American Journal of Organic Chemistry 2017, 7(1): 13-18 DOI: 10.5923/j.ajoc.20170701.03 New Triterpenoid from the Roots of Calotropis gigantea (L) Dryand (Asclepiadaceae) Iman Omer 1,2 , Ibrahim Abdurrahman 1,3 ‚ Yang Cai-Xia 1,* 1 College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou City, China 2 School of Health Science, Ahfad Uuniversity for Women, Omdurman, Sudan 3 Unit of Basic Science, Faculty of Agriculture, University of Zalingei, Zalingei, Sudan Abstract Seven triterpenoid derivatives were isolated from the roots of Calotropis gigantea (L) Dryand, a Chinese traditional medicinal plant. Their structures were established on the basis of their spectroscopic data and comparison with those in the literature. A new triterpenoid acetate derivative, compound 7, Calotropisis, was isolated and characterized by spectral methods. Keywords Calotropis gigantean, Acelepiadaceae, Triterpenoid derivatives 1. Introduction Calotropis gigantea (L) Dryand (Asclepiadaceae) is mostly distributed in tropical and semitropical areas, mainly in Southwest China and South China in the wild [1-3]. It has been used in traditional medicine for the treatment of various ailments like parasitic diseases, digestive bloating from gas, cough, leprosy, and asthma by the people of the Li nationality, who are indigenous to Hainan island in China. Additionally, the plant is also used as a source of methane through anaerobic fermentation for bio fuel production [4]. This plant has been thoroughly explored for its many medicinal properties [5-7]. The chemistry of C. gigantea has been extensively investigated, leading to the isolation, of pregnanes [8, 9], flavonoids [10], a nonprotein amino acid [11], cardenolides [12-14] and terpenes [15-19]. In the present paper, we describe the isolation and structural elucidation of new triterpenoid acetates identified as calotropisis. 2. Experimental 2.1. Instrumentation and Materials NMR Spectra were recorded on a Bruker-DRX-400-NMR, ( 1 H at 400Hz and 13 C at 100Hz) spectrometer (Bruker Biospin Inc., Germany) and chemical shift values are given on a δ (ppm) scale with TMS as internal standard. 2D-NMR experiment was performed using standard Bruker * Corresponding author: yangcx@nwnu.edu.cn (Yang Cai-Xia) Published online at http://journal.sapub.org/ajoc Copyright © 2017 Scientific & Academic Publishing. All Rights Reserved micro-program (XWIN-NMR version 2.6 software. HR-EI-MS experiments were performed using a micro-mass–QTOF micro instrument, with an electro-spray ionization source (eV= 70 V, 80°C) (Waters Ltd., England). Column chromatography was carried out on silica gel (Merck kiesel gel 300-400 mesh, Qingdao Haiyang Chemical Group Company, China), TLCs were carried out on GF 254 silica gel plates (Merck, Qingdao Haiyang Chemical Group Company, China). All solvents were of commercial grade and used after further purification by simple distillation. 2.2. Plant Material The Roots of C. gigantea were collected in August 2016 from Hunan province, south of China, and the plant was authenticated by prof. Chen Quan Yuan at the college of biology, Northwest Normal University, China, where a voucher specimen (No. 20141016) has been deposited in the herbarium of author’s laboratory. 2.3. Extraction and Isolation The roots of the C. gigantean (Linn.) were air-dried for four weeks and ground into a powder. The root (15Kg) was sequentially extracted three times with 17 liters of ethanol at room temperature for 7 days each. Then, the extracts were filtered through cotton and concentrated with a rotary evaporator at 45°C for removal of the organic solvent and dried. A total of 3kg of ethanolic extracts were dissolved in 5L hot distilled water and then prepared by successive partition with petroleum ether (PE) (40-60°C) (fraction I), chloroform (fraction II), ethyl acetate (fraction III) and methanol (fraction IV). Each partition step was repeated three times to ensure complete extraction in each case.