Records of Natural Products Articles

A new triterpene glycoside (1), isacoside, together with seven known glycosides and a common aglycone were isolated from Cephalaria isaurica and Cephalaria stellipilis. Two glycosides of the known compounds (vaniloloside and picein) were detected in this genus for the first time. The structures of all compounds were determined by spectroscopic analysis including 1D and 2D NMR, HRESIMS techniques and chemical evidence.

In search for antiproliferative compound against human cancer cells (A549, SK-OV-3, SK-MEL-2, XF498, HCT15), a chloroform soluble extract obtained by re-extraction of the methanol extract of whole plant of Carpesium rosulatum MlQ. (Compositae) exhibited cytotoxic activity. Four germacrane sesquiterpene lactones 2α,5-epoxy-5,10-dihydroxy-6-angeloyl-oxy-9β-isobutyloxy-germacran-8α,12-olide, 2α,5-epoxy-5,10-dihydroxy-6α,9β-diangeloyloxy-germacran-8α,12-olide, 2α,5-epoxy-5,10-dihydroxy-6α-angeloyloxy-9β-(3-methyl-butanoyloxy)-germacran-8α,12-olide, and 2β,5-epoxy-5,10-dihydroxy-6α,9β-diangeloyloxy-germacran-8α,12-olide were isolated from the chloroform extract of C . rosulatum, and 2α,5-epoxy-5,10-dihydroxy-6α,9β-diangeloyloxy-germacran-8α,12-olide showed the most potent cytotoxicity with IC 50 value of 6.01 μM against SK-MEL-2 .

The chemical composition of hydrodistilled oils obtained from the leaves of six Citrus reticulata Blanco (mandarin) cultivars grown in Nigeria were examined by GC and GC/MS, the result of their chemical composition were further submitted to cluster analysis. Fifty seven constituents were characterized accounting for 88.2 - 96.7% of the total oils. Sabinene, g -terpinene, P-cymene, d -3-carene and (E)- b -ocimene were observed in great variability in all the oils. Other constituents include linalool, myrcene, terpinen-4-ol and cis-sabinenehydrate. In addition, limonene, terpinolene, b -pinene, and a -pinene were also detected in appreciable concentrations. b -sinensal and a -sinensal were isolated by preparative GC and characterized by one- and two-dimensional NMR techniques.

The essential oils obtained from leaves and roots of Aralia cachemirica were analyzed by capillary GC and GC-MS . A total of 25 constituents, representing 9.14 % in leaf essential oil and 26 components, representing 96.5% in root essential oil were identified. Both leaf and root oils were characterized by the presence of α-pinene (41.0%, 52.7%) and β-pinene (35.1%, 13.6%) as the major constituents. Other constituents identified in significant amount were b -caryophyllene, terpinen-4-ol, myrtenol and borneol.

Aerial parts of Echinophora tenuifolia subsp. sibthorpiana were subjected to hydrodistillation and the oil obtained was analyzed by GC and GC-MS. The essential oil was dominated by the presence of monoterpenes with α -phellandrene (43.8%) being the major component, followed by the high percentage of the phenylpropanoic derivative methyleugenol (28.6%), while sesquiterpenes were not detected.

From the shade-dried and powdered roots of S. undulata ssp. deliciosa eight known compounds; β-Amyrin acetate, methyl Oleanate, methyl Ursolate, Stigmasterol, β-Sitosterol, Galangustin, Coumarin-O-β-glycoside and Acteoside were isolated. Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1D and 2D NMR, chemical transformation and comparison with the related known compounds. This is the first report of occurrence of these compounds in S. undulate ssp. deliciosa. The methanol extract of the roots of S. undulata ssp. deliciosa was examined for in vitro antioxidant properties using DPPH test (radical scavenging). .