- Synthesis of 1,2-Dihydroisoquinolines by a Modified Pomeranz-Fritsch Cyclization
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Isoquinolines (IQs) and their derivatives are present in many natural products and biologically active small molecules. Herein, we report a modified procedure for the classical Pomeranz-Fritsch protocol, which expands the scope of 1,2-dihydroisoquinoline (DHIQ) products. 1,2-DHIQs are an attractive branch point for the synthesis of IQs, but because of their innate reactivity, they have remained difficult to prepare. We demonstrate that the Fujioka/Kita conditions, combining trimethylsiyltriflate (TMSOTf) and an amine base, activate dimethylacetals required for Pomeranz-Fritsch cyclization under sufficiently mild conditions to prepare a broad range of 1,2-DHIQ products. We also demonstrate the synthetic value of these DHIQs by further functionalization to either reduced tetrahydroisoquinoline (THIQ) or fully aromatized IQ natural products.
- Ji, Xiang,Huang, Zheng,Lumb, Jean-Philip
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p. 1062 - 1072
(2020/01/31)
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- Synthesis of Indenoisoquinoliniums and Methods of Use
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Substituted indenoisoquinolinium compounds, and pharmaceutical formulations of substituted indenoisoquinolinium compounds are described. Also described are processes for preparing substituted indenoisoquinolinium compounds. Also described are methods for
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Page/Page column 11-12
(2008/12/07)
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- Synthesis and mechanism of action studies of a series of norindenoisoquinoline topoisomerase I poisons reveal an inhibitor with a flipped orientation in the ternary DNA-enzyme-inhibitor complex as determined by X-ray crystallographic analysis
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Several norindenoisoquinolines substituted with methoxy or methylenedioxy groups have been prepared and their anticancer properties evaluated in cancer cell cultures and in topoisomerase I inhibition assays. 2,3-Dimethoxy-8,9- methylenedioxy-11H-indeno[1,
- Ioanoviciu, Alexandra,Antony, Smitha,Pommier, Yves,Staker, Bart L.,Stewart, Lance,Cushman, Mark
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p. 4803 - 4814
(2007/10/03)
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- Preparation of N-benzylsulfonamido-1,2-dihydroisoquinolines and their reaction with Raney nickel. A mild, new synthesis of isoquinolines
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N-benzylsulfonamido-1,2-dihydroisoquinolines react with Raney nickel to provide isoquinotines in excellent yields and under mild, neutral conditions.
- Larghi, Enrique L.,Kaufman, Teodoro S.
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p. 3159 - 3162
(2007/10/03)
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- Studies Directed Towards Total Syntheses of the Tropoloisoquinoline Alkaloids Grandirubrine and Imerubrine. I. Preparation of Two 4,5,6-Trimethoxycyclopentisoquinolin-7-ones and Their Response to Robinson Annulation Conditions
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In connection with efforts to develop total syntheses of the tropoloisoquinoline alkaloids grandirubrine (1) and imerubrine (2), preparations of tricyclic ketone (8) and the related ethoxycarbonyl system (47) are described.Of the various approaches to (8)
- Banwell, Martin G.,Bonadio, Anna,Turner, Kathleen A.,Ireland, Neil K.,Mackay, Maureen F.
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p. 325 - 351
(2007/10/02)
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