Phlegmacaritones A and B, a Pair of Serratane-Related Triterpenoid Epimers with an Unprecedented Carbon Skeleton from Phlegmariurus carinatus

Abstract

A pair of novel serratane-related triterpenoid epimers, phlegmacaritones A (1) and B (2), possessing an unprecedented 15,30lactone-14,15-seco skeleton, six new serratane-type triterpenoids, phlegmanols G−L (3−5 and 14−16), and 16 known compounds were isolated from the whole plant of Phlegmariurus carinatus. The structures of the new metabolites were established on the basis of comprehensive spectroscopic data analysis and electronic circular dichroism calculations. A possible biosynthetic pathway for phlegmacaritones A (1) and B (2) was proposed. All compounds were submitted to cytological profiling on a cell line derived from a patient with Parkinson's disease. Phlegmacaritone B (2) induced a distinct phenotypic profile with alterations in α-tubulin, mitochondria, and autophagosomal and early endosomal features.

Lycopodium Alkaloids from Phlegmariurus carinatus with Cytotoxic and Neuroprotective Effects

“…1 H-NMR spectrum (Table 1) of 1 exhibited the resonances for a methyl at δ H 1.66 (3H, s), an oxygenated methylene at δ H 3.79-3.85 (1H, m), and two olefinic protons at δ H 4.91 (1H, d, J = 2.0) and 5.54 (1H, s). The 13 2). [17] An electron-donating group was connected to C-15 (δ C The NOESY cross-peaks (Figure 2) of H-1b (δ H 3.10-3.12)/H-14, H-1b/ H-3b (δ H 1.27-1.34), H-3b/H-5 (δ H 3.79-3.85), and H-4 (δ H 1.72)/H-7 (δ H 2.52-2.58) indicated that H-4 and H-7 are cofacial with an αorientation and H-5 with an β-orientation.…”

“…The whole plant of P. Carinatus has long been used as a folk medicine for treating swelling, rheumatism, and pain [9,10] . Previous phytochemical studies on P. Carinatus identified a series of LAs and serratene triterpenes [11–14] . Some of these compounds showed various degrees of cytotoxic, anti‐AChE, and anti‐Parkinson's disease activities.…”

“…[9,10] Previous phytochemical studies on P. Carinatus identified a series of LAs and serratene triterpenes. [11][12][13][14] Some of these compounds showed various degrees of cytotoxic, anti-AChE, and anti-Parkinson's disease activities. In our previous study, seventeen abietane diterpenoids were isolated from this species, and their neuroprotective and cytotoxic activities were discussed.…”