Chairil Anwar
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281

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Syntheses of Azo-Imine Derivatives from Vanillin as an Acid Base Indicator Bambang Purwono; Chairil Anwar; Ahmad Hanapi
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (963.721 KB) | DOI: 10.22146/ijc.21318

Abstract

Preparations of azo, imine and azo-imine derivatives from vanillin as an indicator of acid-base titration have been carried out. The azo derivative of 4-hydroxy-3-methoxy-5-(phenylazo)benzaldehyde 2 was produced by diazotitation reaction of vanillin in 37.04% yield. The azo product was then refluxed with aniline in ethanol to yield azo-imine derivatives, 2-methoxy-6-(phenylazo)-4-((phenylimino)methyl)phenol 1 in 82.21% yield. The imine derivative, 2-methoxy-4-((phenylimino)methyl)-phenol 3 was obtained by refluxing of vanillin and aniline mixture in ethanol solvent and produced 82.17% yield. The imine product was then reacted with benzenediazonium chloride salt. However, the products indicated hydrolyzed product of 4-hydroxy-3-methoxy-5-(phenylazo)benzaldehyde 2 in 22.15% yield. The 2-methoxy-4-((phenylimino)methyl)phenol 2 could be used as an indicator for titration of NaOH by H2C2O4 with maximum concentration of H2C2O4 0.1 M while the target compound 1 could be used as titration indicator for titration of NaOH with H2C2O4 with same result using phenolphthalein indicator.
ISOLATION ANTHOCYANIN FROM ROSELLE PETALS (Hibiscus sabdariffa L) AND THE EFFECT OF LIGHT ON THE STABILITY Siti Nuryanti; Sabirin Matsjeh; Chairil Anwar; Tri Joko Raharjo
Indonesian Journal of Chemistry Vol 12, No 2 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (358.856 KB) | DOI: 10.22146/ijc.21358

Abstract

This study was conducted to isolate anthocyanins from roselle petals and testing the stability toward light. Isolation of anthocyanin was accomplished by extracting roselle petals using eluents with different polarity levels. Nonpolar compounds was eliminated using n-hexane, then semipolar compounds extracted with ethyl acetate and isolated anthocyanin by solvent mixtures of methanol-HCl 0.5%. Color test to determine the presence of anthocyanin was performed with NH3 vapor, Pb-acetate 1% and Pb-nitrate 5%. The structure of anthocyanin in the roselle flower was determined using UV-Vis spectrophotometer, FT-IR and 1H-NMR. Anthocyanin stability test of the influence of light carried out in a room without light conditions (dark room) and light 25 Watt at 31 °C. The results showed that the roselle petals contain anthocyanin cyanidin-3-glucoside. Light has been found to affect the stability of anthocyanin cyanidin-3-glucoside.
MACRONONE, A NOVEL DIEPOXYLIGNAN FROM BARK OF MAHKOTA DEWA (Phaleria macrocarpa (Scheff.) Boerl.) AND ITS ANTIOXIDANT ACTIVITY Susilawati Susilawati; Sabirin Matsjeh; Harno Dwi Pranowo; Chairil Anwar
Indonesian Journal of Chemistry Vol 12, No 1 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (655.052 KB) | DOI: 10.22146/ijc.21373

Abstract

Mahkota dewa (Phaleria macrocarpa (Scheff.) Boerl.) which is belong to family of Thymelaeaceae is one of Indonesian traditional medicines. Chemical constituent has been isolated from bark of mahkota dewa. Sample was extracted with methanol. Concentrated methanol extract was extracted by n-hexane, chloroform and ethyl acetate. A Compound that separated and purified by column chromatography from ethyl acetate extract is a red spherical crystal (m.p. 94-95 °C). Its spot gave yellow fluorescence at TLC plate (UV366) and has optical rotation of -9.3°(c. 2 mg/mL, methanol). Structure elucidation by UV, IR, 1H-NMR, 13C-NMR and NMR 2 dimension (HMQC, COSY, HMBC and DEPT-135) spectroscopy show that the compound gives a name macronone. Computational chemistry calculation using Hyperchem on the level of semiempirical method PM3 was confirmed the conformation of macronone. DPPH method shows that macronone has lower antioxidant activity compare to the ethyl acetate extract.
GREEN CHEMISTRY APPLICATION FOR THE SYNTHESIS OF (1)-N-4’-METHOXYBENZYL-1,10-PHENANTHROLINIUM BROMIDE Maulidan Firdaus; Jumina Jumina; Chairil Anwar
Indonesian Journal of Chemistry Vol 8, No 3 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (957.228 KB) | DOI: 10.22146/ijc.21611

Abstract

A simple, energy-efficient, and relatively quick synthetic procedure for the synthesis of (1)-N-4'-methoxybenzyl-1,10-phenanthrolinium bromide, based on green chemistry principles has been carried out. The synthesis was started by solvent-free reduction of p-anisaldehyde with NaBH4 to give 4-methoxybenzyl alcohol in 98% yield to be followed by solvent-free treatment of the resulted alcohol with PBr3 to yield 4-methoxybenzyl bromide (86%). Furthermore, the obtained bromide was reacted with 1,10-phenanthroline in acetone at reflux for 12 h to give the phenanthrolinium salt target in 68% yield.
CALCIUM ABSORPTION KINETIC ON INDONESIAN RICE Chatarina Wariyah; Mary Astuti; Supriyadi Supriyadi; Chairil Anwar
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (246.95 KB) | DOI: 10.22146/ijc.21630

Abstract

Calcium absorption kinetic from three varieties rice i.e. low-, medium-, and high amylose content were evaluated. Three calcium salt (calcium acetate, -lactate and - gluconate) were used as a fortifican. Each rice was soaked at the calcium salts at soaking temperatures of 80, 90 and 100 oC, for 30 min and the calcium content was analyzed periodically. Reaction rate constant was determined from slope of curve of the relation of soaking time and absorbed calcium. The activation energy was determined by Arrhenius equation. The research showed that rice calcium absorption follows the first-order kinetic and absorption rate tends to decrease with increasing temperature. Calcium absorptions were affected by calcium salt solubility. Calcium acetate was absorbed easier than calcium lactate and calcium lactate was absorbed easier than calcium gluconate, but the absorption rate constant of calcium acetate was lower than that of calcium lactate, and calcium lactate was lower than calcium gluconate. Based on amylose content of rice, the higher the amylose content, the lower calcium absorption rate. The activation anergy of the high amylose rice was higher than that of low amylose content.