- Benzannulation of 2-Alkenylindoles using Aldehydes by Sequential Triple-Relay Catalysis: A Route to Carbazoles and Carbazole Alkaloids
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Benzannulation of 2-alkenylindoles with readily available aldehydes, under one-pot sequential triple-relay-catalysis, provides an easy access to several structurally unique carbazoles including 2- and 3-alkenylcarbazoles. This protecting group-free method enabled one-pot synthesis of alkaloids such as hyellazole and 6-chlorohyellazole, and the formal syntheses of seven other alkaloids. Construction of the core structure, present in murastifoline A, murrafoline E, and related alkaloids was also demonstrated. Even conjugated 3,3′-biscarbazoles can also be synthesized by one-pot, two-fold sequential triple-relay catalysis. (Figure presented.).
- Banerjee, Ankush,Sahu, Samrat,Maji, Modhu Sudan
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supporting information
p. 1860 - 1866
(2017/06/09)
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- First total synthesis of the whole series of the antiostatins A and B
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The first synthesis of the whole antiostatin family is described by using an iron-mediated carbazole synthesis, regioselective nitration at C-4 and establishing 5-isobutyl-1-nitrobiuret as a reagent for introduction of the antiostatin B side chain at C-4.
- Knott, Kerstin E.,Auschill, Stefan,J?ger, Anne,Kn?lker, Hans-Joachim
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scheme or table
p. 1467 - 1469
(2009/09/06)
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- Transition metal complexes in organic synthesis. Part 65: Iron-mediated synthesis of carazostatin, a free radical scavenger from Streptomyces chromofuscus, and O-methylcarazostatin
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Highly efficient syntheses of the free radical scavenger carazostatin and its O-methyl derivative are described using cyclohexa-1,3-diene and 2-heptyl-4-methoxy-3-methylaniline as starting materials and iron-mediated oxidative cyclizations as key-steps.
- Kn?lker, Hans-Joachim,Hopfmann, Thomas
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p. 8937 - 8945
(2007/10/03)
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- In vitro and ex vivo free radical scavenging activities of carazostatin, carbazomycin B and their derivatives
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Free radical scavenging activities of various carbazole compounds, carazostatin, carbazomycin B and their chemically modified derivatives were studied in vitro and ex vivo. Among these compounds, carazostatin, which was isolated as a free radical scavenger from the culture of Streptomyces chromofuscus, showed the most potent inhibitory activity against lipid peroxidation of rat brain homogenate in vitro. Carbazomycin B, a known antimicrobial antibiotic, also exhibited strong activity in this system. Although O-modified derivatives of carazostatin and carbazomycin B retained considerable activity, N,O-dimethyl derivatives did not suppress the peroxidation. On the other hand, the results from the ex vivo evaluation of these carbazoles in the lipid peroxidation system of mouse blood plasma showed that the original compounds as well as their O-modified derivatives had a strong inhibitory activity upon oral administration to mice. These findings suggest that these natural carbazoles and their effective derivatives can protect tissues from the peroxidative damage due to generation of free radicals.
- Kato,Kawasaki,Urata,Mochizuki
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p. 1859 - 1865
(2007/10/02)
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- Synthesis and Electrochemical Properties of the Naturally Occuring Free Radical Scavenger Carazostatin
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A short synthesis of the naturally occuring free radical scavenger carazostatin 1 starting from indol-3-ylacetic acid is described, the key step being the regiospecific Diels-Alder reaction of the indolopyrone 2 with ethyl trimethylsilylpropynoate.Electro
- Jackson, P. Mark,Moody, Christopher J.,Mortimer, Roger J.
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p. 2941 - 2944
(2007/10/02)
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