Mahmoud A. Ramadan

Acetophenones, a chalcone, a chromone and flavonoids from Pancratium maritimum

Abstract The ethanolic extract of fresh flowering bulbs of Pancratium maritimum L. yielded a new chromone, maritimin, two new polyoxygenated acetophenones, together with the flavonoids syzalterin, (−)-farrerol and (−)-liquiritigenin, and the chalcone isoliquiritigenin. The structures of the isolated compounds were determined through spectral analyses including NMR and MS studies.

Two non-hydroxylated alkaloids in Crinum augustum☆

Abstract Several alkaloids were isolated from Crinum augustum grown in Assiut, Egypt. Two were identified as lycorine and buphanisine. In addition two new non-hydroxylated alkaloids of identical molecular formula C 17 H 19 NO 4 were investigated by spectroscopic methods. The gross structure of the first, termed augustine, belongs to the 1,2-epoxy-5, 10-b-ethanophenanthridine-type. In contrast the second could not be related to any of the known alkaloid types of the Amaryllidaceae.

Chemical constituents from Chorisia chodatii flowers and their biological activities

From the flowers of Chorisia chodatii Hassl. (family: Bombacaceae), seventeen compounds were isolated and identified, including: two sterols, β-sitosterol (1) and β-sitosterol 3-O-β-D-glucopyranoside (10); two furanoids, 5-hydroxymethyl furfural (3) and (3R,4R,5S)-3,4-dihydroxy-5-methyl-dihydrofuran-2-one (12); two coumarins, scopoletin (8) and aesculetin (9); four phenolic acids and esters, ethyl vanillate (4), vanillic acid (5), protocatechuic acid ethyl ester (6) and p-hydroxy benzoic acid (7); five flavonoids, kaempferol 3-O-β-D-(6″-acetyl)-glucopyranoside (13), kaempferol 3-O-β-D-(6″-E-p-coumaroyl)-glucopyranoside (14), kaempferol 3-O-β-D-glucopyranoside (15), luteolin 7-O-β-D-glucopyranoside (16) and apigenin 7-O-neohesperidoside (17), in addition to mono-octyl phthalate (2) and succinic acid (11). All the isolated metabolites were reported for the first time from this plant, and among them, compounds (3), (4), (6), (7), (12) and (13) were isolated for the first time from family Bombacaceae. Besides, this is the first report for isolation of (2) in a pure form from a natural source. These phytochemical data revealed important chemotaxonomic value and may broaden the use of this plant in future phytotherapy. Moreover, all of the obtained phytocompounds were evaluated for their DPPH free radical scavenging properties and cytotoxic activities against the human lung cancer cell line A549.