Unexpected Dimer from Demethylization Reaction of Eugenol under Acidic Conditions

Eugenol is an alkenyl phenol compound obtained as an essential oil from different parts of the clove such as its leaves and flowers. The essential oil from cloves can contain up to 90% eugenol, which is mainly responsible for its aroma. Eugenol is an interesting compound due to its simplicity and richness in functionalities, making it a valuable building block in synthesis. One of the key steps in eugenol transformation is demethylation to produce a hydroxycavicol. Demethylation is commonly carried out using a nucleophilic or an acidic method. In this study, a simple yet reliable nucleophilic method for demethylation using lithium chloride (LiCl) was attempted. The product was characterized by NMR, FTIR and HRMS spectroscopy. The absence of a methoxy signal at 3.5-4 ppm in the 1H NMR spectrum suggests that demethylation was successful. The HRMS result showed m/z 149.0596, confirming the formation of product. The demethylation reaction under acidic conditions formed a dimer of eugenol with the methoxy group still intact. This was supported by the 1H NMR data, which showed methoxy signals at 3.85 and 3.82 ppm and integration in the aromatic region, which suggests a dimer structure

Optimization of the Drying Method of Red Fruit (Pandanus conoideus Lam) by Detente Instantanee Controlee (DIC)

The development of process engineering and the finding of plant-based new medicines are growing very fast. Pandanus conoideus Lam, an indigenous fruit plant in Irian Jaya, the eastern province of Indonesia is one of the well-known herbal plants. "Buah Merah" (Indonesian), meaning red fruit due to the bright red color of the main variety, is well known as a medicinal plant traditionally used as anti-cancer, anti diabetic, anti dislipidemia, anti-oxidant agent, etc., whose effects greatly depend on its total phenol, flavonoids, tocopherols, carotenoids, vitamins content, etc. Good-quality herbal medicine should be a phyto-pharmaceutical product, which requires certain prerequisites to obtain standardized extract or powder form. Good extract quality normally involves a well dried raw material in order to minimize the enzymatic and hydrolytic reactions. In this study, the effect of pre drying by Detente Instantanee Controlee(DIC) method is studied, as it opens up the plant cells' pores, so that the vaporization will be accelerated; and the thermal degradation is reduced. Thirteen operating parameters of DIC have been studied. The results showed that maximum moisture content reduction for a drying time of 180 minutes, of DIC-15 (0.2 MPa steam pressure, 3 cycles of 20 seconds each) was of 94.58%, and of DIC-16 (0.25 MPa, 4 cycles of 15 seconds, each) was 91.24%, which a/so produced 3.21% Catechin Equivalent (CE) and 6.44% Gallic Acid Equivalent (GAE), respectively. They were higher than those obtained from the conventionally-dried (CD) fruits without and after juice extraction which produced 2.61% and 1.13% CE, and 4.58% and 2.57% GAE, respectively. DIC pretreatment was also able to enhance cttocopherol extraction compared to those of CD red fruits (after juice extraction); and the DIC-19 (0.15 MPa, 2 cycles of 15 seconds, each) extract produced 3,2750.5 mg ct-tocopherol /kg extract, although the yield of the CD fruit extract without juice extraction was 6,631.95 mg/kg extract. This research is a collaboration between the fields of Engineering and Pharmacy

Development of new synthetic methodologies and their application towards synthesis of natural products

The thesis consists of four parts: 1. Development of methodology namely indium (III) chloride catalyzed Mukaiyama-Michael addition for the construction of 2,6-anti pyran. 2. Application of indium (III) chloride catalyzed Mukaiyama-Michael addition in the total synthesis of polyrachitide A. 3. Application of indium (III) chloride catalyzed Mukaiyama-Michael addition in the total synthesis of apicularen A. 4. Synthetic studies towards marinomycins, a potential antitumor-antibiotic macrolide isolated from the marine sponges.DOCTOR OF PHILOSOPHY (SPMS

Synthesis and Characterization of Titanium Oxide in 1-Butyl-3-Methyl Immidazolium Chloride Ionic Liquid by Hydrothermal Method

Pada penelitian ini dilakukan sintesis TiO2 dengan metode hidrotermal dimana pelarut yang digunakan adalah campuran cairan ion 1-butil-3-metil imidazolium klorida (BMIM Cl) dan air dengan perbandingan 3:7 v/v. Cairan ion 1- butil-3-metil imidazol disintesis dengan prekursor metil imidazol dan klorobutana kemudian dikarakterisasi menggunakan NMR 43 MHz. TiO2 yang telah disintesis dengan pelarut BMIM Cl : air (3:7 v/v) kemudian dikarakterisasi menggunakan XRD, SEM, UV-Vis/DR dan BET serta dibandingkan hasilnya dengan TiO2 yang disintesis dengan pelarut air. Hasil analisis XRD diperolah bahwa pada sintesis TiO2 baik dengan pelarut air maupum BMIM Cl : air (3:7 v/v) menghasilkan kristal anatase dan brokit dimana ukuran kristal TiO2yang disintesis dengan pelarut BMIM Cl : air (3:7 v/v) lebih kecil yaitu 17,70 nm dan yang disintesis dengan pelarut air sekitar 20,35 nm. Berdasarkan data karakterisasi SEM diperoleh struktur morfologi yang lebih homogen pada TiO2 yang disintesis dengan pelarut BMIM Cl : air (3:7 v/v). Karakterisasi menggunakan UV-Vis/DR dan BET diperoleh bahwa TiO2 yang disintesis dengan BMIM Cl : air (3:7 v/v) memiliki band gap yang lebih besar dan luas permukaan serta pori yang lebih besar dibandingkan dengan TiO2 yang disintesis dengan pelarut air.In this study, TiO2 was synthesized using the hydrothermal method which the solvent used was a mixture of 1-butyl-3-methyl imidazolium chloride ion (BMIM Cl) with water in a ratio of 3:7 v/v. Ionic liquid of 1-butyl-3-methyl imidazole was synthesized with methyl imidazole and chlorobutane as precursors and then characterized using 43 MHz NMR. TiO2 which had been synthesized with BMIM Cl : water (3:7 v/v) was then characterized using XRD, SEM, UV-Vis/DR and BET then compared the results with TiO2 synthesized with water solvent. Based on of XRD analysis was obtained that TiO2 was synthesized by BMIM Cl : water (3:7 v/v) and water solvent produced anatase and brochite crystals where the crystal size of TiO2 synthesized with BMIM Cl : water (3:7 v/v) as solvent was smaller that is 17.70 nm and which is synthesized with water solvent is about 20.35 nm. Based on the SEM characterization data, the morphological structure was more homogeneous. Based on the characterization data using UV-Vis/DR and BET, it was obtained that TiO2 synthesized with BMIM Cl : water (3:7 v/v) had a bigger band gap and larger surface area and pores than TiO2 synthesized by water solvent

Recent Developments of Liquid Chromatography Stationary Phases for Compound Separation: From Proteins to Small Organic Compounds

Compound separation plays a key role in producing and analyzing chemical compounds. Various methods are offered to obtain high-quality separation results. Liquid chromatography is one of the most common tools used in compound separation across length scales, from larger biomacromolecules to smaller organic compounds. Liquid chromatography also allows ease of modification, the ability to combine compatible mobile and stationary phases, the ability to conduct qualitative and quantitative analyses, and the ability to concentrate samples. Notably, the main feature of a liquid chromatography setup is the stationary phase. The stationary phase directly interacts with the samples via various basic mode of interactions based on affinity, size, and electrostatic interactions. Different interactions between compounds and the stationary phase will eventually result in compound separation. Recent years have witnessed the development of stationary phases to increase binding selectivity, tunability, and reusability. To demonstrate the use of liquid chromatography across length scales of target molecules, this review discusses the recent development of stationary phases for separating macromolecule proteins and small organic compounds, such as small chiral molecules and polycyclic aromatic hydrocarbons (PAHs)