Djulia Onggo

Docking Interaction of Protein Tyrosine Phosphatase and Complex Chromium(III) Nicotinate Compounds

Docking simulation is important in the process of drug design, mainly used for the prediction of interactions receptor(protein)–substrate. This study aims to understand the interaction between Chromium(III) nicotinate [Cr(O-nic)2(OH ) (H2O)3] and [Cr(N-nic)2(OH )(H2O)3] with the position of trans and cis as a substrate with receptors Protein Tyrosine Phosphatase(PTP). The chromium(III) nicotinic complexes an antidiabetic supplement that have been demonstrated in vitro, to determine the role of chromium(III) nicotinic as a supplement antidiabetic learned through the docking mechanism. The optimization of the complex structure of chromium(III) nicotinic using Gaussian 09, the docking process is performed using Autodock Vina. The docking results showed that trans[Cr(O-nic)2(OH )(H2O)3] position interact with Leu13, Gly14, Cys17, Arg18, Trp49 and Asn50 with the interaction energy is -6.5 kcal/mol. As for the structure model cis[Cr(O-nic)2(OH )(H2O)3] have 6.1 kcal/mol interaction energy and the amino acid Ile16, Trp49, Asn50, Arg53, Asp56 and Tyr131. The similar things at model of N-coordinated to Cr with trans[Cr(N-nic)2(OH )(H2O)3] position interact with amino acids Leu13, Ser47, Trp49, Asn50 and Tyr131 the interaction energy is -6.5 kcal/mol. The ONIOM calculation showed the bond between the complexes of chromium(III) nicotinic with PTP is hydrogen bonding. The best interactions with the receptor are the structure model trans[Cr(O-nic)2(OH )(H2O)3] with the lowest interaction energy interaction.

CRYSTAL STRUCTURE OF [Bis(DIMETHYLFORMAMIDE) Bis(2,2’-PYRIDYL)QUINOLINE)IRON(II)]Bis-(TETRAPHENYLBORATE)

The goal of this research is to obtain single crystal and structural information of iron(II) complex with 2,(2’pyridyl)quinoline(pq) ligands. The reaction of iron(II) salt with 2,(2’-pyridyl)quinoline ligand and sodium tetraphenylborate in the molar ratio of 1:3:2 in methanol-N,N-dimethylformamide(dmf) solution results in an iron(II) complex. The formula of the [Fe(pq)2(dmf)2](BPh4)2 complex has been obtained from the iron(II) and C, H, N contents. Single crystal of [Fe(pq)2(dmf)2](BPh4)2 suitable for X-ray investigation was obtained by evaporation of the complex solution in N,N-dimethylformamide at room temperature after 24 hours. This compound crystallizes in monoclinic system with C2/c space group, a = 27.950(4), b = 14.169(7), c = 17.717(9) A and β = 105.669(11)°. The structure consist of iron(II) is chelated by two pq ligands through the N atoms and two dmf molecules in a six-coordination environment. The charge of the [Fe(pq)2(dmf)2] cation is balanced by two tetraphenylborate (BPh4) anions.

Ferroelectric Properties of Ba2Bi4Ti5O18 Doped with Pb2+, Al3+, Ga3+, In3+, Ta5+ Aurivillius Phases

In recent years, bismuth layer structured ferroelectrics (BLSFs) have been given much attention because some materials, such as Ba2Bi4Ti5O18, are excellent candidate materials for nonvolatile ferroelectric random access memory (FRAM) applications. BLSFs are also better candidates because of their higher Curie points. Recently, we have carried out computer simulation in atomic scale in order to predict the energies associated with the accommodation of aliovalent and isovalent dopants (Pb2+, Al3+, Ga3+, In3+, Ta5+) in the Aurivillius structure of Ba2Bi4Ti5O18. In this work, the predicted stable phases were synthesized using solid state reactions and their products then were characterized using powder X‐ray diffraction method. The cell parameters were determined using Rietveld refinement in orthorhombic system with space group of B2cb. The cell parameters for Ba2Bi4Ti5O18 doped with Pb2+, Al3+, Ga3+, In3+, Ta5+ were a = 5.5006(6) b = 5.4990(5) c = 50.5440(7) A; a = 5.5012(4) b = 5.4986(8) c = 50.5449(7) A; a...