bluuebunny/crossref_metadata_2025_split huggingface dataset:
BIOSORPTION OF Cr(III) ION ON ALGAE <i>Eucheuma spinosum</i> BIOMASSA
Authors: Sudiarta I Wayan , Diantariani Ni Putu 
Published: January 2019

Studies on biosorption and desorption of Cr(III) on algae (Eucheuma spinosum) adsorbent have been carried out. These studies included determination of biosorbent acidity, optimum pH, contact time of biosorption, isoterm and biosorption capacity, and mechanisms of interaction between Cr(III) and algae (E. spinosum) biosorben. Mechanisms of interaction were evaluated by sequential desorption of Cr(III) on algae biosorben by using aquadest, 1 M HCl and 0.05 M Na2EDTA. The result showed that the total acidity of algae biosorbent was 4.15 ± 0.33 mmol/g, the optimum pH was 3, and the optimum contact time was 20 min. Biosorption capacity of algae (E. spinosum) toward chromium (III) was 57.33 mg/g. The highest desorption of Cr(III) achieved when 1 M HCl was used, i.e. 51,01%, wheareas desorptions using aquadest and 0.05 M Na2EDTA were relatively low, i.e. 2.07% and 2.38% respectively. This result indicates that the main interaction mechanism of Cr(III) on algae was electrostatic attraction. Keywords : Biosorption, Cr(III), Eucheuma Spinosum
FOUR-FACTOR RESPONSE SURFACE OPTIMIZATION OF THE ENZYMATIC SYNTHESIS OF WAX ESTER FROM PALM KERNEL OIL
Authors: Gunawan Erin Ryantin , Suhendra Dedy 
Published: January 2019

The synthesis of wax ester using refined, bleached and deodorized (RBD) palm kernel oil (PKO) and oley alcohol catalyzed by Lipozyme IM was carried out. Response surface methodology (RSM) based on a five-level, four-factor central composite rotatable design (CCRD) was used to evaluate the interactive effects of synthesis, of reaction time (5-20 h), temperature (20-50 oC), amount of enzyme (0.1-0.2 g) and substrate molar ratio (palm kernel oil to oleyl alcohol, 1:1-1:5) on the percentage yield of wax esters. The optimum condition conditions derived via RSM were reaction time 8.46 h, temperature 44.4 oC, amount of enzyme 0.182 g, substrate molar ratio 1 to 3.7. The actual experimental yield was 92.9 % under optimum condition, which good accordance to the maximum predicted value of 92.4 %. Keywords: response surface methodology, central composite rotatable design, palm kernel oil, lipozyme, alcoholysis, wax ester
DIPRENYLATED XANTHONE FROM THE STEM BARK OF KANDIS GAJAH (<i>Garcinia griffithii</i>)
Authors: Elfita Elfita , Supriyatna Supriyatna , Bahti Husen H. , Dachriyanus Dachriyanus 
Published: January 2019

A diprenylated xanthone, 1,5-dihydroxy-3-methoxy-4,7-diprenylxanthone (1) had been isolated the first time from the dichloromethane extract of the stem bark of Garcinia griffithii, together with 1,7-dihydroxyxanthone (2) and polyisoprenylated benzophenone, guttiferone I (3). The structure of these compounds were determined on the basis of spectroscopic data including UV, IR, 1H NMR, 13C NMR, HMQC, HMBC and COSY. Keywords: diprenylated xanthone, 1,5-dihydroxy-3-methoxy-4,7-diprenylxanthone, Garcinia griffithii
A NEW PRENYLATED FLAVANONE FROM THE ARIAL PART OF <i>Orthosiphon stamineus</i>
Authors: Hossain M. Amzad , Rahman Atiqur , Kang Sun Chul 
Published: January 2019

Phytochemical investigations on the chloroform extract of the arial part of Orthosiphon stamineus resulted in isolation of one new prenylated compound 5,7-dimethoxy-3,4′-dihydroxy-3′,8-di-C-prenylflavanone together with four known flavonoids compounds, sinensetin, eupatorin, 5,6,7,4¢-tetramethoxyflavone and 3-hydroxy-5,6,7,4¢-tetramethoxyflavone. The structures were deduced on basis of different analytical methods such as UV, IR, 1H-NMR, 13C-NMR, DEPT, COSY, HMBQ and GC-MS. The prenylated compound is reported for the first time from this plant. Keywords: Orthosiphon stamineus, prenylated flavanone, flavonoids
THE USE OF CHLOROSULFONIC ACID ON SULFONATION OF cPTFE FILM GRAFTED STYRENE FOR PROTON EXCHANGE MEMBRANE
Authors: Yohan Yohan 
Published: January 2019

Sulfonation of g-ray iradiated and styrene-grafted crosslinked polytetrafluoro ethylene film (cPTFE-g-S film) have been done. The aim of the research was to make hydrophyl membrane as proton exchange membrane fuel cell. Sulfonation was prepared by using chlorosulfonic acid in chloroethane under various conditions. The impact of the percentage of grafting, the concentration of chlorosulfonic acid, the reaction time,and the reaction temperature on the properties of sulfonated film were examined. The results show that sulfonation of surface-grafted films was incomplete at room temperature. Increasing concentration of chlorosulfonic acid and reaction temperature accelerate the reaction but they also favor side reactions. These lead to the decrease of the ion-exchange capacity, water uptake, and proton conductivity but the increase of the resistance to oxidation in a perhydrol solution. The resulted cPTFE-g-SS membraneis stabile in a H2O2 30% solution for 20 h. Keywords: Chorosulfonic acid, sulfonation, PTFE film, proton excange membrane.
QM AND AB INITIO INVESTIGATION ON THE HYDROGEN BONDING, NMR CHEMICAL SHIFTS AND SOLVENT EFFECTS ON THE DPPE
Authors: Monajjemi M. , Nouri A. , Monajemi H. 
Published: January 2019

The hydrogen bonding effects that were produced from interaction of membrane lipid dipalmitoylphosphatidyl-ethanolamine (DPPE) with 1-5 water molecules, has been theoretically investigated through the quantum mechanical calculations at the Hartree-Fock level of theory and the 3-21G, 6-31G and 6-31G* basis sets with the computational package of Gaussian 98. According to the obtained results of the structural optimization of the isolated DPPE in the gas phase, we can see the evidences of interactions in the head group of this macromolecule (from the molecular point of view we have a proton transfer from the ammonium group to the phosphate oxygen of zwitterionic form. As we know that the hydrogen bonding of DPPE with water molecules which have surrounded its head group plays an important role in the permeability of DPPE. So, in order to understand the microscopic physico-chemical nature of this subject we have analyzed bond and torsion angles of DPPE before and after added water molecules. In this paper we have theoretically studied the complexes DPPE with water molecules which have surrounded its head group. As mentioned before, this theoretically study has been done through Hartree-Fock level of theory by using simple basis sets. Theoretical data shows that the interaction of head group of DPPE with water molecules causes some changes in the geometry of DPPE which were explained by the contribution of zwitterionic form of DPPE macromolecule, and finally hydrated DPPE becomes stable complex. Comparison between theoretical and experimental geometry data of DPPE macromolecule shows that the calculation at the HF/3-21 level of theory produces results which they are in better agreement with the experimental data. Moreover the hydrogen bonding effects on the NMR shielding tensor of selected atoms in the hydrated complexes of DPPE were reported. The ";Gauge Including Atomic Orbitals"; (GIAO) approaches within the SCF-Hartree-Fock approximation have been used in order to investigate the influence of hydrogen bonding of DPPE-water complex on the shielding tensors. Finally, the solvent affects on the stability of DPPE macromolecule, dipole moment and atomic charge of some selected atoms of DPPE molecule was discussed using Onsager model and Merz-Singh-Kolman schema. Keywords : Gauge Including Atomic Orbital, DPPE, hydrogen bonding, solvation, quantum mechanics, ab initio
THE PREPARATION OF AN IODATE SELECTIVE ELECTRODE USING SILVER IODATE AS THE ACTIVE AGENT IN A CHITOSAN SUPPORT
Authors: Mulyasuryani Ani , Fardiyah Qonitah , Sugiri Rizki 
Published: January 2019

The iodate-selective electrode based on the principle of precipitation reaction could be made by coating the platinum wire with silver iodate (AgIO3). In this research was carried out optimization the iodate-selective electrode using chitosan membrane as an AgIO3 support. The AgIO3 were added in the 2 mL 1% chitosan solution, is 0.5 to 2.5 % (w/v). The thickness of the membrane used is 6 to 12 µm. The electrode cell potential is measured against Ag/AgCl electrode as a reference electrode. The optimum electrode performance was at 2.0 % of AgIO3 with thickness a membrane of 10 µm. The iodate-selective electrode has a Nernstian factor is 52.96 mV/decade and a response time of 10 seconds. The concentration range was determined from 10-3 M to 10-1 M and the detection limit is 1.12 x 10-5 M. Keywords: Ion Selective Electrode, Iodate, Chitosan Membrane
THE EFFECT OF IRRADIATION DOSE AND AMMONIA CONCENTRATION ON THE APPLICATION OF ELECTRON BEAM FOR TREATMENT GASES POLLUTION OF SO<sub>2</sub>AND NO<sub>X</sub>
Authors: Erizal Erizal 
Published: January 2019

The application of electron beam for treatment gases pollution of SO2 and NOx has been studied. The simulated SO2 and NOx gases stream produced from diesel fuel burning boiler were flown into electron beam chamber. Irradiation was conducted using 1000 keV electron beam machine at the dose up to 8.8 kGy, while water vapour and the ammonia gas with variation concentration flew into the system during irradiation. The concentrations of the gases change were observed during processes. After evaluation, it was found that by increasing irradiation dose, the concentration of SO2 and NOx gases removal increases. The efficiency of gases removal may reach 98 % for SO2 and 88 % for NOX at a dose of 8.8 kGy. By increasing ammonia concentration, the efficiency gas removal increases. Besides, by-products from the irradiation yield were sulfate and nitrate salt compound which are possible to be used as a fertilizer. Keywords: radiation, electron beam, gas pollution, SO2, NOx, ammonia
ESTIMATION OF SEDIMENT ACCUMULATION RATE IN JAKARTA BAY USING NATURAL RADIONUCLIDE UNSUPPORTED <sup>210</sup>Pb
Authors: Lubis Ali Arman , Aliyanta Barokah , Menry Yulizon 
Published: January 2019

The investigation of sediment accumulation rate has been carried out in Jakarta Bay. The aim of this study is to estimate the accumulation rate of sediment using natural radionuclide 210Pb as a tracer, through the profile of unsupported 210Pb. Sediment cores of 40 cm and 30 cm length were collected using gravity core from 2 locations (TJ22 and TJ17A) in Jakarta Bay. Samples were sliced at 2 cm length, prepared and analyzed using PIPS detector Alpha Spectrometer. The result shows that in TJ22 consist of 3 layers; LS1 in the depth of (0-2) cm as a mixing layer, LS2 (2-16) and LS3 (16-26) cm and TJ17A has 3 layers; LS1 in the depth of (0-6) cm, LS2 (6-18) cm and LS3 (18-24) cm. Accumulation rate of sediment of LS2 and LS3 in TJ22 are 0.583 cm/y and 0.074 cm/y and in TJ17A are 0,852 cm/y and 0.115 cm/y, respectively. The accumulation rate of sediment since 30 years ago is higher than previous period. Keywords: Natural radionuclide, 210Pb, sediment, accumulation rate.
POTENCY OF MUNG BEAN SPROUT AS ENZYME SOURCE (α-AMILASE)
Authors: Suarni Suarni , Patong Rauf 
Published: January 2019

Mung bean sprouts contain enzyme of α-amylase. A research on the effect of the sprout age and sprout varieties to the α-amylase activity and the protein level has been carried out in Laboratorium Bioproses BB Pascapanen Bogor using Full Factorial Random Design with two factorials (1) sprout age; 1, 2, 3, 4, and 5 days as well as (2) varieties of mung bean; Kenari, Bhakti and Parkit. Parameters observed were water and protein content of sprout, pH, activities of α-amylase, and dissolved protein in the enzyme extract. Results showed that the optimum temperature of α-amylase was 30 ºC, the highest protein level of sprout and the highest activity of α-amylase were given by the sprout of Bhakti at the age of three days. The water content in sprout was 65.23%, the protein level was 12.93 %, the dissolved protein in the enzyme extract was 2.88743 mg/mL, pH was 5.45, and the activity of enzyme was 4.09 Unit/mL. The potency of enzyme found in mung bean can be utilized in industries processing materials having high starch content, such as maize flour. Keywords; sprout of mung bean, activity of α-amylase, protein
CYCLOPENTYL TRISILANOL SILSESQUIOXANES – MODIFIED NATURAL RUBBER (CpSSQ(OH)<sub>3</sub>– ENR-50) NANOCOMPOSITE IN THE PRESENCE OF TIN (II) CHLORIDE DIHYDRATE
Authors: Rosniza H. , Bakar M. A. , Hamid S. Abdul , Ismail J. 
Published: January 2019

A nanocomposite comprising cyclopentyl trisilanol silsesquioxanes (CpSSQ(OH)3) and 50% epoxidized natural rubber (ENR-50) was prepared at reflux temperature with Tin (II) chloride dihydrate (SnCl2.2H2O) as catalyst. SnCl2.2H2O was found to be an affective catalyst to promote ring opening in ENR-50 and tailored it to CpSSQ(OH)3 via chemical reaction. The generation of carbonyl functional groups arising from epoxide ring opening can be clearly seen in FTIR spectra. 1H and 29Si NMR analyses further proved that the incorporation of CpSSQ(OH)3 in ENR-50 occured. TGA studies showed a degradation temperature with 10% weight decreased and DSC thermogram indicates a single Tg. Single peak in XRD diffractogram at 2-Theta angle further confirmed the surface modification. Keywords: silsesquioxanes, ENR-50, oxirane ring opening, hybrid
KINETIC TRANSFORMATION OF SPINEL TYPE LiMnLiMn<sub>2</sub>O<sub>4</sub> INTO TUNNEL TYPE MnO<sub>2</sub>
Authors: Walanda Daud K 
Published: January 2019

Lithiated phase LiMn2O4 is a potential cathode material for high-energy batteries because it can be used in conjunction with suitable carbon anode materials to produce so-called lithium ion cells. The kinetic transformation of LiMn2O4 into manganese dioxide (MnO2) in sulphuric acid has been studied. It is assumed that the conversion of LiMn2O4 into R-MnO2 is a first order autocatalytic reaction. The transformation actually proceeds through the spinel l-MnO2 as an intermediate species which is then converted into gamma phase of manganese dioxide. In this reaction LiMn2O4 whose structure spinel type, which is packing between tetrahedral coordination and octahedral coordination, is converted to form octahedral tunnel structure of manganese dioxide, which is probably regarded as a reconstructive octahedral-coordination transformation. Therefore, it is a desire to investigate the transformation of manganese oxides in solid state chemistry by analysing XRD powder patterns. Due to the reactions involving solids, concentrations of reactant and product are approached with the expression of peak areas. Keywords: high-energy battery, lithium ion cells, kinetic transformation
THE USE OF TIO<sub>2</sub>-ZEOLIT AS A CATALYST ON THE DEGRADATION PROCESS OF ERIONIL RED DYE
Authors: Sumartono Agustin , Andayani Winarti 
Published: January 2019

Degradation of erionil red dye using photo catalytic processes with TiO2-zeolit as a catalyst was carried out. Degradation of the dye was observed in 10 L volume, and erionil red dye was used as a model of organic pollutant. The parameters examinated were intensity of the spectrum, the decrease of pH, percentage of degradation, and the efectifity TiO2-zeolit as a catalyst. The use of UV lamp and TiO2-zeolit as a catalyst showed a good results because the dye could be degraded. This could be seen from the decreasing of the intensity of the spectrum 24 h after illumination. The pH of erionil red increased from around 4 into 5.5 which is still acidic. Effectivity of TiO2 composit as a catalyst could be used only two times. The compound resulted from degradation that could be detected using HPLC was oxalic acid. Keywords: dye, erionil red, photocatalytic, TiO2
STRUCTURE MODIFICATION OF ANDROGRAPHOLIDE TO IMPROVE ITS POTENCY AS ANTICANCER
Authors: Poerwono Hadi , Hattori Yoshiyuki , Kubo Hajime , Higashiyama Kimio 
Published: January 2019

Andrographolide, a diterpenoid lactone isolated from the herb of Andrographis paniculata and known to possess antitumor activity in breast cancer models was subjected to semisynthesis leading to the preparation of a number of derivatives. After protection of the two hydroxyl groups present at C-3 and C-19 to give 3,19-isopropylidene and 3,19-benzylidene andrographolides, the remaining hydroxyl group at C-14 of andrographolide was treated with acid anhydride or acid chloride under base condition. Unfortunately, the reactions gave only 14-dehydroandrographolide as well as unidentified diacyl compounds in replace of the target molecule 14-O-acyl andrographolide. An alternative procedure using neat acetic anhydride under reflux gave the acetyl derivatives. The resulted compounds exhibited cytotoxic activity against MCF-7 breast cancer cells with better growth inhibition than the parent compound andrographolide. Keywords: andrographolide, acylation, anticancer, cytotoxic, breast cancer cells.
Zn-Al LAYERED DOUBLE HYDROXIDE AS HOST MATERIAL FOR SUNSCREEN COMPOUND OF p-AMINOBENZOIC ACID
Authors: Roto Roto , Tahir Iqmal , Mustofa Mustofa 
Published: January 2019

Zn-Al layered double hydroxide can be used as host material for UV active compound p-aminobenzoic acid (PABA), which is having capability to block UV light of sunlight. The formation of Zn-Al-PABA was best developed in which the nucleation process was done at room temperature and followed by hydrothermal treatment at 100 oC. To make a better product, the molar ratio of Zn to Al to PABA was adjusted to 3:1:1. From the elemental analysis and the content of PABA, it was observed that the product has structural formula of Zn0,745Al0.254(OH)1.650(PABA)0.349. 0.684H2O. The particle size of the powder as estimated using SEM was in the range 100-200 nm. FTIR and XRD proved that the p-amino benzoate ion occupied the interlayer space. This material is expected to have high sun protection factor (SPF). Keywords: layered double hydroxide, sunscreen, p-amino benzoic acid, nanoparticle
STUDY ON SENSITIZATION OF FULVIC ACID ON PHOTOREDUCTION OF Cr(VI) TO Cr(III) BY TiO<sub>2</sub> PHOTOCATALYST
Authors: Santoso Uripto Trisno , Mustikasaria Kamilia , Santosa Sri Juari , Siswanta Dwi 
Published: January 2019

Sensitization of fulvic acid (FA) on photoreduction of Cr(VI) to Cr(III) by TiO2 photocatalyst has been studied. Parameters influencing the sensitization, i.e., pH of medium, as well as FA concentrations, TiO2 concentrations and initial Cr(VI) concentrations were critically evaluated. Extraction of FA from peat soil sampled in Gambut, South Kalimantan, Indonesia, was performed using Amberlite XAD-7 resin. The FA extract then was purified by cation exchange method using Amberlite IRA-120 resin. The TiO2 produced by Merck was used as semiconducting photocatalyst and two 30-W UV lamps (Philips® model TUV) were used as photon source. The results showed that presence of FA on TiO2 suspensions could sensitize the photoreduction of Cr(VI), enhancing of the amount of reduced Cr(VI) more significantly than the sensitization by humic acid. The effectiveness of this sensitization increased with increasing initial concentrations of FA, TiO2, or Cr(VI) until certain concentration, but no further improvement can be observed in excess FA, TiO2, or Cr(VI) concentrations. On the contrary, the effectiveness of this sensitization decreased with increasing of the medium pH. Keywords: sensitization, fulvic acid, Cr(VI), photoreduction, TiO2.
THE PREFERENTIAL STRUCTURE OF Co<sup>2+</sup> SOLVATION IN AQUEOUS AMMONIA SOLUTION DETERMINING BY MONTE CARLO SIMULATION
Authors: Kusumawardani Cahyorini , Purtadi Sukisman , Partana Crys Fajar , Pranowo Harno Dwi , Mudasir Mudasir 
Published: January 2019

A Monte Carlo simulation was performed for Co2+ in 18.6 % aqueous ammonia solution at a temperature of 293.16 K, using ab initio pair potentials and three-body potentials for Co-H2O-H2O, Co-NH3-NH3 and Co-H2O-NH3 interactions. The first solvation shell consists average of 2.9 water and 3.2 ammonia molecules, and the second shell of 10.4 water and 11.2 ammonia molecules. The structure of the solvated ion is discussed in terms of radial distribution functions, angular distributions and coordination number. Keywords: Molecular simulation, Monte Carlo simulation, solvation, ab initio
SYNERGISTIC EXTRACTION OF COBALT(II) WITH MIXTURE OF ACYL-PYRAZOLON AND CROWN-ETHER IN STRONSIUM(II) ENVIRONMENT
Authors: Rusdiarso Bambang 
Published: January 2019

Synergistic extraction of cobalt(II) with mixture of acyl-pyrazolon (HL) and crown-ether (E) in the Sr(NO3)2 environment has been studied. In this research, HPMBP (phenyl-1-methyl-3-benzoil-4-pyrazolon-5) was used, with three different kinds of crown-ether, i.e. (benzo-15-crown-5), DB18C6 (dibenzo-18-crown-6) and DB24C8 (dibenzo-24-crown-8), in chloroform. In the bulk environment of stronsium, a cobalt coextraction and stronsium occured with species ESrNO3+,Co(PMBP)3-, and E = B15C5, while Co(PMBP)2E and ESr,Co(PMBP3)2, with E = DB18C6. There was no coextraction when using crown-ether DB24C8, with the extracted species Co(PMBP)2E. Values of extraction constant presented in log Kex were -6.08 (B15C5), - 4.51, -12.55 (DB18C6), and - 4.57 (DB24C8), respectively. Keywords: synergistic, cobalt (II), strontium (II), coextraction.
SYNTHESIS AND CONFORMATION OF p-(AMINO)BUTOXYCALIX[4]ARENE
Authors: Firdaus Firdaus , Jumina Jumina , Sastrohamidjojo Hardjono 
Published: January 2019

Derivatization of 5,11,17,23-tetra-t-butyl-25,26,27,28-tetrahydroxycalix[4]-arene to 5,11,17,23-tetra-amino-25,26,27,28-tetrabutoxycalix[4]arene compound via etherification, ipso nitration, and reduction reactions, respectively has been conducted. The etherification reaction was carried out by refluxed the mixture of 5,11,17,23-tetra-t-butyl-25,26,27,28-tetrahydroxy-calix[4]arene, 1-bromobutane, NaI, and NaH in solvent mixture of THF-DMF (10:1 v/v) and nitrogen atmosphere for 4 hours to resulted 5,11,17,23-tetra-t-butyl-25,26,27,28-tetrabutoxycalix[4]-arene 84% in yield; ipso nitration reaction was carried out by stirred the mixture of 5,11,17,23-tetra-t-butyl-25,26,27,28-tetrabutoxycalix[4]arene and HNO3 100% in solvent mixture of dichloromethane-acetic acid glacial (1:1 v/v) for 2 hours and than refluxed for 1 hour to resulted 5,11,17,23-tetra-nitro-25,26,27,28-tetra-butoxycalix[4]arene 50% in yield; and reduction reaction was carried out by refluxed the mixture of 5,11,17,23-tetra-nitro-25,26,27,28-tetrabutoxycalix[4]arene and SnCl2/HCl reductor in ethanol solvent for 6 hours to resulted 5,11,17,23-tetra-amino-25,26,27,28-tetrabutoxycalix[4]arene 67% in yield. In the etherification reaction, the conformation of calix[4]arene compound was converted from cone to partial cone; but in the followed reactions, i.e. nitration and reduction reactions, the conformation of calix[4]arene compounds were remain in partial cone. Keywords: aminobutoxycalixarene, conformation, etherification, ipso nitration, reduction
NUCHLEOPHILIC SUBSTITUTION REACTION OF CYANIDE AND METHOXYDE IONS TO QUATERNARY MANNICH BASE FROM VANILLIN
Authors: Purwono Bambang , Daruningsih Estiana E.P 
Published: January 2019

The nucleophilic substitution reaction to quaternary Mannich base from vanillin has been investigated. Mannich reaction to vanillin was carried out by refluxing mixture of vanillin, formaldehyde and dimethyl amine. Quaternary ammonium halide salt was obtained from reaction of Mannich vanillin base with methyl iodide in THF solvents and yielded 93.28%. Nucleophilic substituion to the halide salts with cyanide nucleophile produced 4-hidroxy-3-methoxy-5-(cyano)methylbenzaldehyde in 54.39% yield, with methoxyde ion obtained 4-hidroxy- 3-methoxy-5-(methoxy)-methyl-benzaldehide in 67.80% yield. The nucleophilic substitution reaction showed that substituen of trimethylamino quaternary Mannich base can act as a good leaving on nucleophilic reaction substitutions. Keywords: Mannich Reaction, Vanillin, nucleophilic substitution.