Polyacetylenes from the Roots of Swietenia macrophylla King.

Cheng-Neng Mi,Hao Wang,Wen-Li Mei,Hui-Qin Chen,Hao-Fu Dai,Shao-Peng Li,Cai-Hong Cai

doi:10.3390/molecules24071291

Abstract

A phytochemical investigation of the roots of Swietenia macrophylla led to the isolation of seven polyacetylenes, including five new compounds (1–5) and two known ones (6–7). Their structures were elucidated by extensive spectroscopic analysis and detailed comparison with reported data. All the isolates were tested for their cytotoxicity against the human hepatocellular carcinoma cell line BEL-7402, human myeloid leukemia cell line K562, and human gastric carcinoma cell line SGC-7901. Compounds 1 and 6 showed moderate cytotoxicity against the above three human cancer cell lines with IC50 values ranging from 14.3 to 45.4 μM. Compound 4 displayed cytotoxicity against the K562 and SGC-7901 cancer cell lines with IC50 values of 26.2 ± 0.4 and 21.9 ± 0.3 μM, respectively.

Highlights

Natural polyacetylenes, structures featuring two or more triple bonds [1], are mainly found in plants belonging to the Araliaceae [2,3,4,5,6,7], Asteraceae [8,9,10], Umbelliferae [11,12,13], Santalaceae [14], Pittosporaceae [15], and Oleaceae [16] families
Macrophylla resulted in the isolation and identification of five new polyacetylenes (Figure 1), respectively named heptadeca-9-ene-4,6-diyne-3,11-diol (1), (E)-heptadeca-8-ene-4,6-diyne-3,10,11-triol
(2), 10-methoxyheptadeca-4,6-diyne-3,9-diol (3), tetradeca-1,3-diyne-6,7,8-triol (4) and 6,7,8,9tetraacetoxytetradeca-1,3-diyne (5), together with two known compounds, which were identified as α-hexy-3-(6-hydroxy-2,4-ocadiynyl)oxiranemethanol (6) [17] and (3R,8E,10S)-heptadec-8-ene-4,6diyne-3,10-diol (7) [18] by comparing their experimental spectroscopic data with the reported data in the literature

Summary

Introduction

Structures featuring two or more triple bonds [1], are mainly found in plants belonging to the Araliaceae [2,3,4,5,6,7], Asteraceae [8,9,10], Umbelliferae [11,12,13], Santalaceae [14], Pittosporaceae [15], and Oleaceae [16] families. Diverse polyacetylene structures exhibit a series of bioactivities, including cytotoxicity [8,10,11,21] and antimicrobial [14,22,23], antiviral [24], and enzyme-inhibitory [6,25] activities. Antecedent chemical investigations on S. macrophylla have focused mostly on the aboveground parts and their bioactive limonoids [30]. Our recent study on the roots of S. macrophylla led to the isolation of a series of xanthones, limonoids, and other chemical components [32,33]. As a continuation of our studies on the biologically active agents from this plant, five new and two known acyclic C18 –C14 polyacetylenes have been further isolated here, and their cytotoxic activities against the human hepatocellular carcinoma. The isolation, structural elucidation, and cytotoxicity of these compounds are reported as follows

Results and Discussion

General Experimental Procedures

Plant Material

Extraction and Isolation

Bioassay of Cytotoxic Activity

Conclusions