Studies On The Chemical Constituents Of Croton Crassifolius Geisel

Croton crassifolius Geisel (Euphorbiaceae) is known as "jiguxiang" in China,and distributed mainly in south and southwest China, Vietnam, Laos, and Thailand.The roots of C. crassifolius are used as a traditional medicine for the treatment ofstomachache, sore throat, rheumatismand cancer. Previous investigations have shownthat the genus Croton is a rich source of diterpenoids with clerodane skeleton, butthere are a few reports about the study of the plant C. crassifolius.In order to search for the bioactive constituents of C. crassifolius, the chemicalconstituents of C. crassifolius were investigated systematically. Twenty-fivecompounds were isolated from the EtOAc extract of the roots of C. crassifolius.Structures of the compounds were elucidated by spectroscopic methods and bysingle-crystal X-ray diffraction analysis. The structure of twenty-five compoundswere identified as Crassifolin A (JGX-1), Crassifolin B (JGX-2), Crassifolin C(JGX-3), Crassifolin D (JGX-4), Crassifolin E (JGX-5), Crassifolin F (JGX-6),Crassifolin G (JGX-7), spiro[furan-3(2H),1’(2’H)-naphthalene]-5’-carboxylic acid(JGX-8), Chettaphanin (JGX-9), Penduliflaworosin (JGX-10),1,4-methano-3-benzoxepin-2(1H)-one (JGX-11), Isoteucvin (JGX-12), Teucvin(JGX-13), Crassifolin H (JGX-14), Crassifolin I (JGX-15), Mallotucin D (JGX-16),Chettaphanin II (JGX-17), Cypenrenoic acid (JGX-18), Syringic acid (JGX-19),Lupol (JGX-20), Acetylaleuritolic acid (JGX-21), Aleuritolic acid (JGX-22),Epitaraxerol (JGX-23), β-Sitosterol (JGX-24), Stigmasterol (JGX-25). Among them,JGX-1~JGX-7, JGX-14, JGX-15were new compounds, and JGX-12, JGX-16,JGX-19, JGX-22were isolated from the plant for the first time.We also investigate the fingerprint of C. crassifolius for the first time. Themethod was carried out at40°C on a Zorbax SB-C18reserved-phase column (4.6×250mm,5μm) and a linear gradient elution of eluents A (Water-three trifluoroacetic acid,100:0.05, v/v) and B (CH3OH). The flow rate was1.0mL/min and detectionwavelength was set at220nm. As a result, the HPLC fingerprint chromatogram of C. crassifolius was established and10common peaks were found. Among them,8peakswere identified by comparing with the references isolated from this plant. In addition,a simple and rapid high performance liquid chromatography method with photodiodearray detection (HPLC-DAD) was developed to determine the content ofChettaphanin (JGX-9) in the plant.