ISOLATION OF SECONDARY METABOLITES AND CHEMICAL TRANSFORMATION OF CYCLIC DIARYLHEPTANOID FROM GARUGA PINNATA (BURCERACEAE)

• Main Author: Rohaeni, Sri
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/55109
• Institution: Institut Teknologi Bandung

Numerous plants from Indonesian tropical forests are widely used as medicinal plants. There is a relationship between the use of plants as medicines and their secondary metabolites. One of the medicinal plants in Indonesian tropical forest is Garuga genus. Garuga belongs to the Burseraceae family which has about 615 species and spreads across Indonesia, Malaysia, the Philippines, Papua New Guinea, India, Bangladesh, North Australia and America. The main secondary metabolites from this genus is cyclic diarylheptanoid which have various bioactivities such as anticancer, antibacterial, antioxidant, antiulcer, antimalarial, and antidiabetic. Garuga pinnata is a species of Garuga growing in Indonesia. Cyclic diarylheptanoids from G. pinnata have been reported from Bangladesh, India and American researcher, however research on G. pinnata in Indonesia has never been carried out. Therefore, isolation of secondary metabolites from G. pinnata stem bark, and chemical transformation of the dominant compound were conducted in this research. The research has been begun by the isolation of of secondary metabolites from the stem bark of G. pinnata. The isolation has been carried out by several steps. First, the stem bark powder was extracted in room temperature (maceration) by using acetone to get acetone extract. Next, the acetone extract was further fractionated and purified by using several chromatography methods, such as Vacuum Liquid Chromatography (VLC), Radial Chromatography (RC) and Gravitational Column Chromatography (GCC). Determination of the structure of isolated compounds has been conducted according to spectroscopic data, i.e. 1D-NMR (1H-NMR and 13C-NMR) and 2D-NMR (HSQC and HMBC). Nine pure compounds have been isolated from acetone extract of G. pinnata stem bark including three new compounds i.e. GP3, GP8, and GP11. Whereas, three known a diphenyl ether type cyclic diarylheptanoids have been identified as garuganin I, garuganin III, and 9’-desmethylgarugamblin I along with three known a biphenyl type cyclic diarylheptanoids identified as garuganin II, Gf-3 and alnusdiol. Garuganin II was the dominant compound found in the stem bark of G. pinnata (133 mg of 700 grams dry bark powdered). Therefore, two transformation reactions, allylation and prenylation reactions, were carried out on garuganin II in this research. The allylation reaction of garuganin II produced one major compound (RA) and the prenylation reaction produced one major compound (RP) with a yield of 42,6% dan 28,4%, respectively.