Carbazoles 3-Carboline alkaloids

A. Simple indoles, carbazoles, carbolines, and physostygmine type alkaloids 106... 

Of the more than 4500 known naturally occurring organohalogen compounds, a large fraction are alkaloids [1,3]. Most of these halogenated pyrroles, indoles, carbazoles, carbolines, tyrosines, and others have a marine origin. The present chapter surveys the occurrence, structure, and biosynthesis of these fascinating natural products. However, given their sheer number, this review focuses mainly on recent examples. 

Jia [11] and Driver [12] both discovered a Ru-catalyzed intramolecular amination of aryl azides to give indoles, carbazoles, and carbolines (Scheme 2, eqnations 1 and 2), including a synthesis of the y-carboline alkaloid dimebolin... 

Carboline and Carbazole-Derived Alkaloids 7.8.1 Annomontine and Related Pyrimidine-fi-Carbolines... 

Husson, H. Simple Indole Alkaloids Including p-Carbolines and Carbazoles In Alkaloids, Vol. 26, pp. 1 (Arnold Brossi Ed.) New York Academic Press. 1985. 

Nonami, H. Fukui, S. Erra-Balsells, R. P-Carboline alkaloids as matrices for matrix-assisted ultraviolet laser desorption time-of-flight mass spectrometry of proteins and sulfated oligosaccharides a comparative study using phenylcarbonyl compounds, carbazoles and classical matrices. J. Mass Spectrom. 1997, 32, 287 296. 

Malbrancheamide (60) represents a novel type of CaM inhibitors although other natural indole alkaloids such as the unusual indole-carbazole alkaloids from a culture broth of a Nocardiopsis sp, namely K-252a-K252d, the brominated P-carbolines eudistomidins A and C, obtained... 

A 6-cyano-5-methoxy-12-methylindolo[2,3-a]carbazole and 6-cyano-5-methoxyindolo[3-a]carbazole were isolated from the blue-green alga Nostoc sphaericum [95]. These compounds are active against HSV-1. Larsen ct al. [96] isolated three new chlorine-containing P-carbolines, bauerines A-C, from the blue-green alga Dichothrix baueriana. These alkaloids show activity against HSV-2. 

Several investigators have developed the reductive cyclization of o-nitrostyrenes into an efficient synthesis of indoles. Thus, research by the groups of Watanabe [480], Soderberg [481], and Cenini [482] have established this reductive Pd-catalyzed TV-het-eroannulation reaction as a viable and powerful route to simple indoles and fused indoles (411) as shown below. In addition, Soderberg has shown the application of this method to carbazolones [481d], natural p-carbolines [481e], and the carbazole alkaloid murrayaquinone A [48If]. Ohta described the related Pd-catalyzed cyclization of o-aminophenethyl alcohol to indole in 78% yield [483]. 

Husson, H., Simple indole alkaloids including 3-carbolines and carbazoles, in The Alkaloids, Vol. 26 (A. Brossi, ed.), 1-53, Academic Press, 1985. 

The intramolecular amine-halogen copper-promoted indohzation was applied to the synthesis of more-complex indoles (Scheme , equations 1 ) [58-61]. Other examples in this category of copper-catalyzed amination are syntheses of the carbazole alkaloids murrayaquinone-A and ( )-bis-murrayaquinone-A [62], 3-aryl p-carbolin-l-ones [63, 64], carbazoles from donble C-N cyclization [65], pyrrolo[2,3-c]... 

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