73956-17-9Relevant academic research and scientific papers
Structure elucidation of colibactin and its DNA cross-links
Xue, Mengzhao,Kim, Chung Sub,Healy, Alan R.,Wernke, Kevin M.,Wang, Zhixun,Frischling, Madeline C.,Shine, Emilee E.,Wang, Weiwei,Herzon, Seth B.,Crawford, Jason M.
, (2019/09/16)
Colibactin is a complex secondary metabolite produced by some genotoxic gut Escherichia coli strains. The presence of colibactin-producing bacteria correlates with the frequency and severity of colorectal cancer in humans. However, because colibactin has not been isolated or structurally characterized, studying the physiological effects of colibactin-producing bacteria in the human gut has been difficult. We used a combination of genetics, isotope labeling, tandem mass spectrometry, and chemical synthesis to deduce the structure of colibactin. Our structural assignment accounts for all known biosynthetic and cell biology data and suggests roles for the final unaccounted enzymes in the colibactin gene cluster.
Development of a practical and scalable route for the preparation of the deacetoxytubuvaline (dTuv) fragment of pretubulysin and analogs
Brindisi, Margherita,Maramai, Samuele,Grillo, Alessandro,Brogi, Simone,Butini, Stefania,Novellino, Ettore,Campiani, Giuseppe,Gemma, Sandra
supporting information, p. 920 - 923 (2016/02/05)
We present herein a novel and convenient route for the scaling-up of the dTuv fragment of pretubulysin. The newly conceived chemical path involves a practical and efficient one-step procedure for the preparation of a key thiazole intermediate, followed by high-yielding Wittig olefination/reduction steps. The optimized route, starting from the inexpensive and non-toxic l-cysteine, encompasses five synthetic steps and only two chromatographic purifications, thus displaying a dramatically increased overall yield. The versatility of the proposed approach also provides new hints for the exploration of pretubulysin derivatives bearing diverse heterocyclic portions.
Asymmetric aldol reaction of thiazole-carbaldehydes: Regio- And stereoselective synthesis of tubuvalin analogues
Paladhi, Sushovan,Das, Joydeb,Samanta, Mousumi,Dash, Jyotirmayee
supporting information, p. 3370 - 3376 (2015/02/02)
The first organocatalytic enantioselective approach to precursors of tubuvaline (pre-Tuv) is presented employing a prolinamide-catalyzed aldol reaction of easily accessible thiazole-carbaldehyde with methyl isopropyl ketone "on water" in excellent yield as well as regio- and enantioselectivities. The analogues of pre-Tuv were achieved using an l-proline-catalyzed direct asymmetric aldol reaction of substituted thiazole-carbaldehydes with acetone. A direct and flexible approach to the tubavaline (Tuv) core of tubusylins has been established employing the reductive amination of the pre-Tuv species. The key aldol reaction should greatly expand the potential of this strategy to the synthesis of natural product tubulysins and a range of analogues.
Total synthesis and complete structural assignment of thiocillin i
Aulakh, Virender S.,Ciufolini, Marco A.
scheme or table, p. 5900 - 5904 (2011/06/10)
The total synthesis of the thiopeptide antibiotic, thiocillin I, is described. This work unequivocally defines the full structure (constitution and configuration) of the natural product as 1.
An improved synthesis of pyridine-thiazole cores of thiopeptide antibiotics
Aulakh, Virender S.,Ciufolini, Marco A.
supporting information; experimental part, p. 5750 - 5753 (2009/12/06)
(Figure Presented) The oxidation of 2-methylthiazoles to 2-formylthiazoles simplifies the implementation of the Bagley variant of the Bohlmann-Rahtz reaction as a key step in a concise new route to pyridine cores of thiopeptide antibiotics.
