Flavonoids from the Aerial Parts of Diplomorpha canescens

6,8-Di-C-methyl-flavonoids with neuroprotective activities from Rhododendron fortunei

“…The 1 H NMR spectrum of 1 (Table 1) (Table 2) and DEPT spectra displayed resonances for a ketone carbonyl, eight substituted aromatic carbons, four aromatic methines, a glucopyranose unit (δ C 105.5, C-1′′; 78.3, C-5′′; 78.0, C-3′′; 75.9, C-2′′; 71.6, C-4′′; 62.8, C-6′′), two oxymethines, and two methyls. The above NMR data suggested that compound 1 is a glycosylated derivatives of the known compound 7 21 . The HSQC, 1 H-1 H COSY, and HMBC data were used to establish the planar structure of compound 1 (Figure 2).…”

“…The β-linkage for two sugar units was deduced from the large coupling constants of the anomeric protons (J = 6.8 Hz for glucose and J = 7.4 Hz for xylose). The trans-relationship of H-2 and H-3 in 2 was determined by the large coupling constant J = 11.8 Hz, and the 2R,3R absolute configuration was suggested by the strong positive Cotton effect at 353 nm in the CD spectrum 21,28 , which is almost the same as that of 1. Thus, compound 2 was designated as (2R,3R)-6,8-di-C-methyl-5,7,4′-trihydroxyflavano-nol 7-O-β-D-xylopyranosyl(1→6)-β-Dglucopyranoside.…”

Phenolic Compounds from the Aerial Parts of <i>Diplomorpha canescens</i>

“…2) We have previously reported two new and eleven known flavonoids from the aerial parts of D. canescens. 3) In continuing further chemical analysis, we isolated and identified a new C-methyl flavanone glucoside and fourteen known phenolic compounds from aerial parts of D. canescens, which are reported in this paper.…”

Diplomorphanins A and B: New <i>C</i>-Methyl Flavonoids from <i>Diplomorpha canescens</i>

“…2) We have previously reported four new compounds such as (2R,3S)-6,8-di-C-methyldihydrokaempferol, (2R,3R)-6,8-di-C-methyldihydrokaempferol, 3) farrerol 4′-O-β-d-glucopyranoside (4), 4) and diplomorphanone A 5) along with twenty-five known compounds from the aerial parts of D. canescens. In continuing further chemical analysis, we isolated and identified two new C-methyl flavonoids, diplomorphanins A (1) and B (2) along with farrerol 7-O-β-dglucopyranoside (3) 6) ( Fig. 1) which are reported in this paper.…”