Three new kavalactone dimers from Piper methysticum (kava)

Abstract

Three new dimeric kavalactones, designated as diyangonins A-C (1-3), along with two known analogs were isolated from the roots of Piper methysticum. Their structures were elucidated by means of extensive analysis of their 1D, 2D NMR, and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units in head-to-tail or head-to-head mode. Compounds 1-5 were evaluated for their cytotoxic activities against human tumor cell lines.

3D Imaging and metabolomic profiling reveal higher neuroactive kavalactone contents in lateral roots and crown root peels of Piper methysticum (kava)

“…Of all the kavalactones for which we built statistical models, kavain, desmethoxyyangonin, and dihydromethysticin are especially of interest due to their well-known neurological activities amongst other kavalactones in the plant [ 10 , 11 , 23 ]. Consistent with the traditional use of roots in folk medicine, concentrations of all 3 of these metabolites were significantly lower in both stem tissue types than all of the root samples based on FDR-adjusted Student t -tests for all 29 tested metabolites (Fig.…”

“…Pathways of enzymes that affect the biosynthesis of these compounds have been identified and reported by Yang et al [ 10 ]. Novel dimeric kavalactones, namely, diyangonins (A–C), have also been reported to be isolated from kava roots [ 10 , 11 ]. The kavalactone profiles genetically vary among varieties.…”

Biological Activity, Hepatotoxicity, and Structure-Activity Relationship of Kavalactones and Flavokavins, the Two Main Bioactive Components in Kava (Piper methysticum)

“…A series of kavalactone dimers were also isolated and identified via extensive phytochemical investigation on the roots of kava [17][18][19]. By using classical chromatographic separation methods combined with spectrum identification techniques, a series of novel dimeric kavalactones, namely, diyangonins A (20), diyangonins B (21), diyangonins C (22), yangonindimers A (23), yangonindimers B (24), yangonindimers C (25), kavalactone A (26), aniba-dimer A (27), rel-, trans-3-bis[6-(4-methoxy-2-pyronyl)]-cis-2, trans -4diphenyl cyclobutane (28), and 6,6′-(3,4-diphenylcyclobutane-1,2-diyl) bis (4-methoxy-2H-pyran-2-one) (29), were isolated and elucidated from kava [17][18][19]. e chemical structures of compounds 20-29 are listed in Figure 1.…”

Plant-Derived Kavalactones and Their Bioactivities

“…[23] Kavalactone dimers Diyangonins A-C (38, 39, 41), yangonindimers A-C (43-45), and three known anologues [(rel-trans-3-bis[6-(4-methoxy-2-pyronyl)]-cis-2,trans-4-diphenyl cyclobutane (40) 6,6′-(3,4-diphenylcyclobutane-1,2-diyl)bis(4-methoxy-2H-pyran-2-one) (42), aniba-dimer A (46)], were isolated from roots of P. methysticum. [24,25] Kavalactone dimers (r-8,c-7´,t-7-8,8´-11,12dimethoxyphenyl-7,7´-di-[6-(4-methoxy-2-pyronyl)]-cyclobutane, 47) and (rel-(6R,7S,8S,5´S)-4´-methoxy-8-(11,12-dimethoxyphenyl)-7-[6-(4-methoxy-2-pyronyl)]-6-(E)-styryl-1´-oxabicyclo[4 ,2,0] octa-4´-en-2´-one, 48) were isolated from the trunk wood of Aniba species. [26] Hybrids of kavalactone and other types Three hybrids, katsumadain A (49), katsumadain B (50), and katsumadain (51), which were fused by kavalactone and diarylheptanoid or terpene, have been isolated from the seeds of Alpinia katsumadai.…”