Indoles Indolizidine

There is no uniform classification for the A. In the literature divisions according to origin (examples Aconitum, Amaryllidaceae, Aspidosperma, cactus, Catharanthus, Cephalotaxus, Cinchona, coca, Corydalis, curare, Dendrobates, ergot, Erythrina, Iboga, Lycopodium, Maytenus, opium, Rauvol-fia, Senecio, Strychnos, tobacco, Vinca alkaloids, salamander, Solanum, Veratrum steroid alkaloids) in addition to divisions according to chemical structure (examples aporphine, benzylisoquinoline, bis-benzylisoquinoline, berberine, carboline, diterpene, inudazole, indole, indolizidine, isoquinoline, lupinane, macrocyclic, morphine, peptide, / -phenyl-ethylamine, piperidine, purine, pyridine, pyrrolidine, pyrrolizidine, quinoline, quinolizidine, quinucli-dine, spermine, spermidine, steroid, terpene, tro-pane, tropolone alkaloids) are used. 

By employing intramolecular 1,3-dipolar cycloadditions, syntheses of pyrrolo-, pyrido[l,2-a]indol (140),a pyrrolizidine and indolizidine (140b) derivatives have been reported (Scheme 2.216). 

Iminium ion-vinylsilane cyclizations closely related to the one described here have been used to prepare indolizidine alkaloids of the pumiliotoxin A and elaeokanine families, indole alkaloids, amaryllidaceae alkaloids, and the antibiotic (+)-streptazolin. The ability of the silicon substituent to control the position, and in some cases stereochemistry, of the unsaturation in the product heterocycle was a key feature of each of these syntheses. 

Mar. ALKAL. 3-alkylpyridine, azirine, azacyclodecanes, p-carboline, C, or C22 bromopyrrole, guanidine, halotyrosine, (bis)imidazole, (bis)indole, imidazoiyi pyrroloazBpine, indolizidine, pept. alkal., pyridazine. high high... 

Indole is a heteroaromatic compound consisting of a fused benzene and pyrrole ring, specifically benzo [ pyrrole. The systematic name, lff-indole (1) distinguishes it from the less stable tautomer 3ff-indole [271-26-1] (2). Iff- Indole [120-72-9] is also more stable than the isomeric benzo[c] pyrrole, which is called isoindole, (2ff, (3) and Iff (4)). A third isomer benzo[i ]pyrrole is a stable compound called indolizidine [274-40-8] (5). 

Several (A/-alkenyl)iodoacetamides undergo cyclization when they are reacted with tetrakis(triphe-nylphosphine)palladium(O). The highest yields (which are generally only moderate) are obtained in DMF solution with 1,8-dimethylaminonaphthalene (Proton Sponge) to take up the hydrogen iodide formed. This reaction has been used to prepare piperidones, oxindoles, indolizidines, quinolizidines, pyrrolidines, indoles, quinolines53 and pyrrolizidines (equation 18).54... 

The Aspidosperma family of indole alkaloids has inspired many synthetic strategies for the construction of their pentacyclic framework of the parent compound aspidospermidine (366), since the initial clinical success of two derivatives, vinblastine (10) and vincristine, as anticancer agents. The alkaloids such as (-)-rhazinal (369) and (-)-rhazinilam (6) have been identified as novel leads for the development of new generation anticancer agents [10,11]. Bis-lactams (-)-leucunolam (370) and (-t-)-epi-leucunolam (371) have bio-genetic and structural relationships with these compounds [236]. Recently, enantioselective or racemic total syntheses of some of the these natural product were achieved. One successful synthesis was the preparation of the tricyclic ketone 365, an advanced intermediate in the synthesis of aspidospermidine (366), from pyrrole (1) (Scheme 76) [14]. The key step is the construction of the indolizidine 360, which represents the first example of the equivalent intramolecular Michael addition process [14,237,238]. The DIBAL-H mediated reduction product was subject to mesylation under the Crossland-... 

Benzindolizidine systems 963 are generated in moderate yields by a hexabutylditin-mediated consecutive radical addition, cyclization, and oxidation process from easily accessible l-(2-iodoethyl)indoles 962 and methyl acrylate, in one step (Scheme 186) <2000TL10181>. l-(2-Iodoethyl)-l//-pyrrole-2-carbaldehyde was also subjected to the tandem radical addition-cyclization process, and the indolizidine derivative 964 was isolated in modest yield as the major product together with a small amount of starting material (Equation 229). 

Imidazole alkaloids, 263 Indole alkaloids, 257-263 dehydrobufotenine, 262 dimeric, 261 indole amines, 261-262 pseudophrynamines, 257-261 trypargine, 262-263 Indole amines, 261-262 Indolizidines... 

Gercideae. (a) The occurrence of alkaloids. Key to branches leading to families that accumulate quinolizidines, pyrrolizidines (No. 1 see arrows) Erythrina (No. 3) indolizidines (No. 4) p-carbolines (No. 5) or simple indoles (No. 2) are marked. The rbcl sequences used (1400 bp) derived from Kass and Wink, 1997a,b Wink and Mohamed (2003). Trees were reconstructed with maximum parsimony. 

The majority of published work on aza-ylides concerns their applications in synthesis, and here we report a selection of contributions from this area. The Staudinger reaction is a popular route to aza-ylides and has been used to prepare a series of perfluoroalkyl-tagged aza-Wittig reagents, e.g., (68), which were generated in situ (Scheme 22), and utilised in the synthesis of 3//-quinazolidine-4-ones in a fluorous biphasic system. A method for the preparation of aza-polycyclic compounds derived from pyrrolidine, indolizidine and indole has... 

A range of alkaloids including isoquinoline, indolizidine, benzazepine, oxazine, quinoline and indole alkaloids were examined as potential inhibitors of eukaryote protein kinases such as PKC, MLCK and PKA. Only three oxazine alkaloids and four isoquinoline-based alkaloids and inhibitors of the protein kinases tested. A narrow structural and protein kinase target specificity, was observed. (+)-Boldine (39) and bulbocapnine (40) are specific for MLCK, while apomorphine (41) and sanguinarine (42) are for PKA. 

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