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Subfraction D1 was applied to an ODS column and eluted by a gradient MeOH-H SB 2 sb O (30:70-80:20) to provide compound B 4 b (28.0 mg). Subfraction C2 was further separated by silica gel CC with petroleum ether-ethyl acetate (20:80-50:50) to afford compound B 10 b (13.0 mg). Fraction B was purified by silica gel CC with petroleum ether-ethyl acetate (100:0-80:20) to yield compounds B 2 b (15.0 mg), B 6 b (2.6 mg), and B 9 b (551.0 mg). Subfraction C1 was purified on an ODS column using a stepped gradient of MeOH-H SB 2 sb O (40:60-80:20), Sephadex LH-20 gel column (CH SB 2 sb Cl SB 2 sb -MeOH, 50:50), and silica gel CC with petroleum ether-ethyl acetate (10:90-50:50) to give compounds B 5 b (4.2 mg) and B 7 b (6.3 mg). [Extracted from the article]

Based on the above data, it was speculated that compound B 1 b was monoacetylasterric acid [[7]], and the structure of B 1 b was further confirmed by single crystal X-ray diffraction analysis (Fig. They were identified as monoacetylasterric acid ( B 1 b ) [[7]], methyl asterrate ( B 2 b ) [[8]], asterric acid ( B 3 b ) [[8]], methyl dichloroasterrate ( B 4 b ) [[9]], penicillither ( B 5 b ) [[10]], geomycin A ( B 6 b ) [[11]], sulochrin ( B 7 b ) [[12]], 1-methyl emodin ( B 8 b ) [[13]], and isorhodoptilometrin ( B 9 b ) [[14]]. The SP 13 sp C NMR and HSQC spectra showed 19 carbon signals, including three carbonyl carbons ( 165.2, 165.3, and 168.7), 12 aromatic carbon signals ( 104.7-156.6), two methoxy carbon signals ( 52.1 and 56.0), and two methyl carbon signals ( 20.6 and 21.0). Its SP 1 sp H and SP 13 sp C NMR data are similar to the known compound B 2 b , indicating that B 1 b is also a diphenyl ether. [Extracted from the article]