Structure of thalicmidine
The alkaloid thalicmidine isolated from the roots of Thalictrum minus by S. Yu. Yunusov and N. N. Pmgressov [1] contains three methoxy groups and one hydroxy group (broad band in the IR spectrum at 3200-3500 cm-~). The UV spectrum of thalicmidine has three maxima at 220, 280, and 305 mg (tog e 4.52, 4.12, 4.12), which are characteristic for 2, 3, 5, 6-tetrasubstituted aporphins [2]. Methylation of thalicmidine has given glaucine (Ia) and oxidation has yielded m-hemipinic acid, Consequently, the hydroxy group must occupy position 5 or 6 [3, 4]. Since thalicmidine is not identical with glaueentrine, only position 6 remains possible for the hydroxy group (Ib).
Flavonoids in Subtribe Centaureinae (Cass.) Dumort. (Tribe Cardueae, Asteraceae): Distribution and 13C‐NMR Spectral Data
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