Lycoplanine A, a C₁₆N Lycopodium Alkaloid with a 6/9/5 Tricyclic Skeleton from Lycopodium complanatum

Abstract

Lycoplanine A (1), a Lycopodium alkaloid with a 6/9/5 tricyclic ring skeleton fused with the γ-lactone ring and featuring an unusual 1-oxa-6-azaspiro[4.4]nonane moiety and an unprecedented 3-azabicyclo[6.3.1]dodecane unit, was isolated from the club moss Lycopodium complanatum. The structure and absolute configuration of 1 were identified by a combination of NMR spectroscopic analysis and single-crystal X-ray diffraction. Biological studies showed that 1 is a potent Ca3.1 T-type calcium channel (TTCC) inhibitor with an IC value of 6.06 μM.

Silver Catalyzed Decarbonylative [3 + 2] Cycloaddition of Cyclobutenediones and Formamides

“…N , O -Acetal/ketal represent an important architecture in bioactive natural and pharmaceutical products [ 1 , 2 , 3 ]. Typical structures such as aspidosperma alkaloid (-)-aspidophytine [ 4 , 5 ], lycopodium alkaloid lycoplanine A [ 6 ], indoline alkaloid rosibiline [ 7 ], and macrocyclic marine alkaloid ‘upenamide [ 8 , 9 ] are shown in Figure 1 . Besides, Tegafur [ 10 ] containing a hemiaminal ether skeleton is used as an anticancer reagent and indolinooxzolidines [ 11 ] are effective in molecular switching.…”

Lycoplanines B-D, Three Lycopodium Alkaloids from Lycopodium complanatum

“…In our continuing efforts to find biogenetically interesting and structurally unique LAs, we reported a LA, lycoplanine A, posessing an intriguing tricyclic (6/9/5) ring skeleton from L. complanatum [ 14 ]. Further chemical investigation of the extracts of this plant resulted in the isolation of three new LAs, lycoplanines B-D ( 1 – 3 ), along with three known compounds lycopodine ( 4 ), lycopodine N -oxide ( 5 ), and des- N -methyl- α -obscurine ( 6 ).…”

Rhynchines A–E: Cav3.1 Calcium Channel Blockers from Uncaria rhynchophylla

“…Ca v 3.1 belongs to a subfamily of T-type voltage-gated calcium channels (T-VGCCs) and is predominantly expressed in neurons and widely expressed in vascular smooth muscle, cardiac muscle, and endocrine tissues . Ca v 3.1 is encoded by the CACNA1G gene and participates in many important electrophysiological activities such as neuron excitation, neurotransmitter release, smooth muscle contraction, and cardiac pacing. , However, potent and highly selective inhibitors against Ca v 3.1 are still rare, especially those from natural products . Therefore, the discovery of new inhibitors against Ca v 3.1 is of great significance to treat neurological and cardiovascular diseases such as epilepsy, arrhythmia, neuropathic pain, and hypertension. − …”