Author
Chunhua Yang
Bio: Chunhua Yang is an academic researcher from Merck & Co.. The author has contributed to research in topics: Hydroxymethyl & Furanose. The author has an hindex of 11, co-authored 35 publications receiving 729 citations.
Topics: Hydroxymethyl, Furanose, Amide, Chiral auxiliary, Protecting group
Papers
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181 citations
TL;DR: A novel method for palladium-catalyzed cyanation of aryl bromides promoted by low-level tri-n-butyltin chloride or cyanide is described, which features low catalyst loading and mild reaction conditions.
155 citations
TL;DR: A short synthesis of carbapenem 1 is described, which involves the cross-coupling of an enol triflate with an amino-substituted sp3 carbon and utilizes a stannatrane as the heteroalkyl transfer reagent.
67 citations
TL;DR: A practical, efficient synthesis of 1, a hepatitis C virus RNA replication inhibitor, is described, which features a novel stereoselective rearrangement to prepare the key crystalline furanose diol intermediate.
Abstract: A practical, efficient synthesis of 1, a hepatitis C virus RNA replication inhibitor, is described. Starting with the inexpensive diacetone glucose, the 12-step synthesis features a novel stereoselective rearrangement to prepare the key crystalline furanose diol intermediate. This is followed by a highly selective glycosidation to couple the C-2 branched furanose epoxide with deazapurine.
67 citations
TL;DR: A practical preparation of an alpha(v)beta(3) antagonist is reported, which consists of three key components, a tetrahydronaphthyridine moiety, a beta-alanine moieties, and a central imidazolidone moiety.
Abstract: A practical preparation of an αvβ3 antagonist is reported. The antagonist consists of three key components, a tetrahydronaphthyridine moiety, a β-alanine moiety, and a central imidazolidone moiety. The tetrahydronaphthyridine component was prepared using two different methods, both of which relied on variations of the Friedlander reaction to establish the desired regiochemistry. The β-alanine component was prepared using Davies' asymmetric 1,4-addition methodology as the key stereo-defining step. The central imidazolidone portion was created from these two components using an effective three-step cyclization protocol. Thus, a highly convergent process for the drug candidate was defined.
59 citations
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3,281 citations
TL;DR: This Review attempts to trace the historical origin of these powerful reactions, and outline the developments from the seminal discoveries leading to their eminent position as appreciated and applied today.
Abstract: In 2010, Richard Heck, Ei-ichi Negishi, and Akira Suzuki joined the prestigious circle of Nobel Laureate chemists for their roles in discovering and developing highly practical methodologies for C-C bond construction. From their original contributions in the early 1970s the landscape of the strategies and methods of organic synthesis irreversibly changed for the modern chemist, both in academia and in industry. In this Review, we attempt to trace the historical origin of these powerful reactions, and outline the developments from the seminal discoveries leading to their eminent position as appreciated and applied today.
2,148 citations
1,368 citations
TL;DR: In this review different examples from 2001-2008 are highlighted, which have been performed at least on a kilogram scale in the chemical and pharmaceutical industries.
Abstract: Palladium-catalyzed coupling reactions have become a central tool for the synthesis of biologically active compounds both in academia and industry. Most of these transformations make use of easily available substrates and allow for a shorter and more selective preparation of substituted arenes and heteroarenes compared to non-catalytic pathways. Notably, molecular-defined palladium catalysts offer high chemoselectivity and broad functional group tolerance. Considering these advantages, it is not surprising that several palladium-catalyzed coupling reactions have been implemented in the last decade into the industrial manufacture of pharmaceuticals and fine chemicals. In this review different examples from 2001-2008 are highlighted, which have been performed at least on a kilogram scale in the chemical and pharmaceutical industries.
1,121 citations
TL;DR: This review analyses the seven main classes of boron reagent and evaluates the general physical and chemical properties of each class with special emphasis on the currently understood mechanisms of transmetalation.
Abstract: Suzuki–Miyaura (SM) cross-coupling is arguably the most widely-applied transition metal catalysed carbon–carbon bond forming reaction to date. Its success originates from a combination of exceptionally mild and functional group tolerant reaction conditions, with a relatively stable, readily prepared and generally environmentally benign organoboron reagent. A variety of such reagents have been developed for the process, with properties that have been tailored for application under specific SM coupling conditions. This review analyses the seven main classes of boron reagent that have been developed. The general physical and chemical properties of each class of reagent are evaluated with special emphasis on the currently understood mechanisms of transmetalation. The methods to prepare each reagent are outlined, followed by example applications in SM coupling.
989 citations