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"ABSTRAKVanili, selain dapat diperoleh dengan cara isolasi dari buah vanila,juga dapat dihasilkan dengan cara sintesis. Salah satu cara sintesis vanili yaitu melalui reaksi Reimer-Tiemann dengan substrat guaiakol dan pereaksinya kloroform. Guaiakol tersebut akan diubah menjadi ion guaiakolat oleh larutan KOH alkoholis yang ditambahkan, sedangkan kloroform oleh gugus hidroksida akan diubah menjadi diklorokarbena , setelah itu baru terjadi reaksi antara ion guaiakolat atau guaiakol dengan diklorokarbena.Guaiakol pada penelitian ini diperoleh dengan cara sintesis dari pirokatekol, melalui serangkaian tahap reaksi yang terdiri dari benzoilasi, metilasi dan hidrolisis dalam suasana basa, dan diperoleh hasil dengan rendemen 52%. Disamping itu dicoba juga dengan cara lain yaitu asetilasi,metilasi dan hidrolisis dalam suasana basa , dan diperoleh hasil dengan spektrum yang kurang jelas, maka dengan cara ini dianggap gagal. Metilasi dalam penelitian ini dilakukan dengan diazometana.Penelitian ini bertujuan untuk memberi nilai tambah pirokatekol dan guaiakol serta mengoptimalisasi reaksi Reimer-Tiemann dengan cara penambahan katalis transfer fasa tetrabutil amonium perkiorat , tetrametil amonium yodida dan 18-crown eter-6 ,pada suhu 45°C dengan putaran 1000 rpm selama 4 jam. Dengan menggunakan katalis transfer fasa tetrabutil amonium perkiorat dapat mencapai rendemen 65,8% , sedangkan dengan katalis tetrametil amonium iodida 51,4% dan katalis 18-crown ether-6 sebesar 27,9%.

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ABSTRACT

One method of synthesis vanillin is via Reimer-Tiemann reaction with substrate guaiacol and chloroform reagent, chloroform .will be converted bit hydroxy ion to dichlorocarbene and then reaction with guaiacol solution.

Guaiacol in this research is obtained from pyrocathecol, via step reactions : benzoilation, methylation and hydrolysis in base conditions and product has yield 52%. Synthetic of guaiacol from pyrocathecol via step acetylation reaction is failure.

The aim of this research is to increase value on pyrocathecol, guaiacol and optimalization Reimer-Tiemann reaction with phase transfer catalysts : tetrabutyl ammonium perchlorate (TBAP), tetramethyl ammonium iodidate (THAI) and 18-crown ether-6 (18C6) at temperature 45°C and 1000 rpm for 4 hours. Yield of reactions with TBAP, THAI and 18C6 catalysts are 65,6%, 51,4% and 27,9%, respectively."

"Kelapa sawit sebagai sumber energi terbarukan dapat diproses menjadi biooil yang nantinya dapat dijadikan bahan bakar alternatif pada kendaraan bermotor. Kelapa sawit sebagai umpan dicacah hingga diameter 0,1-2 mm, selanjutnya umpan diproses menggunakan metode fast pyrolysis, dan yang terakhir dilakukan pengujian pada produk cair. Penelitian ini menggunakan variasi bahan baku kelapa sawit (cangkang, tandan, dan serat) dengan kondisi suhu operasi 450, 550, dan 650°C. Faktor utama yang mempengaruhi jumlah biooil adalah komposisi biopolimer umpan. Jumlah kandungan biopolimer dari masing-masing umpan adalah : cangkang 94,2%; tandan 90%; dan serat 80%. Sesuai dengan banyaknya kandungan biopolimer, hasil dari eksperimen didapat bahwa umpan cangkang menghasilkan biooil dengan jumlah terbesar (62% pada suhu optimum 550°C) disusul oleh tandan (58% pada suhu optimum 550°C) dan serat (38% pada suhu optimum 650°C)

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Palm oil waster as a source renewable energy can be processed into biooil that can later be used as alternative diesel fuels. Palm oil waste is crushed up to diameter 0,1-2 mm, then feed from palm oil waste is processed using fast pyrolysis method to produced biooil, and latter liquid product is carried out for tests. This study uses variation of raw material palm oil waste (EFB, shell, and fiber) with operating temperature conditions of 450, 550, and 650°C.

Biopolimer content is the main factor that can influence the quantitiy of liquid product. Quantitiy of biopolimer content from each feedstock are: shell 94,2%; EFB 90%; and fiber 80%. In accordance with the quantity of biopolimer content, the results from experiments showed that shell produces biooil with largest number (62% at the optimum temperature of 550°C), followed by EFB (58% at the optimum temperature of 550oC), and fiber (38% at the optimum temperature of 650°C) "

"Keladi tikus (Typhonium flagelliforme (Lodd) Blume merupakan herba yang secara tradisional digunakan sebagai antikanker. Tujuan penelitian adalah mengetahui kandungan senyawa kimia ekstrak metanol dari daun T. Flagelliforme. Isolasi senyawa dilakukan dengan cara maserasi, dilanjutkan dengan pemisahan sesuai dengan kepolarannya dan diuji aktivitas antioksidan, aktivitas antimikroba dan uji bioaktivitas terhadap larva A.salina Leach. Fasa aktif sebagai antioksidan, antimikroba dan toksisitas terhadap A.salina ditunjukkan oleh fasa etil asetat dengan nilai IC50 56,32 μg/mL, diameter hambatan 16,2 mm (Pseudomonas aeruginosa) dan 18,1 mm (Bacillus subtilis) dan LC50 54,82 μg/mL. Uji sitotoksisitas terhadap sel kanker T-47D dan sel murine leukemia P388 juga dilakukan terhadap fasa aktif tersebut. Pemisahan lanjutan dari fasa aktif dilakukan melalui kromatografi cair vakum (SiO2, diklormetana, isopropanol~ metanol) secara gradien dan kromatografi kolom (LH20, metanol). Pemurnian secara kromatografi cair kinerja tinggi preparatif kolom C18 dengan eluen metanol-air secara gradien. Penentuan struktur molekul dengan menganalisis data spektrum UV-Vis, FTIR, LC-MS MS, 1H-NMR, 13C-NMR, dan 2D-NMR. Hasil isolasi terhadap fasa etil asetat T. flagelliforme (Lodd) Blume diperoleh 3 senyawa yaitu adenin, adenosin dan 6-C-glukopiranosilapigenin. Ketiga senyawa tidak aktif terhadap sel kanker T-47D namun menunjukkan aktivitas terhadap sel murine leukemia P-388 masing-masing dengan nilai IC50 71,36; 87,26 dan 34,41 μg/mL, sedangkan senyawa 6-C-glukopiranosilapigenin memiliki aktivitas antioksidan dengan nilai IC50 34,39 ug/mL serta toksisitas terhadap larva A.salina dengan nilai LC50 15,84 μg/mL. Semua nilai aktivitas tersebut masih lebih kecil dibandingkan kontrol masing-masing.

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Keladi tikus (T. flagelliforme (Lodd)Blume ), is a medicinal herb which traditionally used as anticancer. The aim of study was to determine chemical compounds of the methanol extract. The isolation of compound was carried out by maceration, followed by separation according to polarity. The ethyl acetate as active phase showed the antioxidant activity with IC50 value of 56.32 μg/mL, the antimicrobial activity with inhibiton zone 16.2 mm (Pseudomonas aeruginosa) and 18.1 mm (Bacillus subtilis), and bioactivity against A.salina Leach larvae with LC50 value of 54.82 μg/mL. The cytotoxicity against T-47D cancer cells and P.388 leukemia cells also was carried out to the active phase. The separation and purification were conducted by VLC (SiO2, dichloromethane-isopropanol, ~ methanol) using gradient elution and column chromatography (LH20, methanol) and HPLC preparative with C18 column methanol-water as eluent. Molecule structure determination was analyzed using the UV-Vis spectral data, FTIR, LC-MS MS, 1D NMR, 2D NMR. The result from the active phase obtained three compounds namely adenine, adenosine and 6-C-glucopyranosylapigenin. All three compounds were not active against T-47D cancer cells but they showed activity against P-388 leukemia cells with IC50 values of 71.36; 87.26 and 34.41 μg/mL respectively, while 6-Cglucopyranosylapigenin compound showed antioxidant activity with IC50 value of 34.39 μg/mL and toxicity against A.salina with LC50 value of 15.84 μg/mL. All the values of activity however are still lower compare to the relevant compound as control."

"Provides the background, tools, and models required to understand organic synthesis and plan chemical reactions more efficiently Knowledge of physical chemistry is essential for achieving successful chemical reactions in organic chemistry. Chemists must be competent in a range of areas to understand organic synthesis. Organic Chemistry provides the methods, models, and tools necessary to fully comprehend organic reactions. Written by two internationally recognized experts in the field, this much-needed textbook fills a gap in current literature on physical organic chemistry. Rigorous yet straightforward chapters first examine chemical equilibria, thermodynamics, reaction rates and mechanisms, and molecular orbital theory, providing readers with a strong foundation in physical organic chemistry. Subsequent chapters demonstrate various reactions involving organic, organometallic, and biochemical reactants and catalysts. Throughout the text, numerous questions and exercises, over 800 in total, help readers strengthen their comprehension of the subject and highlight key points of learning. The companion Organic Chemistry Workbook contains complete references and answers to every question in this text"

"Provides the background, tools, and models required to understand organic synthesis and plan chemical reactions more efficiently Knowledge of physical chemistry is essential for achieving successful chemical reactions in organic chemistry. Chemists must be competent in a range of areas to understand organic synthesis. Organic Chemistry provides the methods, models, and tools necessary to fully comprehend organic reactions. Written by two internationally recognized experts in the field, this much-needed textbook fills a gap in current literature on physical organic chemistry. Rigorous yet straightforward chapters first examine chemical equilibria, thermodynamics, reaction rates and mechanisms, and molecular orbital theory, providing readers with a strong foundation in physical organic chemistry. Subsequent chapters demonstrate various reactions involving organic, organometallic, and biochemical reactants and catalysts. Throughout the text, numerous questions and exercises, over 800 in total, help readers strengthen their comprehension of the subject and highlight key points of learning. The companion Organic Chemistry Workbook contains complete references and answers to every question in this text"