs, B-H (-), as well as two known A-ring aromatized steroids (, ), and additional tuaimenal A (). Tuaimenals B, F, and G (, , ), bearing an oxygen at the C position, as well as monocyclic tuaimenal H (), show increased cervical cancer inhibition profiles in comparison to that of .

Dimethylmyricacene: An In Vitro and In Silico Study of a Semisynthetic Non-Camptothecin Derivative Compound, Targeting Human DNA Topoisomerase 1B.

Human topoisomerase 1B regulates the topological state of supercoiled DNA enabling all fundamental cell processes. This enzyme, which is the unique molecular target of the natural anticancer compound camptothecin, acts by nicking one DNA strand and forming a transient protein-DNA covalent complex. The interaction of human topoisomerase 1B and dimethylmyricacene, a compound prepared semisynthetically from myricanol extracted from root bark, was investigated using enzymatic activity assays and molecular docking procedures.

Crannenols A-D, Sesquiterpenoids from the Irish Deep-Sea Soft Coral .

Four undescribed sesquiterpenoids, crannenols A-D (-), have been isolated from CHCl and MeOH extracts of the deep-sea bamboo coral . The corals were collected from a submarine canyon on the edge of Ireland's Porcupine Bank via a remotely operated vehicle. The structure elucidation of these (,)-α-farnesene derivatives was achieved using a combination of 1D and 2D NMR, electron impact (, ), and electrospray ionization (, ) mass spectrometry.

From Antarctica to cancer research: a novel human DNA topoisomerase 1B inhibitor from Antarctic sponge .

Nature has been always a great source of possible lead compounds to develop new drugs against several diseases. Here we report the identification of a natural compound, membranoid G, derived from the Antarctic sponge displaying an inhibitory activity against human DNA topoisomerase 1B. The experiments indicate that membranoid G, when pre-incubated with the enzyme, strongly and irreversibly inhibits the relaxation of supercoiled DNA.