Amaryllidacae alkaloids

Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis

“…Recent work by Minter and Winslow involves the use of an unusual De Mayo approach for constructing the tetracyclic galanthan ring system ( 296 , Figure ), which is the core of the lycorine-type Amaryllidaceae alkaloids. , Minter and Winslow utilized photosubstrate 305 , synthesized in three steps from isocarbostyril ( 300 ), as the precursor to the galanthan skeleton. Irradiation of the De Mayo substrate 305 afforded a single product, which was shown to be photoproduct 307 with the correct cis stereochemistry of the vicinal tertiary ring protons.…”

Chapter 3 Chemical and Biological Aspects of Narcissus Alkaloids

“…The history of the Amaryllidaceae alkaloids, their structural elucidation, and their biological profiles, as well as their synthesis, have been summarized on several occasions (20,33,(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48) which, together with the regular publications in the journal Natural Product Reports (34,(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60)(61)(62)(63)(64)(65)(66), represent a valuable source of information.…”

Anionic Cycloaromatization of 1-Aryl-3-hexen-1,5-diynes Initiated by Methoxide Addition: Synthesis of Phenanthridinones, Benzo[c]phenanthridinones, and Biaryls

“…Although the chemical yields are low, this reaction constitutes a novel cycloaromatization of enediynes and a new synthetic approach to phenanthridinones and biphenyls. Since phenanthridinones, biphenyls, and structurally related compounds are of current interest in the pharmaceutical area and for the preparation of new materials, methods for the selective preparation of these compounds have considerable synthetic value. A proposed mechanism for the formation of phenanthridinones is methoxide addition to the cyano group, followed by an anionic cascade cycloaromatization.…”