Stilbenes Derivatives from Cryptocarya apamifolia (Lauraceae) Dian Nugraheni, Yana Maolana Syah, Lia Dewi Juliawaty
Organic Chemistry Division, Faculty of Mathematics and Natural Sciences,
Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
Abstract
Cryptocarya is one of the large genera in the Lauraceae family. It has been used as traditional medicine, such as to cure sore eye, stomachache, cough, and diarrhea. Moreover, it economically has also value for building materials and pulps. This genus contains flavonoids, α--pyrones, and alkaloids as major compounds, along with other compounds, including stilbenes, lignans, and terpenoids. Those compounds showed various bioactivities, such as anticancer, antiviral, antiinflammatory, and anti-Alzheimer. One of the species growing in Papua is C. apamifolia which has never been reported previously, so that it has become important to study its phytochemistry and bioactivities. Therefore, the objective of this research was to isolate the secondary metabolites of the stem bark of C. apamifolia and to analyze their inhibition activity against tyrosine kinases. The isolation and purification of the compounds have been carried out through various chromatography techniques. The structures of isolated compounds were determined by analyzing data of 1D-NMR (1H and 13C), 2D-NMR (HMBC and HSQC), and compared with literature data. The bioactivity assay was performed against eight RTK^s (EGFR, HER2, HER4, InsR, KDR, VEGFR, PDGFRα-, PDGFRβ-). As a result, three known stilbenes have been isolated, identified as pinosylvin, pinosylvin monomethylether, and reflexanbene I. Stilbene compounds in Cryptocarya genus is still limited and only obtained from Indonesian species. Pinosylvin and reflexanbene I were isolated from the first time in this genus, but pinosylvin monomethyleter was once reported from C. idenburgensis. Meanwhile, reflexanbene I has been found in Lindera genus (Lauraceae) that also showed close relationship between Cryptocarya and Lindera genus in this family. Furthermore, those compounds showed moderate activity against EGFR, with their % inhibitory being 40%, 39%, and 41%, respectively. Therefore, they could potentially become tyrosine kinase inhibitor agents
