A new nitrogen-containing iridoid glycoside from lonicera macranthoides

Abstract

A new nitrogen-containing iridoid glycoside, named (7 R,3′R)-lonijapospiroside A (1), together with thirteen known iridoid glycosides, were isolated from the flower buds of Lonicera macranthoides. The structures of these compounds were established on the basis of spectroscopic analyses. Among them, compounds 1-4 are four diastereoisomers, and their absolute configurations were accurately established by the NOE spectra as well as comparison of their experimental and calculated ECD spectra. The anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on NO, IL-6, and TNF-α production in LPS stimulated RAW 264.7 macrophages. Compound 14 exhibited anti-inflammatory activities by inhibiting IL-6 with an IC₅₀ value of 54.70 μM, comparable to that of the positive control (hydrocortisone, IC₅₀: 62.6 ± 1.7 μM).

Graphical Abstract

Keywords:

• Lonicera macranthoides
• iridoid glycoside
• anti-inflammatory
• NO
• IL-6
• TNF-α

Acknowledgements

The authors are grateful to State Key Laboratory of New-Tech for Chinese Medicine Pharmaceutical Process, Jiangsu Kanion Pharmaceutical Co. Ltd. for their assistance of activity test.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 The record derives from WCSP which reports it as a synonym with original publication details: Symb. Sin. 7: 1050 1936.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China (program No. 81630097, 81602984 and 81803347), National Major Scientific and Technological Special Project for “Significant New Drugs Development” during the Thirteen Five-year Plan Period (2018ZX09711001-008-005).