Alangiside isolation

The structure of the monoterpenoid alkaloid alangiside (115 R = H) has been confirmed by synthesis of the O-methyl ether (115 R = Me) from secologanin and 3-hydroxy-4-methoxyphenethylamine 202 the isolation of loganic acid from the same plant (Alangium lamarckii) is consistent with biosynthetic theory. 

Details have appeared of the isolation and structural elucidation of alangiside (174 R = Me, = H) (c/. Vol. 3). The location of the free phenolic hydroxy-group is based on the non-identity of the alkaloid with a sample of its isomer (174 R = H, R = Me) synthesized from secologanin/ ... 

Nagakura s group (24) reported on the isolation of 54 and 55 from the methanolic extracts of the dried fruits of A. lamarckii. Since both compounds were obtainable (albeit in a low yield) from alangiside (18) by treatment with MeOH at room temperature for 9 months, they have been considered (24) to be artifacts arising from 18, the co-occurring alkaloid. 

Nagakura and co-workers (18) isolated ipecoside (7), alangiside (18), 6-0-methylipecoside (8), ipecosidic acid (10), demethylalangiside (19), neoipecoside (15), 7-O-methylneoipecoside (16), and 3,4-dehydroneoip-ecoside (17) (possibly an artifact) from the roots of C. ipecacuanha. 

Alangiside C25H31NO10 [ ]d- 105° (MeOH) was isolated from the roots, leaves, and fruit of Alangium lamarckii Thw. (Alangiaceae). However, the best source was found to be the unripe fruit. The UV spectrum... 

Emetine and Related Alkaloids.—A review on the ipecac alkaloids has ap-peared. (— )-Alangiside (208) is a terpenoidal lactam recently isolated from Alangium lamarckii Thw. (Alangiaceae). The structure was proven by chemical correlation with desacetylipecoside (209) (Scheme 13). ... 

No new alkaloids in this series have been isolated. However, the structure of ankorine has been revised and that of alangiside has been established with certainty. ... 

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