52643-52-4Relevant academic research and scientific papers
Bioinspired Total Synthesis of Bussealin e
Twigg, David G.,Baldassarre, Leonardo,Frye, Elizabeth C.,Galloway, Warren R. J. D.,Spring, David R.
, p. 1597 - 1599 (2018/03/23)
The first total synthesis of bussealin E, a natural product with a unique cycloheptadibenzofuran scaffold, is reported. A strategy inspired by a proposed biosynthesis was employed whereby a diphenylpropane derivative underwent an oxidative phenolic coupling to forge the tetracyclic ring system. The synthesis of the diphenylpropane featured a key sp2-sp3 Hiyama coupling between a vinyldisiloxane and a benzylic bromide.
Helical-Shaped Bis-1,4-benzoxathiines through an Inverse-Electron-Demand Hetero-Diels–Alder Reaction of ortho-Thioquinones
Viglianisi, Caterina,Menichetti, Stefano,Piantini, Sara,Tofani, Lorenzo
, p. 5386 - 5392 (2016/11/22)
The reaction of transient ortho-thioquinones, which act as electron-poor dienes, with properly designed bis-dienophiles leads to the formation of helical-shaped bis-benzoxathiine cycloadducts with complete control of the regiochemistry and the relative stereochemistry. Bis-benzoxathiines were the result of two consecutive inverse-electron-demand cycloaddition processes with stereospecific approach of the diene anti to the bis-dienophile. The helical-shaped structure of the final products was demonstrated spectroscopically and confirmed by single-crystal X-ray analysis.
Synthesis of an Isotopically Labeled Naphthalene Derivative That Supports a Long-Lived Nuclear Singlet State
Hill-Cousins, Joseph T.,Pop, Ionut-Alexandru,Pileio, Giuseppe,Stevanato, Gabriele,H?kansson, P?r,Roy, Soumya S.,Levitt, Malcolm H.,Brown, Lynda J.,Brown, Richard C. D.
supporting information, p. 2150 - 2153 (2015/05/13)
The synthesis of an octa-alkoxy substituted isotopically labeled naphthalene derivative, shown to have excellent properties in singlet NMR experiments, is described. This highly substituted naphthalene system, which incorporates an adjacent 13C spin pair, is readily accessed from a commercially available 13C2-labeled building block via sequential thermal alkynyl- and arylcyclobutenone rearrangements. The synthetic route incorporates a simple desymmetrization approach leading to a small difference in the chemical shifts of the 13C spin pair, a design constraint crucial for accessing nuclear singlet order. (Chemical Equation Presented).
Anti-tumor agents
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, (2008/06/13)
The invention concerns anti-tumor agents of formula (I), wherein each of R1, R2and R3has the meanings defined in the specification including hydrogen, (1-4C)alkyl, (3-4C)alkynyl and (1-4C)alkoxyl; each of R4and
Anti-tumuor agents
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Page column 24, (2010/01/30)
The invention concerns anti-tumour agents of formula (I) wherein each of R1, R2and R3has the meanings defined in the specification including hydrogen, (1-4C)alkyl, (3-4)alkenyl, (3-4C)alkynyl, amino, (1-4C)alkylamino and (
Electronic Control of Stereoselectivity. 9. The Stereochemical Course of Electrophilic Additions to Aryl-Substituted Benzobicyclooctadienes
Paquette, Leo A.,Bellamy, Francois,Wells, Gregory J.,Boehm, Michael C.,Gleiter, Rolf
, p. 7122 - 7133 (2007/10/02)
Product and relative reactivity data have been obtained for the photooxygenation, epoxidation, cyclopropanation, oxymercuration, and hydroboration of three differently substituted (aryl) 2-methylbenzobicyclooctadienes.Syn stereoselectivity was observed in every case, with the level of syn attack being highest with the tetrafluoro derivative 2c (except in the Simmons-Smith reaction where a single isomer was produced in every case).Only small differences in rate were seen with a given reagent.Electronic interactions in these molecules were explored by photoelectron spectroscopy and MINDO/3 calculations.These combined tools served to show that through-space interaction is absent in these molecules.However, through-bond coupling in 2a and 2b leads to olefinic ?-bond disrotation.The relative importance of this effect as well as long-range Coulomb and charge-transfer interactions is discussed.A connection between such subtle electronic influences and stereoselectivity is established, although prevailing steric effects do serve to compress somewhat the syn/anti range available to these systems.
