title: Anticancer and antioxidant tannins from Pimenta dioica leaves.
abstract: Two galloylglucosides, 6-hydroxy-eugenol 4-O-(6'-O-galloyl)-beta-D-4C1-glucopyranoside (4) and 3-(4-hydroxy-3-methoxyphenyl)-propane-1,2-diol-2-O-(2',6'-di-O-galloyl)-beta-D -4C1-glucopyranoside (7), and two C-glycosidic tannins, vascalaginone (10) and grandininol (14), together with fourteen known metabolites, gallic acid (1), methyl gallate (2), nilocitin (3), 1-O-galloyl-4,6-(S)-hexahydroxydiphenoyl-(alpha/beta)-D-glucopyranose (5), 4,6-(S)-hexahydroxydiphenoyl-(alpha/beta)-D-glucopyranose (6), 3,4,6-valoneoyl-(alpha/beta)-D-glucopyranose (8), pedunculagin (9), casuariin (11), castalagin (12), vascalagin (13), casuarinin (15), grandinin (16), methyl-flavogallonate (17) and ellagic acid (18), were identified from the leaves of Pimenta dioica (Merr.) L. (Myrtaceae) on the basis of their chemical and physicochemical analysis (UV, HRESI-MS, 1D and 2D NMR). It was found that 9 is the most cytotoxic compound against solid tumour cancer cells, the most potent scavenger against the artificial radical DPPH and physiological radicals including ROO*, OH*, and O2-*, and strongly inhibited the NO generation and induced the proliferation of T-lymphocytes and macrophages. On the other hand, 3 was the strongest NO inhibitor and 16 the highest stimulator for the proliferation of T-lymphocytes, while 10 was the most active inducer of macrophage proliferation.
authors.affiliation: Natural Products Group, Nobel Project Laboratory, National Research Centre, El-Behoos St., Dokki, Cairo, Egypt.
authors.forename: Mohamed S A
authors.initials: MS
authors.lastname: Marzouk
authors.forename: Fatma A
authors.initials: FA
authors.lastname: Moharram
authors.forename: Mona A
authors.initials: MA
authors.lastname: Mohamed
authors.forename: Amira M
authors.initials: AM
authors.lastname: Gamal-Eldeen
authors.forename: Elsayed A
authors.initials: EA
authors.lastname: Aboutabl
mesh_terms: D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000494:pharmacology; D000975:Antioxidants / Q000302:isolation & purification* / Q000494:pharmacology; D001943:Breast Neoplasms; D006528:Carcinoma, Hepatocellular; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects*; D005260:Female; D006801:Humans; D017665:Hydroxyl Radical; D008113:Liver Neoplasms; D009682:Magnetic Resonance Spectroscopy; D027841:Pimenta; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves; D011720:Pyrazoles / Q000737:chemistry; D011743:Pyrimidines / Q000737:chemistry; D013634:Tannins / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; C493309:N(4)-benzyl-N(6),N(6)-dimethyl-1-1(tert-butyl)-1H-pyrazolo(3,4-d)pyrimidine-6,4-diamine; D010936:Plant Extracts; D011720:Pyrazoles; D011743:Pyrimidines; D013634:Tannins; D017665:Hydroxyl Radical