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Structure determination of bioactive galloyl derivatives by NMR spectroscopy

✍ Scribed by Viqar Uddin Ahmad; Muhammad Zubair; Muhammad Athar Abbasi; Muhammad Abid Rashid; Nasir Rasool; Shamsun Nahar Khan; M. Iqbal Choudhary; Farzana Kousar

Publisher
John Wiley and Sons
Year
2005
Tongue
English
Weight
98 KB
Volume
43
Category
Article
ISSN
0749-1581

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✦ Synopsis

The investigation of the chemical constituents of Symplocos racemosa

Roxb led to the isolation of two new glycosides, symcomoside A (1) and symcomoside B (2), together with one known glycoside, tortoside C (3), which is reported for the first time from this plant. The structures of the new compounds were determined by 1D and 2D homonuclear and heteronuclear NMR spectroscopy, from chemical evidence and by comparison with published data for closely related compounds. Symcomoside B (2) showed potent inhibitory activity against a-glucosidase in a concentration-dependent fashion with an IC 50 value of 0.733 ± 0.033 mM whereas symcomoside A (1) showed very weak inhibitory activity against aglucosidase (9.90% in 0.70 mM).

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