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Molecular Modeling of Debromolaurinterol Isolated from Sea hare (Aplysia kurodai) Using MOPAC Software

Janeth C. Tayone, Romeo M. Del Rosario


This study aimed to obtain a molecular model of a cytotoxic compound debromolaurinterol isolated by Tsukamoto  et al. (2005) from sea hare (Aplysia kurodai) using Molecular Orbital Package (MOPAC) software.  This semi-empirical approach was done by creating a Z-matrix of the molecule which was then converted to its MOPAC input data.  Optimization of these data had provided the specific bond distance , bond angle, dihedral angle of the most stable molecular geometry.   Furthermore, calculated energies like heat of formation (-6.75618 kcal/mol),  ionization energy (8.80571 eV), electronic energy (-17,174.16327 eV) and core-core repulsion energy (14,651.44307 eV) were generated. The interatomic distances between atoms of the molecule were also provided that may greatly influence the physical and chemical properties.  Finally,  MOPAC calculations generated visual models of the most stable molecular geometry in stick, ball and stick, wireframe and space fill configuration. This study therefore provided new information which is very important for chemistry educators as well as biosynthetic chemist in designing possible chemical reactions in order to synthesize product or its derivative that are experimentally difficult to conduct.  


Aplysia kurodai; molecular modeling; Molecular Orbital Package (MOPAC); z-matrix; theoretical calculations.

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