Aspertins A-D: Further Piperidine Alkaloids from Andrachne aspera (Euphorbiaceae)
نویسندگان
چکیده
Andrachne aspera, a small perennial undershrub, is commonly found in the arid, stony and sandy regions of Pakistan. Medicinally, this plant is used to improve eyesight and to treat eye sores2−3. A crude alkaloidal mixture has been reported to show various biological activities. The biological significance of A. aspera motivated us to reinvestigate for further alkaloidal constituents fourteen years later5−6. The plant material was again collected from the same site (Karachi University campus). Unfortunately, it was not possible to obtain sufficient amounts of aspertins A-D for biological screening. The present communication deals with the isolation and structure elucidation of four new alkaloids (aspertins A-D) using NMR and mass spectrometric techniques.
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