2202-79-1Relevant articles and documents
Oxidative dehydrogenation and the aromatization of polycycles using o-iodoxybenzoic acid (IBX)
Kotha, Sambasivarao,Banerjee, Shaibal,Mandal, Kalyaneswar
, p. 2043 - 2045 (2004)
An efficient and convenient method for the dehydrogenation and aromatization of various polycycles using o-iodoxybenzoic acid (IBX) is described.
Photosensitization of Fluorofuroxans and Its Application to the Development of Visible Light-Triggered Nitric Oxide Donor
Seymour, Christopher Peter,Tohda, Rei,Tsubaki, Motonari,Hayashi, Masahiko,Matsubara, Ryosuke
, p. 9647 - 9654 (2017)
Nitric oxide (NO) is an endogenous signaling molecule used in multiple biochemical processes. The development of switchable NO donors that deliver an NO payload under spatiotemporal control harbors many medicinal benefits. Previously, 4-fluorofuroxans were found to function as a UV light-induced NO donor under physiological conditions based on the photoinduced isomerization mechanism; however, the isomerization of fluorofuroxans with longer wavelength light is desired for further application into living systems. Herein, we report the use of photosensitizers in the photochemical isomerization of fluorofuroxan, enabling the use of visible light to induce isomerization. Among the tried photosensitizers, anthraquinone derivatives showed a good sensitizing ability to isomerize 4-fluorofuroxan to 3-fluorofuroxan using visible light. This new phenomenon was applied to the synthesis of a water-soluble anthraquinone-fluorofuroxan all-in-one molecule, which demonstrated promising NO-releasing ability using 400-500 nm irradiation. A high level of control is displayed with "on" and "off" NO-release functionality suggesting that photosensitizer-furoxan hybrids would make valuable donors. Furthermore, unlike most furoxans, NO is released in the absence of thiol cofactor.
Generation of Endocyclic Vinyl Carbene Complexes via Gold-Catalyzed Oxidative Cyclization of Terminal Diynes: Toward Naphthoquinones and Carbazolequinones
Shu, Chao,Shi, Chong-Yang,Sun, Qing,Zhou, Bo,Li, Tian-You,He, Qiao,Lu, Xin,Liu, Rai-Shung,Ye, Long-Wu
, p. 1019 - 1025 (2019/01/15)
Carbene cascade reactions involving carbene/alkyne metathesis have attracted much attention over the past decades because this chemistry offers great potential to build complicated cyclic molecules. However, the formed vinyl metal carbenoids in these reactions are limited to exocyclic carbenes, and the generation of endocyclic vinyl carbene complexes remains unexplored. Here, we report an unprecedented gold-catalyzed oxidative cyclization of terminal diynes. Importantly, the generation of endocyclic vinyl carbene complexes was involved in this oxidative cyclization, which is distinctively different from previous protocols. This method allows the facile synthesis of various valuable naphthoquinones and carbazolequinones from readily available diynes under exceptionally mild reaction conditions and features a broad substrate scope and wide functional group tolerance. Moreover, theoretical calculations provide further evidence on the divergent selectivity of this cyclization reaction.
Ruthenium-catalyzed C-H oxygenation of quinones by weak O-coordination for potent trypanocidal agents
Dias, Gleiston G.,Rogge, Torben,Kuniyil, Rositha,Jacob, Claus,Menna-Barreto, Rubem F. S.,Da Silva Júnior, Eufranio N.,Ackermann, Lutz
, p. 12840 - 12843 (2018/11/30)
Ruthenium-catalysis enabled the C-5 selective C-H oxygenation of naphthoquinones, and also sets the stage for the site-selective introduction of a hydroxyl group into anthraquinones. A-ring modified naphthoquinoidal compounds represent an important class of bioactive quinones for which the present study encompasses the first C-H oxygenation strategy by weak O-coordination.
