Indole alkaloids, miscellaneous

Miscellaneous Indole Alkaloids.—Echinulin (38) is known to be assembled from tryptophan, mevalonic acid, and alanine.24-26 The indole derivative (37) has now been shown27 to be converted efficiently by Aspergillus amstelodami into echinulin and is, therefore, probably an intermediate. 

In other miscellaneous indole alkaloid syntheses. Joule reported formal syntheses of the makaluvamines <97JOC568> while Lown has developed a new synthesis of the pyrroloquinone nucleus of these alkaloids <97SC2103>. Edstrom reported the synthesis of a fully functionalized 7-aminoaziridinomitosene <97T4549>, and two new approaches to the duocarmycins were reported <97JOC8868,97TL7207>. Finally, Knolker has utilized his iron-mediated construction of carbazoles in the first. synthesis of the antibiotic carbazomycins C and D <97JCS(P1)349>, as well as other carbazole natural products. 

Kopsine and aspidofractinine groups miscellaneous indole alkaloids... 

Miscellaneous - A number of unusual dimeric indole alkaloids Fave been studied and structures have been postulated primarily on the basis of interpretation of physical data The biological activities of these entities are presently unreported Plelcarpa pycnantha has yielded one such new... 

M. Miscellaneous Monomeric Indole and Oxindole Alkaloids 1. Macroxine-A... 

Miscellaneous Processes. A versatile synthetic route to the pyrrolophenanthridone alkaloids has been developed that involves a palladium-mediated cyclization of iV-benzoyl indolines, then 2,3-dichloro-5,6-dicyano- 1,4-benzoquinone (DDQ)-promoted oxidation of the resulting dihydropyrrolophenanthridones. Related processes have been exploited in an elegant total synthesis of the marine alkaloid (+)-dragmacidin F and in the preparation of biologically relevant indoles. 202.203... 

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