Three new phenylpropanoid glucosides and a new tyramine-type alkamide from Piper puberulum

Abstract

Three new phenylpropanoid glycosides, piperpubelide (1), 1-propionyl-3-hydroxy-phenyl-4-O-β-D-glucopyranoside (2), and 1-propionyl-4-hydroxy-phenyl-3-O-β-D-glucopyranoside (3), a new tyramine-type alkamide, puberulumine L (4), together with thirteen known compounds (5−17) were isolated from Piper puberulum (Benth.) Maxim. Their structures were elucidated by analysis of spectroscopic data involving NMR, IR, UV, and HRESIMS data. Calculated and experimental ECD was used to confirm the configuration of compound 1. Compounds 14, 16, and 17 exhibited relatively positive DPPH radical scavenging activities, with corresponding EC₅₀ of 10.23, 24.12, and 21.83 μM, respectively. In addition, compound 5 inhibited LPS-induced NO production in BV-2 microglia with an IC₅₀ value of 18.05 μM.

Keywords:

• Piperaceae
• Piper puberulum
• phenylpropanoid glycoside
• tyramine-type alkamide
• piperpubelide

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (81960634), the project of the State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (CMEMR-2020A06; CHEMR2023-A01), the National Administration of Traditional Chinese Medicine (No. GZYYGJ2020023), and the Higher Education Commission of Pakistan (NRPU 2021 #17603).