Short Communication

Crystal Structure and Disorder in Benzothiophene Derivative

Mohamed ziaulla*

Department of Chemistry, Impact College of Engineering and Applied Sciences, India

Submission: August 10, 2018; Published: August 24, 2018

*Corresponding author: Mohamed ziaulla, Department of Chemistry, Impact College of Engineering and Applied Sciences, Bangalore-92, India, Email id: mohamed.ziaulla@gmail.com

How to cite this article: Mohamed z. Crystal Structure and Disorder in Benzothiophene Derivative. Organic & Medicinal Chem IJ. 2018; 7(5): 555721. DOI: 10.19080/OMCIJ.2018.07.555721

Keywords:2-Amino-6-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile (1) and 2-Amino-7-oxo-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile (2) with various N-H…O, N-H…O and N-H…S interactions

Introduction

Benzothiophenes are important heterocycles either as biological active molecules or as luminescent components used in organic materials [1-3]. One of the most important drugs based on the benzothiophene system is Raloxifene which was approved by the U.S. Food and Drug Administration for the prevention and treatment of osteoporosis in postmenopausal women [4-6]. Raloxifene is a representative of a class of compounds known as selective estrogen receptor modulators (SERMs) that exhibit estrogen agonist-like actions on bone tissues and serum lipids while displaying potent estrogen antagonist properties in the breast and uterus. Recently, 3-oxygenated benzothiophene has been reported to display a substantial (10-fold) increase in estrogen antagonist potency relative to raloxifene [7-11]. We report herein the Crystal structure of 2-Amino-6-methyl-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile (1) and 2-Amino-7-oxo-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile(2)

X-Ray Analysis and Refinement

The X-ray diffraction data for the compound 1 was collected on a Bruker Smart CCD Area Detector System. Intensity data were collected up to a maximum of 29.2° for the compound in the –ф scan mode. The data were reduced using SAINTPLUS [12]. A total of 11284 reflections were collected, resulting in 2441 independent reflections of which the number of reflections satisfying I>2 σ(I) criteria were 1878. These were treated as observed. The structure was solved by direct methods using SHELXS97 [13] and difference Fourier synthesis using SHELXL97 [13]. The compound Z3 crystallizes in monoclinic space group P21/c. The fused benzothiophene ring system is substituted with amino, methyl and carbonitrile groups. The thiophene ring is essentially planar (r.m.s. deviation = 0.05Å). The carbon atoms C9 and C10 are disordered over two sites (C9A/C9B and C10A/C10B) with site occupancy factors 0.650(3) and 0.350(3) resulting in a major and a minor conformers (Figure 1).

X-Ray Analysis and Refinement

The X-ray diffraction data for the compound 2 was collected on a Bruker Smart CCD Area Detector System. Intensity data were collected up to a maximum of 27.0° for the compound in the –ф scan mode. The data were reduced using SAINTPLUS [12]. A total of 6202 reflections were collected, resulting in 2058 independent reflections of which the number of reflections satisfying I>2 σ(I) criteria were 1671. These were treated as observed. The structure was solved by direct methods using SHELXS97 [13] and difference Fourier synthesis using SHELXL97 [13]. The positions and anisotropic displacement parameters of all non-hydrogen atoms were included in the full-matrix least-square refinement using SHELXL97[13] (Figures 2 & 3) [14,15].

Acknowledgement

ZIA is thankful to Dr. Paul Mathulla, Chairman of governing council and Dr. Alice Abraham, President, Impact Group of Institutions for their constant support and encouragement.

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