Synthesis and Biological Evaluation of Reniochalistatins A-E and a Reniochalistatin E Analogue.

The total synthesis of reniochalistatins A-E, along with a reniochalistatin E analogue (inverso-E) was successfully achieved through Fmoc-based solid-phase peptide synthesis and subsequent macrolactamization with PyBOP and DIEA. The biological activities of these reniochalistatins and a key linear peptide intermediate were systematically evaluated. Among these seven synthesized compounds, linear reniochalistatin B was found to have potent activity against several cancer cell lines not shown by the cyclic reniochalistatin B counterpart.

Isolation and Synthesis of Misszrtine A: A Novel Indole Alkaloid From Marine Sponge-Associated sp. SCSIO XWS03F03.

A novel indole alkaloid, misszrtine A (), was isolated from marine sponge-derived fungus sp. SCSIO XWS03F03. The planar structure of was assigned by analysis of spectroscopic data, the absolute configuration of which was unambiguously determined by total synthesis.

Cytotoxicity Study of Cyclopentapeptide Analogues of Marine Natural Product Galaxamide towards Human Breast Cancer Cells.

Herein, we report the cytotoxicity of cyclopentapeptide analogues of marine natural product galaxamide towards breast carcinoma cells and the underlying mechanisms. We examined the effect of the novel galaxamide analogues on cancer cell proliferation by MTT assay and also further examined the most active compound for morphological changes using Hoechst33342 staining technique, induction of apoptosis, cell cycle phases, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) generation using flow cytometry in human breast cancer MCF-7 cells . Galaxamide and its analogues effectively induced toxicity in human hepatocellular carcinoma HepG2, human breast carcinoma MCF-7, human epitheloid cervix carcinoma HeLa, and human breast carcinoma MB-MDA-231 cell lines.