Two New Quaternary Alkaloids and Anti-Hepatitis B Virus Active Constituents from Corydalis saxicola

Abstract

Two new quaternary isoquinoline alkaloids, saxicolalines A (1) and N-methylnarceimicine (2), together with sixteen known alkaloids (3 - 18) were isolated from Corydalis saxicola Bunting. The structures of saxicolalines A (1) and N-methylnarceimicine (2) were established based on spectral methods including 1D, 2D NMR (COSY, HMQC, HMBC) and HR-ESI-MS. The anti-HBV activities of ten main alkaloids were evaluated. Among the tested compounds, dihydrochelerythrine (8) exhibited the most potent activity against HBsAg and HBeAg secretions with IC₅₀ < 0.05 μM, SI > 3.5, respectively.

Key words

Corydalis saxicola Bunting - Fumariaceae - quaternary isoquinoline alkaloids - anti-HBV activity

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