Tetracyclic alkaloid

Sasaki, M., Tsuda, M., Sekiguchi, M., Mikami, Y. and Kobayashi, J. 2005. Peri-nadine A, a novel tetracyclic alkaloid from marine-derived fungus Penicillium citrinum. Organic Letters, 1 4261 264. 

Terpenoid tetrahydroisoquinoline alkaloids 110 Terretonin 41, 56 Territrem A 43, 56 Territrem B 43, 56 Tetracyclic alkaloids 88, 100 Tetracyclic quinolizidine alkaloids 100, 101 Tetrahydroharman 59 Tetrahydroharmine 80, 112, 114 Tetrahydroisoquinoline alkaloids 7, 58, 68, 77, 78... 

VII. Tetracyclic Alkaloids of the Leontidine Group (Quinolizidine-Indolizidine Alkaloids)... 

The tetracyclic alkaloid quinine 1 and the diastereomeric alkaloid quinidine 2 share a storied history. Eric Jacobsen of Harvard recently completed (J. Am. Chem. Soc. 2004, 126, 706) syntheses of enantiomerically-pure 1 and of 2. For each synthesis, the key reaction for establishing the asymmetry of the target molecule was the enantioselective conjugate addition developed by the Jacobsen group. 

Phenanthridine and Related Alkaloids Narciclasine Related Alkaloids Dibenzo[c,e]azocine Alkaloids —Tetracyclic Alkaloids... 

Shigemori, H., Bae, M. A., Yazawa, K, Sasaki, T., and Kobayashi, J., Alteramide A, a new tetracyclic alkaloid from a bacterium Alteromonas sp. associated with the marine sponge Halichondria okadai, J. Org. Chem., 57, 4317, 1992. 

The absolute configuration of the unusual tetracyclic alkaloid tsukushinamine-A (10) (cf. Vol. 10, p. 69) has been established by X-ray crystallography.14... 

Lycopodium alkaloids. The Lycopodium (or club moss) alkaloids include quino-lizidine alkaloids in which N atoms are variously shared between two or three six-membered rings. The toxic alkaloid lycopodine (C5N G5N G6 [isobutyl<]) is a tetracyclic alkaloid with an N shared between two six-membered rings. The toxic alkaloid carolinianine (C5N C5N ]] C5N N CN5 )) is a tetracyclic with two Ns shared between three and two six-membered rings, respectively. Other such alkaloids, such as lycodine (G5N C6[isobutyl<] ] C5N), have Ns that are associated with only one ring. 

The intramolecular Michael addition of (—(-pyrrole 149 to give compound (—)-150, an intermediate in the asymmetric synthesis of an unique cytotoxic tetracyclic alkaloid (—)-Agelastatin A, was effected using CS2CO3 (Equation 27) <1998JOC7594, 1999JA9574, 2006ARK120>. 

Optical Resolution of Indole Alkaloid Precursors. This reagent has been used for optical resolutions of tetracyclic alkaloids such as 10,22-dioxokopsane (1) and kopsinine (2). ... 

The scope of this process has been extended in a more detailed investigation to the synthesis of quinolizines [175] and the influence of alkyl substituents in various positions of the aminodialkene substrate on product diastereoselectivity was probed. Neodymium-based catalysts are particularly efficient for six-membered ring formation (40). The methodology has found further application in the synthesis of tri- and tetracyclic alkaloidal skeletons (41) [176]. 

C. Tricyclic and Tetracyclic Alkaloids.—The chemical ionisation (C.I.) mass spectra of several quinolizidine alkaloids in the presence of methane as reactant gas have been studied the alkaloids concerned include a-isosparteine, lupanine,... 

A Occurrence, and Isolation of New Alkaloids B Bicyclic Alkaloids C Tricyclic and Tetracyclic Alkaloids... 

L1210 cells and epidermoid carcinoma KB cells was also observed for other cystodytins (91JNP1634). A bromo-substituted tetracyclic alkaloid pantherinine 138 has been isolated from the ascidian pantherinum,... 

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