The structures of garcinones a, b and c: Three new xanthones from Garcinia mangostana

Cytotoxic Prenylated Xanthones from the Young Fruit of Garcinia mangostana

“…Compounds 4-19 were identified as thwaitesixanthone (4), 12) demethylcalabaxanthone (5), 11) garcinone B (6), 10) compound 7, 11) b-mangostin (8), 10) 8-desoxygartanin (9), 13) gartanin (10), 14) garcinone E (11), 15) the major metabolite amangostin (12), 10) mangostinone (13), 10) the second major metabolite g-mangostin (14), 11) mangostanol (15), 10) mangostanin (16), 11) garcinone D (17), 11) garcinone C (18), 16) and the third major metabolite 11-hydroxy-1-isomangostin (19) Table 2. Based on these observations, the following conclusions can be drawn regarding these isolates: 1) For high activity, the xanthones should contain tetraoxygen functions with two C 5 units in rings A and C (as in 8, 11, 12, 14).…”

“…Mangostanol (15) (9 mg), 10) mangostenone C (1) (4 mg), mangostenone D (2) (6 mg), and mangostanin (16) (6 mg), 11) were isolated from repeated individual column chromatography (silica gel) of fractions 7g (561 mg, using a hexane-EtOAc gradient system as eluent), 7h (203 mg, eluted with CHCl 3 -MeOH, 99 : 1 to 5 : 95), and 7i (204 mg, eluted with CH 2 Cl 2 -MeOH, 99.5 : 0.5 to 90 : 10), respectively. Similar fractionation of fraction 8 (3.75 g), eluted with a gradient of CH 2 Cl 2 and CH 2 Cl 2 -MeOH (70 : 30), yielded 11 fractions, in which garcinone D (17) (90 mg) 11) and garcinone C (18) (20 mg) 16) were obtained from subsequent column chromatography (silica gel, eluted with a gradient of CH 2 Cl 2 and CH 2 Cl 2 -MeOH) of fraction 8h (2.29 g). Similarly, purification of fraction 9 (4.20 g) using column chromatography (silica gel, CH 2 Cl 2 -MeOH 99 : 1 to 30 : 70 in 3% increments of the polar solvent) gave five fractions, mangostenone E (3) (9 mg) and the third major isolate, 11-hydroxy-1-isomangostin (19) (235 mg), 17) were isolated from two successive column chromatographies (silica gel, CH 2 Cl 2 -MeOH 97 : 3 to 95 : 5) of fractions 9b (852 mg) and 9d (1.94 g), respectively.…”

“…In our previous study, the isolation of 17 xanthones including three new xanthones, mangostenol and mangostenones A and B, from the green fruit (14-week maturity stage) of this plant and their antituberculosis activity were already described. 10,11) In a continuation of this work, the EtOAc-soluble extract obtained from the young fruit (7-week maturity stage) of G. mangostana was subjected to a chemical investigation leading to the isolation and structural elucidation of three new prenylated xanthones, mangostenones C (1), D (2), and E (3), in addition to 16 previously reported xanthones, thwaitesixanthone (4), 12) demethylcalabaxanthone (5), 11) garcinone B (6), 10) compound 7, 11) b-mangostin (8), 10) 8-desoxygartanin (9), 13) gartanin (10), 14) garcinone E (11), 15) the major metabolite a-mangostin (12), 10) mangostinone (13), 10) the second major metabolite g-mangostin (14), 11) mangostanol (15), 10) mangostanin (16), 11) garcinone D (17), 11) garcinone C (18), 16) and the third major metabolite 11-hydroxy-1-isomangostin (19). 17) We here report on the structural elucidation of the three new compounds and the in vitro cytotoxic activities of xanthones 1-19 against three human cancer cell lines, epidermoid carcinoma of the mouth (KB), breast cancer (BC-1), and small cell lung cancer (NCI-H187).…”

Xanthone and Benzophenone Glycosides from the Stems of Cratoxylum formosum ssp. pruniflorum

“…Other known compounds were identified as cochinchinone G (5), 15) 5-O-methyl-2-deprenylrheediaxanthone B (6), 16) isocudraniaxanthone A (7), 17) isocudraniaxanthone B (8), 17) garcinone B (9), 18) xanthone V 1 (10), 19) by comparison of their physical and spectroscopic data with those reported previously.…”

Chromene and Prenylated Xanthones from the Roots of Cratoxylum formosum ssp. pruniflorum

“…pruniflorum was subjected to chemical investigation leading to the isolation of two new xanthones, pruniflorone K (1) and L (2), together with thirteen known xanthones identified as cochinchinone A (3), 11) formoxanthone B (4), 8) 1,7-dihydroxy-8-methoxyxanthone (5), 12) cochinchinone I (6), 10) 1,3,7-trihydroxy-2,4-diisoprenylxanthone (7), 13) celebixanthone methyl ether (8), 14) vieillardiixanthone B (9), 15) macluraxanthone (10), 16) dulcisxanthone B (11), 17) norcowanin (12), 18) 5,9-dihydroxy-8-methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2H,6H-pyrano [3,2b]xanthone (13), 19) Garcinone B (14), 20) and brasilixanthone (15). 21) Their structures were elucidated by NMR analysis and comparison of their spectroscopic data with those reported in the literatures.…”