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Five new trace alkaloids with fawcettimine-related structures (1-5), i.e., 6-hydroxyl-6,7-dehydrolycoflexine (1), 6-hydroxyl-6,7-dehydro-8-deoxy-13-dehydroserratinine (2), together with three known ones (6-8), were isolated from the club moss Lycopodium japonicum Thunb. Their structures were
Five new Lycopodium alkaloids (1-5) having the fawcettimine skeleton were isolated from Lycopodium serratum. The structures of the alkaloids were elucidated on the basis of spectroscopic analysis. Some alkaloids isolated in this and previous studies (1, 2, 5, and 10) were assayed for acetylcholine
An asymmetric total synthesis of lycopoclavamine-A (1), a structurally unique fawcettimine-type Lycopodium alkaloid, was achieved via a stereoselective Pauson-Khand reaction and a stereoselective conjugate addition to construct a quaternary carbon center at C-12.
Ever since the pioneering synthetic work reported by both Inubushi and Heathcock back in 1980s, the fawcettimine-type Lycopodium alkaloids have continuously served as a driving force for discoveries in organic synthesis. In this personal account, we summarized our recent synthetic efforts towards
The stereocontrolled synthesis of a new azaspirocycle precursor of the fawcettimine-type Lycopodium alkaloids is described. Our approach provides an efficient entry to the azaspirocycle via a cascade Wacker-allylation sequence followed by a highly stereoselective Claisen rearrangement. This
The fawcettimine-type Lycopodium alkaloids have garnered significant attention from synthetic organic chemists since the isolation of fawcettimine in 1959. Despite being targets of interest for over 50 years, most of the strategies employed in the syntheses of fawcettimine congeners have built upon
A shared story: Three fawcettimine- and serratinine-type Lycopodium alkaloids are prepared from a common tetracyclic spirodiketone intermediate in concise total syntheses. The intermediate was constructed by a remarkable biosynthesis-inspired transannular N-C bond formation to the spiro-configured
A unified strategy for total synthesis of the Lycopodium alkaloids (-)-8-deoxyserratinine (7), (+)-fawcettimine (1), and (+)-lycoflexine (4) is detailed. The key features include a highly efficient Helquist annulation to assemble the cis-fused 6/5 bicycle, facile construction of the aza
A new approach for synthesis of fawcettimine-type Lycopodium alkaloids is described. A divergent strategy was achieved by applying stereoselective Diels-Alder reaction followed by redox-controlled elaboration. Eventually, (-)-8-deoxyserratinine, (+)-fawcettimine, (-)-lycopoclavamine-A,
A successful asymmetric total synthesis of lycoposerramine-C involving such key steps as a cobalt-mediated Pauson-Khand reaction and vinyl Claisen rearrangement and its biomimetic transformation to phlegmariurine-A are described.
Four from one: The four title alkaloids (structures shown in blue box) have been synthesized by using a common versatile intermediate with a 6/5/5 tricyclic skeleton. This tricyclic intermediate could be easily assembled by using an intramolecular carbene addition/cyclization and a Dieckmann
Seven lycopodine-type (annotinolide F and lycoannotines A-F), two lycodine-type (lycoannotines G and H), and one fawcettimine-type (lycoannotine I) previously undescribed naturally occurring Lycopodium alkaloids together with thirteen known ones were isolated from the whole plant of Lycopodium
Chemical investigation on the crude alkaloid portion of Lycopodium obscurum led to isolation of three new fawcettimine-type Lycopodium alkaloids, lycobscurines A-C (1-3), together with three known compounds. Their structures were determined by spectroscopic methods including HR-ESI-MS and NMR
Seven new fawcettimine-type (1-7) and two new lycopodine-type (8 and 9) Lycopodium alkaloids, as well as 10 known compounds, were isolated from the club moss, Lycopodium obscurum L. The structures of obscurumines H-P (1-9) were determined based on high-resolution MS and 1D and 2D NMR data. Compounds