Structural identification of the related substances in phloroglucinol injection by two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry / 药学学报

This study aimed to identify the related substances of phloroglucinol injection by two-dimensional liquid chromatography quadrupole time-of-flight mass spectrometry (2D-LC-Q-TOF/MS). The first-dimensional separation was carried out on an HSS T3 (250 mm × 4.6 mm, 5 μm) column by gradient elution using 1.36 g·L-1 potassium dihydrogen phosphate buffer solution (pH adjusted to 3.0 with diluted phosphoric acid) and acetonitrile as the mobile phases. The separated components were then trapped in switch valve tube lines respectively and delivered to the second-dimensional desalting gradient elution which was performed with a BDS C18 (100 mm × 4.6 mm, 2.4 μm) column using 0.1% formic acid and methanol as the mobile phases. After rapid desalting, electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry was used for determining the accurate masses and elemental compositions of the parents and their product ions for both phloroglucinol and its related substance. Structures of the related substances were then figured out by mass spectrometry elucidation, organic reaction mechanism analysis, and/or comparison with reference substances. Under the established analytical conditions, phloroglucinol and its related substances were adequately separated, 17 main related substances were detected and identified in the injection and its stressed samples for the first time. The identification results can provide reference for the quality control of phloroglucinol injection.

Identification of involatile chemical components from Moutai-flavored distiller’s grains / 中国药科大学学报

@#In order to study the involatile chemical components in Moutai-flavored distiller’s grains, the Moutai-flavored distiller’s grains were extracted with 75% ethanol, followed by extraction with petroleum ether, ethyl acetate, and n-butanol. Silica gel, ODS, sephadex LH-20, and preparative HPLC were used to separate and identify the petroleum ether and ethyl acetate layers.ESI-MS and NMR were used to identify the compounds, which were respectively identified as pentadecanoic acid (1), palmitic acid (2), trans-2-decenoic acid (3), n-nonyl octadecanoate (4), ethyl octadecanoate (5), ethyl linoleate (6), luric acid (7), 1, 3-dicaprylyl-2-linoleylglycerin (8), cyclic (phenylalanine-proline) (9), cyclo-(proline-leucine) (10), 3, 6-bis-(2-methylpropyl)-2,5-dione piperazine (11), 4-hydroxyphenethyl alcohol (12), 2,4-dihydroxybenzoic acid (13), stigmasterol (14), 2-furancarboxylic acid (15), valine (16), L-alanine acyl-L-proline (17), dihydroquercetin (18), 5, 7, 3'', 4''-tetrahydroxyflavonoids (19), quercetin (20), and naringenin (21). Compounds 1-21 were isolated from distiller’s grains for the first time.

Characterization and identification of chemical components in traditional Chinese medicine Psoraleae Fructus based on UHPLC-Q-TOF-MS / 中国中药杂志

This study was designed to comprehensively characterize and identify the chemical components in traditional Chinese medicine Psoraleae Fructus by establishing an ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS) method in combination with in-house library. The chromatographic separation conditions(stationary phase, column temperature, mobile phase, and elution gradient) and key MS monitoring parameters(capillary voltage, nozzle voltage, and fragmentor) were sequentially optimized via single-factor experiments. A BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) was finally adopted, with the mobile phase consisting of 0.1% formic acid in water(A) and acetonitrile(B) at the flow rate of 0.4 mL·min~(-1) and column temperature of 30 ℃. Auto MS/MS was utilized for data acquisition in both positive and negative ion modes. By comparison with reference compounds, analysis of the MS~2 fragments, in-house library retrieval and literature research, 83 compounds were identified or tentatively characterized from Psoraleae Fructus, including 58 flavonoids, 11 coumarins, 4 terpenoid phenols, and 10 others. Sixteen of them were identified by comparison with reference compounds, and ten compounds may have not been reported from Psoraleae Fructus. This study achieved a rapid qualitative analysis on the chemical components in Psoraleae Fructus, which provided useful reference for elucidating its material basis and promoting the quality control.

Chemical constituents of Scrophulariae Radix and their antitumor activities in vitro / 中国中药杂志

The present study investigated the chemical constituents of Scrophulariae Radix and their antitumor activities in vitro. The compounds in the ethyl acetate extract were separated and purified by conventional column chromatographies(such as silica gel, Sephadex LH-20, and ODS column) and semi-preparative high-performance liquid chromatography(HPLC), and their structures were identified by various spectral techniques such as nuclear magnetic resonance(NMR) and mass spectrometry(MS). Twenty-three compounds were isolated and identified as benzyl-β-D-(3',6'-di-O-acetyl) glucoside(1), 5-O-p-methoxybenzoyl kojic acid(2), 5-O-methoxybenzoyl kojic acid(3), 7-O-methylbenzoyl kojic acid(4), 5-O-benzoyl kojic acid(5), methyl ferulate ethyl ether(6), trans-ferulic acid(7), trans-isoferulic acid(8), trans-caffeic acid(9), trans-caffeic acid methyl ester(10), caffeic acid ethyl ester(11), trans-cinnamic acid(12), trans-p-methoxycinnamic acid(13), trans-p-hydroxycinnamic acid(14), trans-p-hydroxycinnamic acid methyl ester(15), 2-(3,4-dihydroxyphenethyl) alcohol(16),(p-hydroxyphenyl) propanoic acid(17), coniferaldehyde(18), sinapaldehyde(19), benzyl β-primeveroside(20), 5-(hydroxymethyl) furfural(21), furan-2-carboxylic acid(22), and decanedioic acid(23). Among them, compound 1 is a new benzyl glucoside, compounds 2-4 are new pyranone compounds, compound 5 is a new natural product of pyranone. The NMR data of compounds 5 and 6 are reported for the first time. Compounds 6 and 20 were isolated from the Scrophularia plant for the first time. Compounds 8, 11, 14, 16, 18, 19, 22, and 23 were isolated from this plant for the first time. The in vitro cytotoxic activities of these compounds against three tumor cell lines(HepG2, A549, and 4 T1) were evaluated. The results showed that compounds 10 and 15 showed cytotoxic activities against HepG2 cells with IC_(50) values of(19.46±0.48) μmol·L~(-1) and(46.10±1.21) μmol·L~(-1).

Structural identification of the related substances of lorazepam tablets by LC-MS / 中国药科大学学报

@#This study aimed to identify the related substances of lorazepam tablets by liquid chromatography mass spectrometry (LC-MS). To separate the related substances of lorazepam tablets, gradient elution was performed using acetonitrile and 0.1% acetic acid -20 mmol/L of ammonium acetate as mobile phase on Inert Sustain C18 (250 mm × 4.6 mm, 5 μm).The accurate mass and elemental composition of the parent ions and their product ions of related substances were determined by electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry (ESI-Q-TOF/MS).The structures of the related substances were identified by spectral analysis. Under the established analytical condition, lorazepam and its related substances were adequately separated, and 22 major related substances with content greater than 0.1% were detected and identified by hyphenated techniques in lorazepam tablets and their stressed samples.Among them, 5 were the impurities listed in the USP or EP, and the others were unknown related substances identified for the first time in this paper.The LC-MS technique can effectively separate and identify the related substances of lorazepam tablets, which provides some reference for quality control.

Establishment of national reference standard of tazobactam impurity A / 中国药科大学学报

@#To improve the standard of quality control of tazobactam and its preparations in China, national reference standard of tazobactam impurity A was developed. After tazobactam impurity A was synthesized, its structure was validated by infrared (IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR), and its content uniformity and short-term stability were measured and investigated. Then, water content and residue on ignition of impurity A were determined, and its purity was determined using high performance liquid chromatography (HPLC) with 10 mmol/L ammonium acetate solution-acetonitrile (98∶2) as the mobile phase. Mass balance method was used to determine the content of the first batch of tazobactam impurity A national standard substance. Meanwhile, nuclear magnetic quantitative method was used to calculate the content, which was mutually verified with the mass balance method. The developed reference material of tazobactam impurity A is consistent with the maximum degradation impurity in tazobactam system applicability solution and the reference material of tazobactam related substance A contained in USP41. Within the 95% confidence range, the ratio of inter- and intra-bottle variance of impurity A after separation was 0.61 (< F0.05(11,12)), proving that the uniformity was satisfying. The contents of organic impurity, water content and inorganic impurity in impurity A were 0.90%, 1.24% and 0.25%, respectively. The content of impurity A was determined to be 97.6% by mass balance method, which was basically consistent with the result of nuclear magnetic quantitative method (97.1%). Under the condition of 25 °C, the area normalized purity of impurity A was 99.1% at 0, 3, 5 and 10 days, proving that the sample was stable at room temperature for 10 days. Finally the first batch of national standard substance of tazobactam impurity A was established successfully.

Non-alkaloid constituents of Hymenocallis littoralis / 中国中药杂志

Perennial herb Hymenocallis littoralis(Amaryllidaceae) boasts anti-tumor, anti-virus, and anti-inflammatory activities. As the representative constituents, alkaloids have attracted much attention, whereas the non-alkaloid constituents have been rarely reported. Therefore, this study investigated the non-alkaloid constituents of H. littoralis and their contribution to the various pharmacological activities of the herb. Thirteen non-alkaloid compounds were isolated from the 95% ethanol extract of dried whole plant of H. littoralis after a series of chromatographic separation steps and spectral analysis, and they were identified as 5,7-dihydroxy-6,8-dimethoxy-2-hydroxymethyl-4H-chromoen-4-one(1), undulatoside A(2),(2S)-7,4'-dihydroxyflavane(3), naringenin(4), 4',7-hydroxy-8-methylflavanone(5), 8-methylnaringenin(6), 8-demethylfarrerol(7), 6-methyl-aromadendrin(8), 4',5,7-trihydroxy-8-methylflavanone(9), syzalterin(10), 6-methylapigenin(11), isoliquiritigenin(12), and undatuside C(13) based on the spectroscopic data analysis. Among them, compound 1 was a new chromone derivative, and compounds 2 and 4-13 were isolated form this plant for the first time.

Two new monoterpenoids of Zingiber officinale peel / 药学学报

The chemical constituents of Zingiber officinale peel were isolated and purified by various chromatographic separation techniques such as Diaion HP-20, MCI Gel CHP-20, Sephadex LH-20, ODS, silica gel and semi-preparative HPLC. Seven terpenoids were identified by physicochemical properties and spectral data: (4R,6S)-1-(hydroxymethyl)-5,5-dimethylbicyclo[3.1.1]hept-2-en-4-ol (1), 4-(hydroxymethyl)-1-isopropylcyclohex-2-ene-3,4-diol (2), 3,5,6-trihydroxy-7-megastigmen-9-one (3), 3-(3-hydroxybutyl)-2,4,4-trimethyl-2,5-cyclohexadien-1-one (4), angelicoidenol (5), grasshopper ketone (6), and dihydrophaseic acid (7), in which compounds 1, 2 are new compounds, named: (4R,6S)-1-(hydroxymethyl)-5,5-dimethylbicyclo[3.1.1]hept-2-en-4-ol and 4-(hydroxymethyl)-1-isopropylcyclohex-2-ene-3,4-diol, and compounds 3-7 were obtained from this plant for the first time.

Identification of related substances of midazolam hydrochloride by LC-MS / 中国药科大学学报

@#This study aimed to identify the related substances of midazolam hydrochloride by liquid chromatography-mass spectrometry (LC-MS). To separate the related substances of midazolam hydrochloride, gradient elution was performed using acetonitrile and 25 mmol/L of ammonium acetate (pH was adjusted to 5.5 with acetic acid) as mobile phase on Thermo BDS Hypersil C18 column (100 mm × 4.6 mm, 2.4 μm). The accurate mass and elemental composition of the parent ions and their product ions of related substances were determined by electrospray-ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF/MS). The structures of the related substances were identified by spectral analysis and process synthesis, and some of them were further confirmed by reference substances. Under the established HPLC condition, midazolam hydrochloride and its related substances were adequately separated, and 22 major related substances were detected and identified by hyphenated techniques in midazolam hydrochloride and its stressed samples, of which 8 were recorded as impurities in the United States Pharmacopeia. The LC-MS techniques can effectively separate and identify the related substances of midazolam hydrochloride and provide reference for the establishment of storage condition, optimization of synthetic processes and quality control.

Taxane diterpenoids from the leaves and stems of Taxus wallichiana var. mairei / 中国药科大学学报

@#The chemical constituents of the CHCl3 extracts from the leaves and stems of Taxus wallichiana var. mairei were investigated. Twelve taxane diterpenoids were isolated and identified by spectroscopic analysis as 2-deacetoxytaxinine E (1),2-deacetoxytaxinine J (2),7-deacetoxytaxinine J (3),taxinine J (4),7,2′-didesacetoxyaustrospicatine (5),N-methyltaxol C (6),2-deacetoxydecinnamoyl taxinine J (7),taxol (8),7-epi-taxol (9),7-epi-10- deacetoxytaxol (10),cephalomannine (11),7-epi-cephalomannine (12). Compounds 1 and 3 were isolated from the leaves and stems of Taxus wallichiana var. mairei for the first time.

Phenolic Glycosides from the Aerial Part of Urena lobata / 中国药学杂志

OBJECTIVE: To study the phenolic glycosides of Urena lobata. METHODS: Compounds were isolated and purified using various column chromatographies such as D101 macroporous adsorption resin, silica gel, Sephadex LH-20, and preparation HPLC. Their structures were established using extensive spectroscopic techniques such as MS and NMR. The anti-inflammatory activities of all compounds were evaluated by using LPS-stimulated RAW264.7 cells. RESULTS: Twelve phenolic glycosides were obtained from the n-BuOH extract of U. lobata including benzyl-7-O-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (1), phenylethyl-8-O-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (2), phenylethyl-8-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (3), eugenyl-1-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (4), 6-methoxyeugenyl-1-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (5), 3,4,5-trimethoxybenzene-1-O-α-L-rhamnosyl-(1→6)-β-D-glucopyranoside (6), 4-O-(glycer-2-yl)-dihydroconiferylalcohol-1′-O-β-D-mannopyranoside (7), benzyl-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (8), 3,5-dimethoxy-4-hydroxyphenylethyl-8-O-β-D-glucopyranoside (9), 3,4,5-trimethoxybenzene-1-O-β-D-glucopyranoside (10), phenylethyl-8-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside(11),and 3,4,5-trimethoxybenzene-1-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (12). CONCLUSION: Compounds 2-8 and 10-12 are obtained from the family Malvaceae for the first time, and compounds 3, 8, 9 and 11 show moderate inhibition of nitric oxide production in LPS-stimulated RAW264.7 cells, with IC50values of(40.5±4.9 ), (31.9±4.6),( 37.7±3.3 ), and (36.1±4.6 )μmol•L-1, respectively.

Chemical constituents from the stems of Clerodendrum trichotomum Thunb / 中国药科大学学报

@#Thirteen compounds were isolated and purified from the ethanol extract of Clerodendrum trichotomum Thunb. by various chromatographic methods. Their structures were identified as friedelin(1), betulinic acid(2), taraxerol(3), platanic acid(4), acacetin(5), 5, 7-dihydroxy 3′, 4′-dimethoxyflavone(6), β-sitosterol(7), stigmasterol(8), daucosterol(9), stigmasterol-3-O-glucopyranoside(10), isovanillin(11), dibutyl phthalate(12)and syringaldehyde(13). Compounds 4, 6, 11- 13 were isolated from genus Clerodendrum Linn. for the first time. Compounds 4, 6, 10- 13 were isolated from Clerodendrum trichotomum Thunb. for the first time.

Isolation and identification of antitumor constituents from Trichosanthes tricuspidata / 中国药科大学学报

@#Ten compounds were isolated and purified from the dichloromethane fraction of Trichosanthes tricuspidata roots by silica gel and ODS column chromatographies. Their chemical structures were identified on the basis of their physical and chemical properties as well as the spectral data. These isolated compounds were elucidated as khekadaengoside O(1), a new hexanorcucurbitane glycoside, together with nine known compounds, including khekadaengoside C-E, K(2-5), cucurbitacin J-2-O-β-glucopyranoside(6), cucurbitacin K-2-O-β-glucopyranoside(7), cucurbitacin B, J, K(8-10). In addition, the anti-tumor activity of compounds 1-10 were evaluated in hepatocellular carcinoma BEL-7402 cell line. Among them, compounds 8-10 showed potent antitumor activity.

Isolation and Identification of Chemical Constituents from Cinnamomi Ramulus / 中国实验方剂学杂志

Objective:The research group found in the early stage that the 75%alcohol extract of the Cinnamomi Ramulus had a significant physiological activity in inhibiting necroptosis by screening out the self-built sample library of 100 kinds of traditional Chinese medicines in Jiangxi. To identify the active components and find the target compounds,the 75%alcohol extracts of Cinnamomi Ramulus were isolated and studied systemically in chemistry. Method:The 20 kg dry Cinnamomi Ramulus was crushed into coarse powder,and extracted with 75%alcohol for four times, one time every 7 d. Then total extracts were obtained after solvent was recycled under decompression. The extract was separated by D101 macroporous resin column chromatography and eluted by water,30%ethanol,50%ethanol,70%ethanol,90%ethanol,so as to get the corresponding fraction finally. The compounds in the 30%ethanol and 50%ethanol fraction were isolated and purified by chromatography on silica gel,Sephadex LH-20 column and high pressure preparative chromatography,and their structures were determined according to physicochemical properties and spectral analysis. Result and Conclusion:Thirteen compounds were isolated and identified as (+)-syringaresinol (1),(+)-lyoniresinol (2),spicatolignan B (3),(-)-secoisolariciresinol (4),ovafolinin B (5),protocatechualdehyde (6),protocatechuic acid (7),syringaldehyde (8),vanillic acid (9),ethyl protocatechuate (10),syringic acid (11),ethyl gallate (12),2-(3',4'-dihydroxyphenyl)-1,3-pepper ring-5-aldehyde (13). Compounds 1-5,10-13 were isolated from this plant for the first time.

Studies on chemical constituents of Isodon henryi / 中国中药杂志

The chemical constituents of the water extraction of the aerial parts of Isodon henryi were investigated by various chromatographic methods including D-101 macroporous adsorptive resins,silica gel,sephadex LH-20,and semi-preparative HPLC. As a result,ten compounds were separated and purified. By analyses of the UV,IR,MS,NMR spectra,their structures were determined as rabdosinate( 1),lasiokaurin( 2),epinodosinol( 3),rabdosichuanin C( 4),epinodosin( 5),hebeirubescensin k( 6),rubescensin C( 7),enmenol( 8),oridonin( 9),and enmenol-1-β-glucoside( 10). Compounds 1-8 and 10 were isolated from I. henryi for the first time. Compounds 2 and 9 showed inhibitory effects against four tumor cells,with IC50 values of 2. 25-9. 32 μmol·L-1.

Chemical Constituents of Drynaria fortunei and Their Protective Effects on PC12 Cell / 中国药学杂志

OBJECTIVE: To study the chemical constituents from the rhizome of Drynaria fortunei and the protective effects of them on PC12 cells induced by Aβ25-35. METHODS: The compounds were isolated and purified by silica gel, Sephadex LH-20, ODS column chromatography, and their structures were identified on basis of spectroscopic METHODS:, such as MS and NMR. PC12 cells were treated with Aβ25-35 to establish the Alzheimer' s disease models. The compounds of different concentrations were added into culture medium to detect the protection. MTT assay was used to detect cell vitality and to observe the protective effects of compounds on PC12 cells induced by Aβ25-35. RESULTS: Nine compounds were isolated and identified as naringin(1), neoeriocitrin(2), 5,7-dihydroxychromone-7-neohesperidoside(3), (E)-4-O-β-D-glucopyranosyl caffeic acid(4), kaempferol(5), luteolin(6), protocatechoic acid(7), psoralen(8), and β-sitosterol(9). The cell experiments were performed on the compounds 1-8 and the RESULTS: showed they can promote the proliferation of PC12 cells. The cell vitality increase with concentration rising, and the difference is statistically significant (P<0.05). CONCLUSION: Compounds 1-8 play an important role in protecting Aβ25-35-induced injury in PC12 cells and they are the main active components of Drynaria fortunei in the protection of central nervous function.

Chemical Constituents from Citrus aurantium L / 中国药学杂志

OBJECTIVE: To study the chemical constituents of Citrus aurantium L. METHODS: Chromatographic techniques were employed for isolation and purification of the constituents and their structures were determined by spectral analysis and chemical evidence. RESULTS: Sixteen compounds were obtained and identified as pyrrolezanthine-6-methyl ether (1), methyl 3-hydroxy-4-methoxybenzoate (2), 3-hydroxy-4-methoxybenzoic acid (3), methyl 3,4-dihydroxybenzoate (4), methyl 3-(4-acetoxyphenyl)propanoate (5), 4-hydroxybenzoic acid (6), scopoletin (7), 5-(hydroxymethyl)furan-2-carbaldehyde (8), hesperidin (9), naringin (10), gossypetin-8,3'-dimethylether-3-O-β-D-galactoside (11), 2-homoeriodictyol-7-O-β-D-glucopyranoside (12), 6-demethoxytangeretin (13), naringenin (14), 5,6,7,8,4'-pentamethoxyflavone (tangeretin) (15), and 5-O-desmethylnobiletin (16). CONCLUSION: Compounds 124811-13 are for the first time obtained from Citrus.

Chemical constituents from the leaves of Anisopus mannii and the melanogenesis inhibitory activities / 中国药科大学学报

@#The phytochemical studies on the leaves of Anisopus mannii led to the isolation of seven compounds by silica gel, ODS, DIAION HP-20, Sephadex LH-20 colunmn chromatographer, their structures were elucidated on the basis of the spectroscopic analyses(NMR, HRMS)and the comparisons with the literatures as 3β-acetoxylup-20(29)-ene(1), 1-acetoxy-2-isopropyl-1-tridecene(2), rutin(3), 3, 6′-diferuloylsucrose(4), 3-O-β-D-glucopyranosyl-3-β-hydroxyolean-12-en-28-oic acid 28-O-［α-L-rhamnopyra- nosyl-(1→2)-β-D-glucopyranosyl］ ester(5), conduritol A(6), hoyacarnoside I(7). Meanwhile, the isolated compounds were evaluated for their inhibitory activities against melanogensis in B16 melanoma cells, as the results, all compounds exhibited melanogenesis-inhibitory activity and compound 5 showed a strongest activity(Melanin content: (27. 4±3. 5)%, Cell Viability: (54. 9±5. 6)% with a concentration of 30 μmol/L)which could be further developed.

Study on the Chemical Constituents in the Chloroform Extract of Fructus Canarii / 中国药房

OBJECTIVE:To study the chemical constituents in the chloroform extract of Fructus Canarii. METHODS:The chloroform extract of Fructus Canarii was isolated and purified by MCI,Toyopearl HW-40F,reverse-phase C18,Sephadex LH-20 column. The structure of compounds was analyzed and identified by physicochemical properties and spectral data(mass spectrum, hydrogen spectrum and carbon spectrum). RESULTS:Eight compounds were isolated from chloroform extract of Fructus Canarii, namely Dihydrophaseicacid-3′-O-β-D-glucopyranoside(1),3,4-Dihydroxybenzoic acid(2),3-O-galloylquinic acid(3),Gallic acid (4), Ethyl gallate(5), Scopoletin(6), Dllagic acid-4-O-α-L-rhamnopyranoside(7) and Isocorilagin(8). CONCLUSIONS:Compounds 1,2 and 7 were firstly obtained from Fructus Canarii. The study lays foundation for quality evaluation of Fructus Canarii.

Study on Chemical Constituents of Ethanol Extract from Cirtus aurantium / 中国药房

OBJECTIVE: To study the chemical constituents of ethanol extract from Cirtus aurantium. METHODS: The ethanol extract of C. aurantium was isolated and purified by silica gel column, open ODS column, preparation liquid chromatography, HW-40F gel column and macroporous resin column. The structure of compounds was analyzed and identified according to physicochemical properties and spectral data (mass spectrum, hydrogen spectrum, carbon spectrum). RESULTS: Eight compounds were isolated from ethanol extract of C. aurantium, i. e. Rimboxo (1), Thymidine (2), Uracil (3), Cyclo-(Leu1-Ile2-Ala3-Thr4-Gly5-Thr6-Phe7) (4), Cyclo- (Leu1-Leu2-Pro3-Tyr4-Gly5-Ser6-Pro7) (5), Meranzin hydrate-β-D-glucoside (6), Umbelliferone (7), Linaloyl glucoside (8). CONCLUSIONS: Compound 1, 2, 3, 8 are isolated from Citrus L. for the first time, compound 4, 5, 6 were isolated from C. aurantium for the first time. The study lays the foundation for quality evaluation of C. aurantium.