Chemical constituents from Lycopodiella cernua and their anti-inflammatory and cytotoxic activities

Piperlongosides A–C, Three New Phenolic Constituents From Piper longum L.

“…These data were similar to those of lycocernuaside E, suggesting they have the same planar structure. 15 This was confirmed by the HSQC, HMBC, and COSY spectra as shown in Figure 2. The HMBC correlations from H-1′ ( δ H 4.81) to C-1 ( δ C 147.5) and H-8 ( δ H 3.43) to C-1′′ ( δ C 154.1) indicated a glucose unit linked to C-1 and carbon C-1′′ linked to C-8.…”

“…as evidenced by HMBC correlations from methoxy protons at δ H 3.84 and 3.83 to C-2 (δ C 150.4) and C-2 ′′ (δ C 151.1), respectively. The carbon chemical shifts of C-7 (δ C 73.8), C-8 (δ C 84.9), and C-9 (δ C 62.4) of 2 differed from those of the erythro configuration in lycocernuaside E [δ C 73.5 (C-7), 85.4 (C-8), and 62.0 (C-9)] measured in the same solvent, CD 3 OD 15. Furthermore, in the HSQC spectra, the H 2 -9 protons appeared separately at δ H 3.60 and 3.87 in lycocernuaside E, while they appeared as a doublet at δ 3.89 (2H, d, 7.2 Hz) in 2.…”