A new steroidal glycoside from the seeds of Hyoscyamus niger
A new steroidal glycoside hyoscyamoside G (1), together with two known analogues hyoscyamoside E (2) and hyoscyamoside F1 (3), was isolated from the seeds of Hyoscyamus niger. The structure of 1 was established as (22R,24Z)-1α,3β,7β,22,26-pentakishydroxylergost-22-O-β-d-gulcopyranosyl-5,24-diene-26-O-β-d-glucopyranoside, by means of chemical and spectroscopic methods including HRESI-MS, 1D and 2D NMR. In vitro, compound 2 showed cytotoxicity against human lung cancer cell H460 with IC50 value of 66 μg/mL.
Chemical and Pharmacological Researches on Hyoscyamus niger
The reports on chemical constituents of Hyoscyamus niger were summarized. The compounds include alkaloids, saponins, lignans, coumarinolignans, flavonoids, and some other nonalkaloidal compounds. TLC, HPLC, and GC were used for the qualitative and quantitative analyses of some chemical constituents in H. niger. Modern pharmacological experiments showed that H. niger had the analgesic, anti-inflammatory, antipyretic, anticonvulsant, spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory, urinary bladder relaxant, hypotensive, cardiosuppressant, vasodilator, antitumor, and feeding deterrent properties. In addition, the toxicities of this medicinal plant were also described.
Geomagnetic Polarity Epochs: Sierra Nevada Data, 3
Available paleomagnetic and radiometric results for about 60 igneous rocks 3.6 m.y. old or less are consistent with the following geomagnetic polarity epoch time scale: Brunhes normal polarity epoch, 0.0 to 0.85±0.15 million years; Matuyama reversed polarity epoch, 0.85±0.15 to 2.4±0.1 million years; Gauss normal polarity epoch, 2.4±0.1 to 3.35±0.1 million years; Gilbert reversed polarity epoch, 3.35±0.1 million years to (?). A brief interval of normal polarity (the Olduvai event) occurs within the Matuyama reversed epoch at about 1.9 m.y., and a brief interval of reversed polarity (the Mammoth event) occurs within the Gauss normal epoch at about 3.06 m.y. Data for twelve units from eastern California and Nevada, reported here for the first time, are particularly useful in defining the Gauss-Gilbert boundary and for recognizing the Mammoth event.