Kondensierte 1.2-Dithiole, I. Synthese von Thiolutin und verwandten Verbindungen

Dithiolopyrrolones are Prochelators that are Activated by Glutathione

Dithiolopyrrolones (DTPs), such as holomycin, are natural products that hold promise as scaffolds for antibiotics as they exhibit inhibitory activity against antibiotic-resistant pathogens. They consist of a unique bicyclic core containing a disulfide that is crucial for their biological activity. Herein, we establish the DTPs as prochelators. We show that the disulfides are reduced at cellular gluathione levels. This activates the drugs and initiates interactions with targets, particularly metal coordination. In addition, we report an expedient synthesis for the DTPs thiolutin and aureothricin, providing facile access to important natural DTPs and derivatives thereof.

Dithiolopyrrolones: biosynthesis, synthesis, and activity of a unique class of disulfide-containing antibiotics

Covering: up to 2014. Dithiolopyrrolone (DTP) group antibiotics were first isolated in the early half of the 20th century, but only recently has research been reawakened by insights gained from the synthesis and biosynthesis of this structurally intriguing class of molecules. DTPs are characterized by an electronically unique bicyclic structure, which contains a compact disulfide bridge between two ene-thiols. Points of diversity within the compound class occur outside of the bicyclic core, at the two amide nitrogens. Such modifications distinguish three of the most well studied members of the class, holomycin, thiolutin, and aureothricin; the DTP core has also more recently been identified in the marine antibiotic thiomarinol, in which it is linked to a marinolic acid moiety, analog of the FDA-approved topical antibiotic Bactroban® (GlaxoSmithKline). Dithiolopyrrolones exhibit relatively broad-spectrum antibiotic activity against many Gram-positive and Gram-negative bacteria, as well as strains of Mycobacterium tuberculosis. Additionally, they have been shown to exhibit potent and selective anti-cancer activity. Despite this promising profile, there is still much unknown about the mechanisms of action for DTPs. Early reports suggested that they inhibit yeast growth at the level of transcription and that this effect is largely responsible for their distinctive microbial static properties; a similar mechanism is supported in bacteria. Elucidation of biosynthetic pathways for holomycin in Streptomyces clavuligerus and Yersinia ruckeri and thiomarinol in Alteromonas rava sp. nov. SANK 73390, have contributed evidence suggesting that multiple mechanisms may be operative in the activity of these compounds. This review will comprehensively cover the history and development of dithiolopyrrolones with particular emphasis on the biosynthesis, synthesis, biological activity and mechanism of action.

Substituted 6-amino-4H-[1,2]dithiolo[4,3-b]pyrrol-5-ones: Synthesis, structure–activity relationships, and cytotoxic activity on selected human cancer cell lines

An efficient synthesis and the cytotoxic activity of a series of substituted 6-amino-4H-[1,2]dithiolo[4,3-b]pyrrol-5-ones 1a-q is described. The synthesis was accomplished in an expedient manner (seven-steps) from commercially available starting materials. Several of the derivatives tested demonstrated significant in vitro cytotoxic activity against the human cancer cell lines H460 (7nM) and LCC6 (> or =28nM). Following SAR and pharmacokinetic studies a derivative was further evaluated for its in vivo anti-tumor activity against a highly angiogenic human melanoma xenograft where it demonstrated significant efficacy as a mono-therapy and in combination with Taxol and Cisplatin.

Expedient total synthesis of pyrrothine natural products and analogs

This paper describes an expedient and straightforward total synthesis of the two pyrrothine natural products holomycin (7 steps, 11% overall) and xenorhabdin I (7 steps, 11% overall) and analogs thereof via a common late-stage intermediate. The pathway proceeds via the pyrrothine hydrochloride intermediate (6 steps, 17% overall) which also gave access to very fast synthesis of analogs as demonstrated by the synthesis of , and (7 steps, 11-12% overall).