685895-45-8Relevant academic research and scientific papers
Azaphilones as Activation-Free Primary-Amine-Specific Bioconjugation Reagents for Peptides, Proteins and Lipids
Wang, Huan,Wei, Siyuan,Wu, Qingsong,Yao, Zhu-Jun,Yi, Shandong
, (2021/12/24)
Residue-selective bioconjugation methods for biomolecules are highly sought to expand the scope of their biological and medical applications. Inspired by the mechanism of the generation of natural vinylogous γ-pyridones (vPDNs), we have developed a novel
Bioinspired Total Synthesis of (±)-Chaetophenol C Enabled by a Pd-Catalyzed Cascade Cyclization
Li, Yun,Zhang, Qingyu,Wang, Hongyu,Cheng, Bin,Zhai, Hongbin
supporting information, p. 4387 - 4390 (2017/08/23)
A novel Pd(II)-catalyzed cascade reaction has been developed that consists of a highly regio- and stereoselective oxa [4 + 2] cycloaddition reaction of o-alkynylbenzaldehydes and an intramolecular carboxylic group quenching of the in situ generated oxonium ion. This new reaction provides a one-step construction of the tetracyclic core structure of chaetophenol C from two simple starting materials. The developed chemistry was successfully applied to the first total synthesis of chaetophenol C and dozens of its analogues.
Total synthesis of chlorofusin, its seven chromophore diastereomers, and key partial structures
Clark, Ryan C.,Sang, Yeul Lee,Boger, Dale L.
supporting information; experimental part, p. 12355 - 12369 (2009/02/05)
Chlorofusin is a recently isolated, naturally occurring inhibitor of p53-MDM2 complex formation whose structure is composed of a densely functionalized azaphilone-derived chromophore linked through the terminal amine of ornithine to a nine residue cyclic peptide. Herein we report the full details of the total synthesis of chlorofusin, resulting in the assignment of the absolute stereochemistry and reassignment of the relative stereochemistry of the complex chromophore. Condensation of each enantiomer of an azaphilone chromophore precursor with the Nδ-amine of a protected ornithine-threonine dipeptide, followed by a one-step oxidation/spirocyclization of the most reactive olefin provided all eight diastereomers of the fully elaborated chromophore-dipeptide conjugate. Comparison of the spectroscopic properties for these eight compounds and those of simpler models with that reported for the natural product allowed the full assignment of the (4R,8S,9R)-stereochemistry of the chlorofusin chromophore. The natural, but stereochemically reassigned, diastereomer of the dipeptide conjugate was incorporated in a convergent total synthesis of chlorofusin confirming the stereochemical reassignment and establishing its absolute stereochemistry. Similarly and enlisting the late stage convergent point in the total synthesis, the remaining seven diastereomers of the chromophore-dipeptide conjugates were individually incorporated into the nine-residue cyclic peptide of chlorofusin (4 steps each) providing all seven remaining possible chromophore diastereomers of the natural product.
Efficient construction of novel α-keto spiro ketal and the total synthesis of (±)-terreinol
Wei, Wan-Guo,Zhang, Yong-Xia,Yao, Zhu-Jun
, p. 11882 - 11886 (2007/10/03)
The first total synthesis of (±)-terreinol is described. An intramolecular Pd(II)-catalyzed cycloisomerization of a 2-(1′-alkynyl) benzyl alcohol via an apparent 6-endo diagonal pathway led to the 1H-isochromene ring system, which was further converted to
Synthesis of azaphilones and related molecules by employing cycloisomerization of o-alkynylbenzaldehydes
Zhu, Jianglong,Germain, Andrew R.,Porco Jr., John A.
, p. 1239 - 1243 (2007/10/03)
Right to the core: Gold(III)-catalyzed cycloisomerization of o-alkynylbenzaldehydes to 2-benzopyrylium salts and subsequent in situ oxidation have been employed to prepare the core structure of azaphilone natural products, such as the sphingosine kinase inhibitor S-15183 (see scheme, DCE = 1,2-dichloroethane, TFA = trifluoroacetic acid)), and several unnatural azaphilones.
