Alkaloids and Styryl Lactones from Goniothalamus tortilipetalus and Their Biological Activities

Abstract

Phytochemical investigations of the twig and leaf extracts of Goniothalamus tortilipetalus resulted in the isolation and identification of two new alkaloids, goniotortiline (1) and goniotortilactam (2), three new styryl lactone derivatives, goniotortilactone (3) and goniotortilols A (4) and B (5), and 25 known compounds. Their structures were elucidated by spectroscopic methods and HRESITOFMS data. Compounds 5, 13, 15, 16, 22, and 30 inhibited nitric oxide (NO) production with IC₅₀ values ranging from 8.7 ± 0.1 to 17 ± 1 μM, revealing stronger effects than the standard drug, dexamethasone (IC₅₀ 16.9 ± 2.2 μM), and compound 30 possessed the most potent NO production inhibition. Compounds 12 and 29 demonstrated notable efficacy in enhancing glucose consumption with IC₅₀ values of 77 ± 4 and 66 ± 4 μM, respectively, while their glucose uptakes were 1.7- and 2-fold, respectively.

1

1

Key ¹H–¹H COSY and HMBC correlations of compounds 1–5 and the X-ray ORTEP-like diagram of 1.

2

Key NOESY correlations of compounds 3–5.

3

Experimental and calculated ECD spectra of compound 3.

4

Experimental and calculated ECD spectra of compound 4.

5

Experimental and calculated ECD spectra of compound 5.