New Rare Sinapoyl Acylated Flavonoid Glycosides Obtained from the Seeds of Lepidium apetalum Willd

Abstract

Seven new rare sinapoyl acylated flavonoid glycosides, apetalumosides A1 (1), B8 (2), B9 (3), B10 (4), B11 (5), B12 (6), and C1 (7) were isolated from the seeds of Lepidium apetalum Willd. Their structures were elucidated by chemical and spectroscopic methods.

Bioactive Constituents Obtained from the Seeds of Lepidium apetalum Willd

“…The 50% EtOH extract of L. apetalum seeds was treated with the same experimental process as reported in reference [ 1 , 2 ] to obtain 95% EtOH eluate, which was separated by silica gel, octadecylsilica (ODS), Sephadex LH-20 CC, and finally preparative HPLC to yield compounds 1 – 25 . Their structures are shown in Figure 1 and Figure 2 .…”

“…In the HSQC–TOCSY spectrum, correlations between the following proton and carbon pairs were observed: δ C 100.6 (C-1′′) and δ H 3.08 (H-4′′), 3.21 (H-2′′), 3.26 (H-3′′), 5.50 (H-1′′); δ H 3.08 (H-4′′) and δ C 60.8 (C-6′′), 69.8 (C-4′′), 74.2 (C-2′′), 76.3 (C-5′′), 76.8 (C-3′′); δ H 5.12 (H-1′′′) and δ C 69.2 (C-4′′′), 73.0 (C-2′′′), 76.2 (C-3′′′), 99.7 (C-1′′′); δ H 3.71, 3.99 (H 2 -6′′′) and δ C 68.9 (C-6′′′), 69.2 (C-4′′′), 73.0 (C-2′′′), 75.3 (C-5′′′), 76.2 (C-3′′′); δ C 103.5 (C-1′′′′) and δ H 3.22 (H-2′′′′), 3.34 (H-4′′′′), 4.35 (H-1′′′′), 4.90 (H-3′′′′); δ H 4.90 (H-3′′′′) and δ C 60.7 (C-6′′′′), 68.1 (C-4′′′′), 77.4 (C-5′′′′), 103.5 (C-1′′′′). Acid hydrolysis of 1 yielded d -glucose, which was identified by retention time and optical rotation using chiral detection by HPLC analysis [ 1 , 2 ].…”

“…The seeds of L. apetalum (10 kg) were treated with the same experimental process as reported in reference [ 1 , 2 ], as a result, the 95% EtOH (Fraction 1) and H 2 O (Fraction 2) eluates were obtained.…”

“…In our on-going program of screening the phytochemical and bioactive constituents from Lepidium apetalum seed extract [ 1 , 2 ], three new compounds, apetalumosides C 1 ( 1 ), D ( 2 ), and 1-thio-β- d -glucopyranosyl(1→1)-1-thio-α- d -glucopyranoside ( 3 ), along with twenty-two known isolates, astragalin ( 4 ) [ 3 ]; kaempferol 3- O -β- d -glucopyranosyl-7- O -β- d -gentiobioside ( 5 ) [ 4 ]; drabanemoroside ( 6 ) [ 5 ]; quercetin 3- O -β- d -glucopyranosyl-7- O -β- d -gentiobioside ( 7 ) [ 4 ]; quercetin 3- O -α- l -rhamnopyranosyl(1→2)-α- l -arabinopyranoside ( 8 ) [ 6 ]; isorhamnetin 3- O -β- d -glucopyranoside ( 9 ) [ 7 ]; isorhamnetin 3,4′- O -β- d -diglucoside ( 10 ) [ 8 ]; isorhamnetin 3- O -β- d -glucopyranosyl-7- O -β- d -gentiobioside ( 11 ) [ 4 ]; 2- O -(3,4-dihydroxybenzoyl)-2,4,6-trihydroxyphenylacetic acid 4- O -β- d -glucopyranoside ( 12 ) [ 9 ]; 4,9-di- O -β- d -glucosyl sinapoyl alcohol ( 13 ) [ 10 ]; 3′,5′-dimethoxy-4- O -β- d -glucopyranosyl cinnamic acid ( 14 ) [ 11 ]; sinapoylglucose ( 15 ) [ 12 ]; sinapoyl-9-sucrosecoside ( 16 ); 1( E ),2( E )-di- O -sinapoyl-β- d -glucopyranoside ( 17 ) [ 13 ]; 1,2-disinapoylgentiobiose ( 18 ) [ 14 ]; lariciresinol 4′- O -β- d -glucopyranoside ( 19 ) [ 15 , 16 ]; (7 S ,8 R )-aegineoside ( 20 ) [ 17 , 18 ]; l -tryptophan ( 21 ) [ 19 ]; thymidine ( 22 ) [ 20 ]; adenosine ( 23 ) [ 21 ]; stachyose ( 24 ) [ 22 ]; and TgSSTg ( 25 ) [ 23 ] were obtained. Among the known isolates, 5 – 8 , 10 – 13 , 16 – 20 , and 25 were obtained...…”

New Acylated Flavonol Glycosides and a Phenolic Profile of Pritzelago alpina, a Forgotten Edible Alpine Plant

“…nipposinica) [ 13]. Sinapoyl glycosides of kaempferol and quercetina re less frequent in nature,a nd have been reported from Brassicaceaespecies such as Brassica napus [14], Lepidium sativum [15], and L. apetalum [16]. To the best of our knowledge,t his is the first report of flavonoid glycosidesa cylatedw ith 2-methylbutanoic or isobutyric acid moieties in aplant of the family of Brassicaceae.Such compounds have been previously reported from other botanical families such as Astereaceae [17], Ranunculaceae [18], and Convolvulaceae [19].…”