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This study was aimed to prepare polyeugenol with high molecular weight and to evaluate its antibacterial and antioxidant activities. First, polyeugenol was synthesized from eugenol in the presence of H2SO4-CH3COOH (4:1) as catalyst. The synthesized polyeugenol was weighed by using viscometer, revealing its high molecular weight of (7.76–21.9) × 105 g/mol. Furthermore, the antibacterial activity of the polyeugenol was conducted against Staphylococcus aureus and Escherichia coli bacteria. It was conducted by applying well diffusion method at 1, 2, 3, 4 and 5% concentrations to observe inhibition zones, in which the tests showed that the antibacterial activity of the polyeugenol against S. aureus were 17.42, 17.76, 18.79, 21.42 and 22.55 mm, while those against E. coli were 15.87, 17.23, 17.56, 18.24 and 19.21 mm, respectively. In short, these results indicated a strong antibacterial activity. Then, tests on antioxidant activity against free radical DPPH (2,2-diphenyl-1-pycrylhydrazyl) gave the IC50 value of 80.47 µg/mL, indicating a strong antioxidant activity. Therefore, the polymer synthesized in this work has a high potential to be applied in various biomedical applications.

Three stigmastane steroids: 6-hydroxystigmast-4-en-3-one (1), stigmast-4-en-3-one (2), and 3-hydroxystigmast-5-en-7-one (3) were successfully isolated from the acetone extract of Dryobalanps oblongifolia stem bark. The structural determination of isolated compounds was carried out on the basis of data analysis of NMR and MS spectra. In order to identify the antiplasmodial activity, the isolated compound was put to test against Plasmodium falciparum 3D7. Antiplasmodial activity of the isolated compounds showed that the IC50 values of 6-hydroxystigmast-4-en-3-one were 37.29 μg/mL while the IC50 values of stigmast-4-en-3-one were 43.54 μg/mL and the IC50 values of 3-hydroxystigmast-5-en-7-one were 13.34 μg/mL (chloroquine phosphate was used as a positive control, IC50 0.006 μg/mL). Judging from the results, the isolated compounds were proven to demonstrate mediocre antiplasmodial activity. Compound (3) indicated a better antimalarial activity than compound (1) and (2), even though there was no satisfactory activity that indicated its ability to combat chloroquine. Therefore, it might not be developed as an antimalarial drug.

A new compound belonging to a dihydrotetrazolopyrimidine derivative, that is, ethyl 5-methyl-7-(4-morpholinophenyl)-4,7-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylate, was successfully synthesized using a Biginelli reaction between 4-morpholinobenzaldehyde, ethyl acetoacetate, and 5-aminotetrazole with p-toluenesulfonic acid (pTSA) as a catalyst in ethanol under reflux. The molecular structure of the title compound was characterized on the basis of spectroscopic evidence, using FTIR, HRESI-MS, 1H- and 13C-NMR, and 2D NMR.

A new compound belonging to the “heterostilbene” derivative, namely ethyl (E)-4-(2,4-dimethoxyphenyl)-6-(2,4-dimethoxystyryl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (2), has been successfully synthesized as an unprecedented side product of the Biginelli reaction between 2,4-dimethoxybenzaldehyde, ethyl acetoacetate and urea, employing PTSA as catalyst in reflux conditions and using ethanol as solvent. The molecular structure of compound (2) was established by FTIR, HRESIMS, 1D and 2D NMR.

The research about synthesis and characterization of chiral compounds from the rough methyleugenol with acetic acid as the catalyst has been done. The goal is to determine the content of 1-(3,4-dimetoksifenil)-2-propanil acetate compound which is produced in the reaction process of metileugenol with acetic acid and to characterizased the chemical compound of the product. The results showed that the content of 1-(3,4-dimetoksifenil)-2-propanil acetate compound that has been obtained was 45.87% with a molecular weight of 238.Keywords : Methyleugenol, Chiral, FT-IR, GC-MS

Infectious disease is one of sources of high morbidity and mortality caused by bacteria. Artocarpus plant is biosource to discover compounds with interesting bioactivites. The objective of this study is to find antibacterial compound from nature by extraction, fractionation, identification, and antibacterial test of secondary metabolite from dichloromethane extract of Artocarpus dasyphylla tree bark. The dichloromethane extract was fractionated repeatedly using various chromatographic techniques. The secondary metabolite was identified of its molecular structure based on UV-Vis, IR, NMR spectral data and confirmed by comparation with the reference. The secondary metabolite was known as catechin or 5,7,3’,4’-tetrahydroxyflavan-3β-ol. Antibacterial testing of cathecin against Escherechia coli and Staphylococcus aureus showed a low antibacterial activity.

A one-pot multicomponent reaction has been used to synthesize the title compound, ethyl 4-[5-(methoxymethyl)furan-2-yl]-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate by PTSA catalyzed Biginelli reaction. The chemical structure of the product was confirmed by spectroscopic evidence, FTIR, HRESI-MS, 1D-, and 2D NMR.