4
J.-S. JIANG ET AL.
and a 5,7-dihydroxy-1(3H)-isobenzofuranone moiety. Furthermore, the HMBC corre-
lations between H-100/C-5, and H-200/C-70 confirmed that the glucosyl moiety and the
galloyl group were located at C-5 of the isobenzofuranone, and C-200 of the glucosyl,
respectively. Thus, compound 1 was defined and named polyphthaliside A.
Compound 2 was also isolated as a white powder. Its molecular formula of
C21H20O13 was determined by HR-ESI-MS. The IR spectrum showed the presence of
1
hydroxyl, carbonyl and aromatic groups. The H NMR spectral data (Table 1) showed
aromatic proton signals at dH 6.96 (2H, s, H-20,60), 6.50 (1H, s, H-4), and 6.42 (1H, s,
H-6), an anomeric proton signal at dH 4.95 (1H, d, J ¼ 8.5 Hz, H-100), and two methy-
lene proton signals at dH 5.05 (1H, d, J ¼ 16.0 Hz, H-3a) and 4.92 (1H, d, J ¼ 16.0 Hz,
H-3b). The 13C NMR spectrum of 2 showed 21 carbon signals (Table 1) comprising
seven carbons of a galloyl group, six carbons of a glycosyl moiety, and eight carbons
of 5,7-dihydroxy-1(3H)-isobenzofuranone coupling with 2D NMR spectra. These
observations suggested that compound 2 was still an isobenzofuranone derivative.
The 13C NMR spectrum of 2 was similar to the corresponding signals of compound 1
except of chemical shift of C-600 in the glucosyl group. This indicated that the galloyl
group was linked to the C-600 position based on the information that the chemical
shift was moved from dC 60.3 (C-600) in compound 1 to dC 63.5 (C-600) in compound
2. Additionally, b-D-pyranoglucose was confirmed by the acid hydrolysis and located
at C-5 by the correlation of H-100/C-5 in HMBC experiment (Figure 2). Finally, com-
pound 2 was characterized as depicted and named polyphthaliside B.
Compound 3 was obtained as a white powder. The IR spectrum of 3 showed the
presence of hydroxyl groups (3305 cmꢀ1), carbonyl groups (1667 cmꢀ1), benzene ring
(1509, 1465 cmꢀ1) and methyl (2932, 1347 cmꢀ1). 3 possessed a molecular formula of
1
C22H22O11 on the basis of HR-ESI-MS at m/z 463.1233 [M þ H]þ. The H NMR
spectrum (Table 1) showed three phenolic hydroxyl protons at dH 11.06 (1H, s, OH-
8) and 9.57 (2H, s, OH-20,40), two sets of meta-coupled aromatic protons at dH 6.75
(1H, d, J ¼ 2.0 Hz, H-5) and 6.63 (1H, d, J ¼ 2.0 Hz, H-7), and dH 6.25 (1H, d,
J ¼ 1.5 Hz, H-30) and 6.19 (1H, d, J ¼ 1.5 Hz, H-50), an olefin bond proton at dH 6.66
(1H, s, H-4), an anomeric proton at dH 5.04 (d, J ¼ 7.0 Hz, H-100), and a methyl pro-
ton at dH 2.13 (3H, s). Coupling with 2D NMR, the 13C NMR spectrum (Table 1)
displayed a set of saccharide carbon signals at dC 100.4 (C-100), 73.6 (C-200), 77.7
(C-300), 70.0 (C-400), 77.0 (C-500) and 61.0 (C-600). The saccharide moiety was assigned
to be b-form by the large coupling constant of the anomeric proton signal and the
13C NMR data. Furthermore, cellulose hydrolysis of 3 yielded D-glucose based on the
GC analysis, which suggested that there was a b-D-glucopyrancose in compound 3.
13
The C NMR and 2D NMR data of 3 further established a methyl at dC 20.3 (C-70),
and a tetrasubstituted phenyl at dC 111.8 (C-10), 157.6 (C-20), 100.7 (C-30), 159.7
(C-40), 108.8 (C-50) and 139.6 (C-60). In addition, the tetrasubstituted phenyl was con-
cluded to be 20,40-dihydroxy-60-methylphenyl coupling with the correlations of OH-20
(dH 9.57)/C-20, OH-40 (dH 9.57)/C-40, and H-CH3/C-10, C-50, C-60 in the HMBC
experiment (Figure 2). Except for 13 carbons of a glucosyl and 20,40-dihydroxy-60-
methylphenyl, the residual 9 carbon signals of 3 showed close similarities to those of
6,8-dihydroxy-3-(2-hydroxypropyl)-isocoumarin [7], which confirmed that compound
3 has a 3,6,8-trisubstituted isocoumarin group. Meanwhile, the HMBC correlations of