Pentyl 2-(1H-indole-2-carboxamido)benzoate (5) is obtained in good yield as stable crystals by reaction of pentyl 2-amino benzoate (6) with indole-2-carbonyl chloride acid (7) in the presence of pyridine. The crystal structure of 5 confirms the presence of intramolecular hydrogen bonding (N-H O) which produces a six-membered ring, and the molecules are linked together by intermolecular hydrogen forces (N-H O). | Synthesis characterization and crystal structure of pentyl 2- 1H-indole-2-carboxamido benzoate Current Chemistry Letters 8 2019 63 68 Contents lists available at GrowingScience Current Chemistry Letters homepage Synthesis characterization and crystal structure of pentyl 2- 1H-indole-2- carboxamido benzoate Kamal Sweidana Monther Khanfara Ala a Al-Shamaileha Mahmoud Sunjukb and Rajendra Joshic a Department of Chemistry The University of Jordan Amman 11942 Jordan b Department of Chemistry Hashemite University Zarqa 13115 Jordan c Department of Chemical Science and Engineering School of Engineering Kathmandu University Nepal CHRONICLE ABSTRACT Article history Pentyl 2- 1H-indole-2-carboxamido benzoate 5 is obtained in good yield as stable crystals Received November 21 2018 by reaction of pentyl 2-amino benzoate 6 with indole-2-carbonyl chloride acid 7 in the Received in revised form presence of pyridine. The crystal structure of 5 confirms the presence of intramolecular November 21 2018 hydrogen bonding N-H O which produces a six-membered ring and the molecules are Accepted December 28 2018 linked together by intermolecular hydrogen forces N-H O . Available online December 28 2018 Keywords Carboxamide Indole Nucleophilic acyl substitution NMR MS data 2019 by the authors licensee Growing Science Canada. X-ray structure determination 1. Introduction Heterocyclic moieties are present in a wide variety of drugs due to their remarkable medicinal properties. Various derivatives of indole-2-carboxamide were synthesized and shown to exhibit different biological activities examples include compounds 1 acting against Mycobacterium tuberculosis Mtb 2 an antihyperlipedimic agent 3 a PI3Kα EGFR inhibitor and 4 an anticancer agent Fig. 1 .1-4 Amide bond formation utilizes either the reaction of carboxylic acid derivatives with amines in the presence of bases such as triethylamine or pyridine. These reactions are called indirect Alternatively .