The Bengamides: A Mini-Review of Natural Sources, Analogues, Biological Properties, Biosynthetic Origins, and Future Prospects.

This review focuses entirely on the natural bengamides and selected synthetic analogues that have inspired decades of research. Bengamide A was first reported in 1986 from the sponge Jaspis cf. coriacea, and bengamide-containing sponges have been gathered from many biogeographic sites.

Study of marine natural products including resorcyclic acid lactones from Humicola fuscoatra that reactivate latent HIV-1 expression in an in vitro model of central memory CD4+ T cells.

An extract of Humicola fuscoatra (UCSC strain no. 108111A) was shown to reactivate latent HIV-1 expression in an in vitro model of central memory CD4+ T cells. We report the bioassay-guided isolation and structure determination of several resorcyclic acid lactones, including four known compounds, radicicol (1, aka.

Myxobacteria versus sponge-derived alkaloids: the bengamide family identified as potent immune modulating agents by scrutiny of LC-MS/ELSD libraries.

A nuclear factor-κB (NF-κB) luciferase assay has been employed to identify the bengamides, previously known for their anti-tumor activity, as a new class of immune modulators. A unique element of this study was that the bengamide analogs were isolated from two disparate sources, Myxococcus virescens (bacterium) and Jaspis coriacea (sponge). Comparative LC-MS/ELSD and NMR analysis facilitated the isolation of M.

A spectroscopic investigation of a tridentate Cu-complex mimicking the tyrosine-histidine cross-link of cytochrome C oxidase.

Heme-copper oxidases have a crucial role in the energy transduction mechanism, catalyzing the reduction of dioxygen to water. The reduction of dioxygen takes place at the binuclear center, which contains heme a3 and CuB. The X-ray crystal structures have revealed that the C6' of tyrosine 244 (bovine heart numbering) is cross-linked to a nitrogen of histidine 240, a ligand to CuB.

NMR strategy for unraveling structures of bioactive sponge-derived oxy-polyhalogenated diphenyl ethers.

The overexpression of the Mcl-1 protein in cancerous cells results in the sequestering of Bak, a key component in the regulation of normal cell apoptosis. Our investigation of the ability of marine-derived small-molecule natural products to inhibit this protein-protein interaction led to the isolation of several bioactive oxy-polyhalogenated diphenyl ethers. A semipure extract, previously obtained from Dysidea (Lamellodysidea) herbacea and preserved in our repository, along with an untouched Dysidea granulosa marine sponge afforded 13 distinct oxy-polyhalogenated diphenyl ethers.

A selective account of effective paradigms and significant outcomes in the discovery of inspirational marine natural products.

Marine natural products continue to be a source of significant molecular structures that serve as a stimulus to seed further significant research. This account reviews some of the major advances in the study of marine biomolecules made at UC Santa Cruz over more than three decades. The continuing challenge of discovery and characterization of what we term "inspirational molecular structures" will be presented in a comprehensive fashion.

Structure revision of spiroleucettadine, a sponge alkaloid with a bicyclic core meager in H-atoms.

Our 2004 disclosure of the amino hemiketal-containing spiroleucettadine was met with keen interest by the natural products and synthetic communities. As repeated efforts to synthesize spiroleucettadine failed and questions regarding the original structure elucidation process arose, evidence mounted against the validity of the proposed structure. The low ratio of H/C in the core of spiroleucattadine complicated the original structure elucidation process.

Synthesis and structural characterization of cross-linked histidine-phenol Cu(ii) complexes as cytochrome c oxidase active site models.

Tridentate cross-linked histidine-phenol Cu(ii) ether and ester complexes, chemical analogs of the active site of several heme-copper oxidases, have been synthesized and crystallized.

Sponge-derived fijianolide polyketide class: further evaluation of their structural and cytotoxicity properties.

The sponge-derived polyketide macrolides fijianolides A (1) and B (2), isolaulimalide and laulimalide, have taxol-like microtubule-stabilizing activity, and the latter exhibits potent cytotoxicity. Insight on the biogeographical and phenotypic variations of Cacospongia mycofijiensis is presented that will enable a future study of the biosynthetic pathway that produces the fijianolides. In addition to fijianolides A and B, six new fijianolides, D-I (7-12), were isolated, each with modifications to the C-20 side chain of the macrolide ring.

Bromopyrrole carboxamide biosynthetic products from the Caribbean sponge Agelas dispar.

Two new bromopyrrole alkaloids, dispyrin (6) and dibromoagelaspongin methyl ether (12), were isolated from the Caribbean sponge Agelas dispar, collected near the Venezuelan island La Blanquilla, and their structures were elucidated from spectroscopic data analysis. Dispyrin (6) contains a novel bromopyrrole tyramine motif that has no precedent in marine natural products chemistry and represents a notable variation from the oroidin class compounds consistently produced by species of Agelas in general. Compounds isolated from Caribbean Agelas species were found to possess a unique biogeographical bromination trend.

Accelerating the discovery of biologically active small molecules using a high-throughput yeast halo assay.

The budding yeast Saccharomyces cerevisiae, a powerful model system for the study of basic eukaryotic cell biology, has been used increasingly as a screening tool for the identification of bioactive small molecules. We have developed a novel yeast toxicity screen that is easily automated and compatible with high-throughput screening robotics. The new screen is quantitative and allows inhibitory potencies to be determined, since the diffusion of the sample provides a concentration gradient and a corresponding toxicity halo.

Facile synthesis of highly functionalized N-methyl amino acid esters without side-chain protection.

[reaction: see text] The facile, two-pot synthesis of N-methyl amino acid esters by way of reductive amination is presented. Side chain protection schemes are not required, the starting materials are all commercially available, and the synthetic method is straightforward and affords desired product in very high yield.