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K. C. Nicolaou Dionisios Vourloumis Tianhu Li Joaquin Pastor Nicolas Winssinger Yun He Sacha Ninkovic Francisco Sarabia Hans Vallberg Frank Roschangar N. Paul King M. Ray V. Finlay Pareskevi Giannakakou Pascal Verdier-Pinard Ernest Hamel 《Angewandte Chemie (International ed. in English)》1997,36(19):2097-2103
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Nicolaou KC Montagnon T Vassilikogiannakis G Mathison CJ 《Journal of the American Chemical Society》2005,127(24):8872-8888
Members of the coleophomone family of natural products all possess several intriguing and challenging architectural features, as well as exhibit unusual biological activity. They, therefore, constitute attractive targets for synthesis. In this Article, we describe the total synthesis of coleophomones B (2), C (3), and D (4). The highly strained and congested 11-membered macrocycle of coleophomones B (2) and C (3) was constructed using an impressive olefin metathesis reaction. Furthermore, both of the requisite geometric isomers of the Delta(16,17) within the macrocycle could be accessed from a common precursor, facilitating a divergence that lent the coleophomone B (2)/C (3) synthesis an unusually high degree of efficiency. The synthesis of coleophomone D (4) confirmed that it exists as a dynamic mixture of isomeric forms with a different aromatic substitution pattern from the other family members. 相似文献
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Nicolaou KC Cho SY Hughes R Winssinger N Smethurst C Labischinski H Endermann R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(17):3798-3823
Vancomycin, the prototypical member of the glycopeptide family of antibiotics, is a clinically used antibiotic employed against a variety of drug-resistant bacterial strains including methicillin-resistant Staphylococcus aureus (MRSA). The recent emergence of vancomycin resistance, viewed as a growing threat to public health, prompted us to initiate a program aimed at restoring the potency of this important antibiotic through chemical manipulation of the vancomycin structure. Herein, we describe the development of synthetic technology based on the design of a novel selenium safety catch linker, application of this technology to a solid-phase semisynthesis of vancomycin, and the solid- and solution-phase synthesis of vancomycin libraries. Biological evaluation of these compound libraries led to the identification of a number of in vitro highly potent antibacterial agents effective against vancomycin-resistant bacteria. In addition to aiding these investigations, the solid-phase chemistry described herein is expected to enhance the power of combinatorial chemistry and facilitate chemical biology and medicinal chemistry studies. 相似文献