DFT, Quantum Chemical Study and Biological Effects of a Heterocyclic Molecular Research Article Journal of Biotechnology & Bioresearch C CRIMSON PUBLISHERS Wings to the Research 1/5 Copyright © All rights are reserved by Z Tribak. Volume - 1 Issue - 4 Zineb Tribak 1 *, Mohammed Khalid Skalli 1 , Amal Haoudi 1 , Youssef Kandri Rodi 1 and Omar Senhaji 2 1 Laboratory of Applied Organic Chemistry, Faculty of Sciences and Technology, B.P. 2202, Sidi Mohamed Ben Abdellah University, Fez Morocco 2 Biomolecular and Macromolecular Chemistry Team, Faculty of Sciences B.P. 11201, Moulay Ismail University, Meknes Morocco *Corresponding author: Zineb Tribak, Laboratory of Applied Organic Chemistry, Faculty of Sciences and Technology, B.P. 2202, Sidi Mohamed Ben Abdellah University, Fez Morocco, Email: tribak.zineb@gmail.com, Tel: +212 659899497 Submission: January 10, 2019; Published: February 21, 2019 Introduction 5-Chloroisatin derivatives [1] are well known for their versatile therapeutic agents in medicine, exhibiting antimicrobial [2], anti- inflammatory [3], antioxidant [4,5], anticancer [6], antibiotic [7], anti-HIV [8], anticonvulsant [9], antitubercular [10] activities and relaxant effects [11]. Density functional theory (DFT) studies have evolved to a powerful and very reliable tool, being routinely used for the determination of various molecular properties [11]. In view of these observations, the aim of the present investigation was to design 5-chloro-1-(prop-2-yn-1-yl)indoline-2,3-dione (TZ P ) in the search for high expected antibacterial interest against gram positive bacteria Bacillus subtilis, Staphylococcus aureus and Gram-negative bacteria Escherichia coli. Then, a description of the molecular geometry, frontier molecular orbital (HOMO and LUMO), global and local reactivity descriptors and MEP features of the title compound using density functional theory using (DFT/B3LYP) method with the 6-31G (d, p) basis set [12]. Experimental General All melting points are uncorrected. 1 H-NMR (300MHz) and 13 C-NMR (75MHz) spectra were obtained on Bruker equipment using CDCl 3 as solvent. Chemical shifts are given in ppm with TMS as an internal reference. J values are given in Hertz. Signals are abbreviated as singlet, s; doublet, d; double-doubles, dd; triplet, t; multiplet, m. Chromatography was performed with silica (mesh) and reactions were monitored by thin layer chromatography (TLC) with silica plates coated with silica gel. General procedure 5-chloro-1H-indole-2,3-dione (0,4g, 2,20mmol) was dissolved in 15mL of N, N-di methyl formamide (DMF) and 0,5g (3,3mmol) of K 2 CO 3 , BTBA (0,1g, 0,3mmol) and 1.2 equivalent of propargyl bromide were added, and the mixture was stirred for 48 hours at room temperature. The reaction progress was monitored by TLC. The solvent was removed in vacuo and co-evaporated with methylene Chloride (CH 2 Cl 2 ) several times, to remove the remaining traces of DMF. This yielded the product as a red to orange solid. No purification was necessary. Compound TZ P : 5-chloro-1-(prop-2-yn-1-yl)indoline-2, 3-dione: yield: 88% ; M.P: 166-170 °C; R f = 0.78 ; 1 H NMR (CDCl 3 ) δppm 7.57-7.62 (m, 2H, H Ar ); 7.12 (d, H, H Ar , 3 J H-H =6Hz); 4.54 (s, 2H, CH 2 ); 2.34 (t, H, 4 J H-H =3Hz); 13 C NMR (CDCl 3 ) δppm: 181.55 (C=O); 156.60 (N-C=O); 147.87, 130.07, 118.50 (CQ); 137.80, 125.24, 112.75 (CH Ar ) ;73.72 (C≡C) ;71.21 (CH); 29.59 (CH 2 ) Antibacterial activity Antibacterial screening of compound 5-chloro-1-(prop-2-yn- 1-yl) indoline-2,3-dione (TZ P ) was determined by a disc diffusion method, against two bacteria Gram - : Pseudomonas aeruginosa, Escherichia coli, and two others Gram + : Bacillus cereus and Staphylococcus aureus using LB medium. Antibacterial activity was carried out according to the method reported by [13] by the determinations of Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) [14]. The diameter of the inhibition zone around each disc was measured (Table 1). Abstract In this paper, the title compound 5-chloro-1-(prop-2-yn-1-yl)indoline-2,3-dione (TZ P ) has been prepared by N-alkylation method with a good yield. The structure of the compound was further confirmed from the 1H NMR and 13C NMR Spectral data and It has been screened for its antibacterial activity. The results revealed that the compound exhibited good to moderate antibacterial activity. Through computational study based on density functional theory (DFT/B3LYP) using basis set 6-31G (d,p) a number of chemical Quantum descriptors were computed to predict the reactivity and the reactive sites on the molecules. The molecular geometry and the electronic properties such as frontier molecular orbital were investigated to get a better insight of the molecular properties. The Molecular electrostatic potential (MEP) for the compound was determined to check their electrophilic or nucleophilic reactivity. Keywords: 5-Chlorosatin; N-alkylation; Antibacterial effects; DFT; HOMO; LUMO; MEP