Iqmal Tahir
Austrian-Indonesian Centre (AIC) for Computational Chemistry, Universitas Gadjah Mada, Sekip Utara Yogyakarta 55281

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HUBUNGAN KUANTITATIF STRUKTUR ELEKTRONIK DAN AKTIVITAS ANTITUMOR SENYAWA TURUNAN AMINO PIRIMIDO ISOKUINOLIN KUINON DENGAN PENDEKATAN REGRESI KOMPONEN UTAMA Saputra, Andrian; Wijaya, Karna; Tahir, Iqmal
CHEMISTRY PROGRESS Vol 6, No 1 (2013)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.6.1.2013.2066

Abstract

Tujuan penelitian ini yaitu menganalisis Hubungan Kuantitatif Struktur Aktivitas (HKSA) turunan amino pirimidoisokuinolin kuinon yang berkhasiat sebagai antitumor telah dilakukan dengan menggunakan pendekatan regresikomponen utama. Data aktivitas biologis yang digunakan pada penelitian ini merupakan aktivitas senyawamelawan sel tumor AGS (Human Gastric Adenocarcinoma Cell Line) dalam ukuran log IC 50 . Sebagai deskriptordigunakan muatan atom bersih bersih (q) pada kerangka struktur senyawa dari hasil optimasi geometrimenggunakan perhitungan mekanika kuantum semiempirik AM1. Analisis komponen utama dilakukan sebelum proses regresi untuk mendapatkan variabel laten yang merupakan hasil transformasi data deskriptor muatanatom bersih (q). Dengan pendekatan regresi komponen utama diperoleh keterkaitan erat antara log IC 50 dan q yang direpresentasikan dengan persamaan HKSA berikut :log IC 50 = 0,671 - 0,041.x 1 + 0,232.x 2 + 0,270.x 3 - 0,087.x 4 + 0,105.x 5dengan, n = 27, r = 0,762, SE = 0,362, F hitung /F tabel = 2,168.Quantitative Structure Activity Relationship (QSAR) analysis of amino-pyrimido-isoquinolin-quinone analoguesas antitumor compound has been done using principal component regression approaches. Biological activitydata that used in this research were the activity against tumor cell AGS (Human Gastric Adenocarcinoma CellLine) as log IC 50 values. Atomic net charges (q) in the skeleton of the compound have been selected asdescriptors and all data were resulted by geometry optimization using AM1 semiempirical quantum mechanicscalculations. Principle component analysis has been performed before regression process to produce latentvariables by transformation of the descriptors. Based on principle component regression approaches, there isa selected quantitative relationship between log IC 50 to the descriptors that was shown by QSAR equation below:log IC 50 = 0.671 – 0.041.x 1 + 0.232.x 2 + 0.270.x 3 – 0.087.x 4 + 0.105.x 5with, n = 27, r = 0.762, SE = 0.362, F calc. /F table = 2.168.
Karakterisasi dan Aplikasi Katalis Nikel-Molibdenum Teremban pada Zeolit Alam Aktif untuk Hidrorengkah Tir Batubara Sugianto, Dwi Julian; Wijaya, Karna; Tahir, Iqmal
Jurnal Natur Indonesia Vol 16, No 1 (2014)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (743.026 KB) | DOI: 10.31258/jnat.16.1.10-22

Abstract

Preparation and characterization of nickel-molybdenum catalysts supported on activated natural zeolite over hydrorackingof coal tar have been done. Modification of catalyst was included activation of zeolite by HCl 6N, wet impregnation of Ni-Mo metal and leaching the Ni-Mo from zeolite surfaces with EDTA solution.The parameters of catalyst have been determinedi.e acid site number, the ratio of Si/Al, crystallinity, content of Ni-Mo metal, specific surface area, total pore volume, and poreaverage diameter. The hydrocracking of coal tar was carried out at the optimum temperature (450°C) by flowing H2 gas (flowrate of 20 mL/min) on the coal tar with ratio of feed:catalyst was 10:1. The resulting liquid product was analyzed by GC/GCMS.The result showed that catalytic hydrocracking with ZAA catalyst had the highest conversion of liquid products,which were 40.51% (w/w) compared to Ni-Mo/ZAA catalyst gave 28.61% and Ni-Mo/ZAA(E) gaves 28.06% (w/w). Thehighest light fractions (67.63% (w/w)) produced by using Ni-Mo/ZAA catalyst and the highest medium fractions wereproduced over ZAA catalyst which was 36.61% (w/w) and the highest total conversion on the product with Ni-Mo/ZAA(E)catalyst produced was 50.05% (w/w). The product analyzed with GC-MS result on the 9th highest peak showed that thehydrocracking products resulted over Ni-Mo/ZAA mostly were phenol and its derivatives.
PENGGUNAAN METODE SEMIEMPIRIK PM3 UNTUK EVALUASI INTERAKSI ALLOPURINOL–ASAM METAKRILAT UNTUK SINTESIS POLIMER TERCETAK MOLEKUL Tahir, Iqmal; Ahmad, Mohd Noor; Arbain, Dahyar
CHEMISTRY PROGRESS Vol 5, No 1 (2012)
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35799/cp.5.1.2012.648

Abstract

Tahir dkk., 2012. Penggunaan Metode Semiempirik PM3 Untuk Evaluasi Interaksi Allopurinol–Asam MetakrilatUntuk Sintesis Polimer Tercetak Molekul. Polimer tercetak molekul untuk aplikasi sensor allopurinol berbasis Quartz Crystal Microbalance dapatdirancang dengan pemodelan molekul menggunakan metoda mekanika kuantum-semiempirik PM3. Kajianditentukan berdasarkan interaksi molekular antara allopurinol sebagai templat dan asam metakrilat sebagaimonomer fungsional, sehingga diperoleh rasio mol antara allopurinol dan asam metakrilat secara teoritik.Pemodelan molekul dilakukan dengan pendekatan perhitungan mekanika kuantum semi empirik PM3 padaperangkat lunak Hyperchem 8.0. Hasil penelitian menunjukkan interaksi yang terbentuk melibatkan interaksinon kovalen terutama ikatan hidrogen. Kestabilan struktur pre kompleks dari allopurinol – asam metakrilatpaling tinggi pada rasio mol 1:3 yang digunakan sebagai rekomendasi rasio mol untuk sintesis polimer tercetakallopurinol.Kata kunci : allopurinol, asam metakrilat, semiempirik PM3, polimer tercetak molekul, Quartz Crystal MicrobalanceTahir et al., 2012. Use of PM3 Semiempirical Method to Evaluate of Allopurinol-Methacrylic Acids Interactionfor Synthesis of Molecular Imprinted Polymer. Molecular imprinted polymer of allopurinol for sensing application based on Quartz Crystal Microbalance can bedesigned using molecular modeling applying quantum mechanics-PM3 semiempirical calculation. The study isperformed theoretically by evaluating of the molecular interaction between allopurinol as templat molecule andmethacrylic acids as functional monomer molecules. All of the calculation is run on PM3 semiempirical levelusing HyperChem Software. The result showed that the existences of interaction are formed by non covalentbinding especially hydrogen bonding. Structure stability of pre complex between allopurinol-methacrylic acid isrelatively optimum at ratio 1:3 and it can be used as the experimental mole ratio to synthesize of allopurinolimprinted polimer.Keywords : allopurinol, methacrylic acid, semiempirical PM3, molecular imprinted polymer, QuartzCrystal Microbalance