Phenolic Compounds from Selaginella moellendorfii

Abstract

Chemical investigation of the leaves and roots of Selaginella moellendorfii Hieron has resulted in the isolation and characterization of two new flavone glucosides, 7-O-(β-glucopyranosyl(1→2)-[β-glucopyranosyl(1→6)]-β-glucopyranosyl)flavone-3',4',5,7-tetraol (1) and 7-O-(β-glucopyranosyl(1→2)-[β-glucopyranosyl(1→6)]-β-glucopyranosyl)flavone-4',5,7-triol (2), two new biflavonoids, 2,3-dihydroflavone-5,7,4'-triol-(3'→8″)-flavone-5″,6″,7″,4'''-tetraol (3) and 6-methylflavone-5,7,4'-triol-(3'→O→4''')-6″-methylflavone-5″,7″-diol (4), two new lignans, (7'E)-3,5,3',5'-tetramethoxy-8 : 4'-oxyneolign-7'-ene-4,9,9'-triol (5) and 3,3'-dimethoxylign-8'-ene-4,4',9-triol (6), together with two known monolignans, four known lignans, and four known biflavonoids. Their structures were established by spectroscopic means and by comparison with literature values.

Chemodiversity in Selaginella: a reference system for parallel and convergent metabolic evolution in terrestrial plants

“…Medicinally, biflavonoids associate with assorted pharmacological properties including antimicrobial, antiviral, anticancer, anti-inflammatory, and anti-fibrillogenesis activities (Ma et al, 2001; Tang et al, 2003; Pan et al, 2005; Setyawan, 2011; Thapa et al, 2011). Seven dimeric linkage types are found in biflavonoids isolated from Selaginella , including 2′–8″ ( 14 ), 3–3‴ ( 15 ), 3′–6″ ( 16 – 21 ), 3′–8″ ( 22 – 36 ), 3- O -4‴ ( 37 ), 3′- O -4‴ ( 38 ), and 4′- O -6″ ( 39 – 47 ; Lin et al, 1994, 2000; Silva et al, 1995; Lee et al, 1996, 2008, 2009; Sun et al, 1997; Ma et al, 2001, 2003; Kang et al, 2004; Cheng et al, 2008; Feng et al, 2008; Zheng et al, 2008, 2011; Zhu et al, 2008; Cao et al, 2009, 2012; Liu et al, 2010; Setyawan, 2011; Wu and Wang, 2011; Yang et al, 2011; Zhang et al, 2011, 2012a; Figure 3D ). Although little is known about the mechanisms governing biflavonoid crosslinks in plants, biflavonoids likely dimerize via radical coupling reactions mediated by peroxidases (Yamaguchi and Kato, 2012), a catalytic reaction shared with lignan and lignin biosynthesis (Umezawa, 2003; Ralph et al, 2004).…”

“…The core chemical scaffold of lignans are dimeric phenylpropanoid units, including allylphenols and hydroxycinnamyl alcohols and acids, generated through oxidative coupling of radical subunits produced by the actions of laccases or peroxidases (Umezawa, 2003). A number of lignans with shared β-β′/γ- O -α′/α- O -γ′ ( 48 – 50 ), β-β′/γ- O -γ′ ( 51 – 55 ), and β-β′/α- O -γ′ ( 56 – 57 ) linkages were identified in Selaginella species (Lin et al, 1994; Pan et al, 2001; Feng et al, 2009; Wu and Wang, 2011; Figures 4A–C ). Notably, compounds 48 – 50 result from dimeric sinapoyl alcohol units, consistent with the finding that Selaginella deposits sinapoyl alcohol-derived polymeric syringyl (S) lignin, a lignin type mistakenly thought to be restricted to flowering plants (Towers and Gibbs, 1953; Weng et al, 2008).…”

Metabolomic Profiling in Selaginella lepidophylla at Various Hydration States Provides New Insights into the Mechanistic Basis of Desiccation Tolerance

“…Various Selaginella species have been recognized for their potential therapeutic value as anitviral, antimicrobial, or anticancer bioactivities. For example, several novel flavones and biflavones have been characterized from S. lepidophylla (Aguilar et al, 2008), S. chrysocaulos and S. bryopteris (Swamy et al, 2006), S. labordei (Tan et al, 2009), S. moellendorffii (Cao et al, 2010;Liu et al, 2010;Wang et al, 2011;Wu and Wang, 2011), S. uncinata (Zheng et al, 2011a), and S. tamariscina (Zhang et al, 2011). Antimicrobial alkaloids have also been characterized from S. moellendorfii (Wang et al, 2009).…”

Phenolic Constituents from Platycodon grandiflorum Root and Their Anti-Inflammatory Activity

“…A series of twenty-one compounds, including six lignols (1)(2)(3)(4)(5)(6), four phenolic compounds (7-10), a neolignan (11), three alkyl aryl ether-type lignans (12)(13)(14), two furofurantype lignans (15)(16), three benzofuran-type lignans (17)(18)(19), a tetrahydrofuran-type lignans (20), and a dibenzylbutane-type lignan (21), were isolated from the ethyl acetate-soluble fraction of the methanol extract of the root of P. grandiflorum. Their structures were identified as (+)-(7R,8R)-palmitoyl alatusol D (1), (+)-(7R,8R)-linoleyl alatusol D (2), (+)-(7R,8R)lignoceryl alatusol D (3) [16], (+)-(7R,8R)-alatusol D (4) [17], (−)-(7S,8R)-alatusol D (5) [18], (+)-(7S,8R)-guaiacylglycerol ( 6) [19], 3,3 -dimethoxy [1,1 -biphenyl]-4,4 -diol ( 7) [20], (+)-4hydroxy-3-methoxyphenylglycol (8) [21], vanillin (9), vanillic acid (10 [23], wikstroemol (13) [24], threo-4,7,9,9 -tetrahydroxy-3,3 -dimethoxy-8-O-4 -neolignan ( 14) [25], (+)-lariciresinol ( 15) [26], 3 -demethyl-(+)-lariciresinol ( 16) [27], (−)-dehydrodiconiferyl alcohol (17) [28], hawthornnin G (18) [29], dihydrodehydrodiconiferyl alcohol (19) [30], (+)-neoolivil (20) [31], and (−)-secoisolariciresinol (21) [32], based on the consistency of their analytical data with those from ...…”