Carboline synthesis

Bisehler-Napieralski reaetions, 4, 279 carboline synthesis from, 4, 516 Mannieh-type reactions, 4, 279 sulfur isosteres, biological activity, 4, 913 synthesis, 4, 337, 913 Tryptophan... 

The Bischler-Napieralski approach to /J-carboline synthesis is very similar to the Pictet-Spengler one, except that the tryptamine derivative is first... 

Qudguiner made great use of Suzuki methodology to prepare heterobiaryls for use in carboline synthesis [163]. This chemistry is discussed in Chapter 4. As explored in more detail in Section... 

Indole oximes are widely used in the synthesis of a-, /3- and y-carbolines. Synthesis of a-carbolines 302 was easily realized from 0-2,4-dinitrophenyl-substituted oximes 301... 

In a modified Graebe-Ullman reaction, pyridylbenzotriazole 223 was converted to a-carboline 224 in an efficient manner but in moderate yield (Scheme 38) <20060L415>. Microwave irradiation was the energy source for both a-carboline synthesis and the preparation of 223. The advantages of this procedure are that the starting materials are commercially available and lower reaction times are used resulting in fewer undesirable side products. The style of microwave oven, amount of pyrophosphoric acid, power level, and time were all optimized. 

Carboline synthesis. The 3-amino-4-(o-bromophenyl)pyridine 1 cyclizes to the (3-carboline 2 in the presence of tetrakis(triphenylphosphine)palladium(0) (1.2-1.5 equiv.,... 

P. H. Hermkens, W-Hydroxy-j3-carbolines Synthesis. Applications, and Biological Activities. Thesis of investigations carried out under Prof. H. C. J. Ottenheijm. University of Nijmegen, Nijmegen, The Netherlands, 1990. 

Queguiner made great use of Suzuki methodology to prepare heterobiaryls for use in carboline synthesis [169]. This chemistry is discussed in Chapter 4. As explored in more detail in Section 3.5, Grigg developed several Pd-catalyzed tandem cyclization-anion capture processes, and these include organoboron anion transfer agents [109, 170, 171], Two examples of this methodology are shown. 

Scheme 51. Pd-catalyzed intramolecular C-N bond formation in a-carboline synthesis...

Pyrido[2,3-h]indoles (a-carbolines), synthesis and reactivity of 84KGS435. 

Pyrido[2,3-h]indoles (a-carbolines), synthesis and reactivity of 84KGS435. Pyrido[2,3-c]indoles (/S-carbolines), biochemistry of 83MIIO. Pyrido[3,2-c]indoles, tetrahydro- (tetrahydro-y-carbolines) 73KGS291. 3//-Pyrrolo[2,3-c]quinolines 78H(9) 1617. 

A one-pot y-carboline synthesis was carried out by MWI of 4-chloroazines 229 with benzotriazoles 230 in the absence of a solvent to give 231 within 7-10 min. Subsequent irradiation for 4-6 min in the presence of pyrophosphoric acid gave y-carboline 232 in 30-81% yields (Scheme 49). Under conventional heating at... 

Scheme 3 Early Applications of the Craebe-Ullmann Carbazole-Carboline Synthesis...

Scheme 8 Craebe-Ullmann Carboline Synthesis with Microwave Irradiation...

The aromatic ring version of the Mori-Ban-Heck indole synthesis can be called an aryl-Heck reaction. This palladium-catalyzed cyclization of o-halo diaryl amines has seen many applications in carbazole and carboline synthesis. 

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