罗红霉素在犬体内的代谢转化罗红霉素在犬体内的代谢转化

目的考察罗红霉素在犬体内的代谢转化及po和iv给药途径对药物代谢的影响。方法采用液相色谱-质谱(LC-MSⁿ)联用技术,检测在iv或po给予单剂量罗红霉素后犬胆汁中的罗红霉素及其代谢物。代谢物经LC/MSⁿ方法分离和分析,并通过与对照品比较质谱和色谱行为确定其结构。结果共检测到13种罗红霉素代谢物,包括N-去甲基和N, N-双去甲基衍生物、肟醚侧链O-去烷醚基衍生物、脱红霉糖衍生物、罗红霉素及其代谢物的Z式几何异构体衍生物。结论罗红霉素在犬体内主要经历4种代谢途径;罗红霉素及其代谢物的几何异构与脱红霉糖代谢在口服和注射两种给药途径间存在显著的差异。     

(9S)-9-羟基-12-亚甲基红霉素A衍生物的合成

为了合成具有抗菌活性的红霉素衍生物,本文以红霉素A为原料,合成了6-位烯丙基取代中间体12,21-双键-2′-O,4″-O-二苯甲酰基-(9S)-9-O,11-O-异丙基-6-O-烯丙基红霉素A 12,得到(9S)-9-羟基-12-亚甲基衍生物6和6,7-去氢-(9S)-9-羟基-12-亚甲基衍生物11。经¹³C NMR,FAB-MS确证产物结构。所得化合物进行了体外抗菌活性测定。6和11均显示出较弱的抑菌活性。     

(9S)-12-亚甲基红霉素衍生物的合成及体外抗菌活性

目的合成新的具有抗菌活性的红霉素衍生物。方法以红霉素为原料，合成中间体2′-O,4″-O-二苯甲酰基-(9S)-9-O,11-O-异丙基-12-亚甲基红霉素与6,7-去氢-2′-O,4″-O-二苯甲酰基-(9S)-9-O,11-O-异丙基-12-亚甲基红霉素，进而合成相应(9S)-9-O,11-O-亚乙基-12-亚甲基衍生物。产物结构经¹³C NMR,FAB-MS确证。对所得化合物进行体外抗菌活性测定。结果制备11个红霉素衍生物，其中5个未见文献报道。化合物9和12进行了体外抗菌活性测定。结论化合物9和12表现出较弱的抗菌活性。     

荚果蕨贯众化学成分研究

目的对荚果蕨贯众的化学成分进行研究。方法用色谱法分离化合物，根据理化性质和光谱数据鉴定结构。结果分离鉴定了4个化合物：1-O-β-D-葡糖基-(2S,3R,4E，8Z)-2-N-(2′-羟基二十二碳酰)-二十碳鞘氨醇-4,8-二烯(1)，1-O-β-D-半乳糖-(6→1)-α-D-半乳糖-2,3-O-十六烷酸甘油二酯(2)，丁二酸(3)，D-甘露糖醇(4)。结论 化合物1和2为新化合物，3和4为首次从该植物中分离得到。     

大鼠粪样中山莨菪碱及其代谢物的串联质谱法检测

目的运用液相色谱-电喷雾串联质谱(LC-MSn)法检测大鼠粪样中山莨菪碱及其代谢物。方法收集灌胃山莨菪碱(25 mg·kg^-1)的大鼠粪样,用水浸泡后,以乙酸乙酯萃取,采用LC-MS及LC-MSn等方法检测原药及其代谢物。根据代谢物相对分子质量的变化(ΔM)及其多级质谱数据,鉴定并阐述其结构,同时与空白粪样及山莨菪碱相比较。结果在服药后的大鼠粪样中发现山莨菪碱及其7种代谢产物, 分别为6β-羟基托品、N-去甲基-6β-羟基托品、N-去甲基脱水山莨菪碱、脱水山莨菪碱、N-去甲基山莨菪碱、羟基山莨菪碱以及托品酸等。结论该方法灵敏、快速、简便、有效,适合于生物样品中的药物及其代谢产物的快速鉴定。     

芝麻花化学成分的研究

芝麻花为胡麻科植物胡麻Sesamum indicum L.(S.orientale L.)的干燥花,有生发、消肿之功效,可治疗脱发、冻疮、便秘等。民间单方芝麻花治疗寻常疣、扁平疣等,均有满意的疗效。目前人们对芝麻种子的化学成分研究较多,但尚没有人对芝麻花的化学成分进行系统研究。本研究运用硅胶柱、凝胶柱、反相柱等多种色谱方法进行分离纯化,并根据理化性质和波谱数据鉴定化合物的结构。从其乙醇提取物的乙酸乙酯和正丁醇部位分别得到10个化合物,分别鉴定为latifonin (1),苦瓜脑苷(momor-cerebroside,2),大豆脑苷II(soya-cerebroside II,3),1-O-β-D-葡糖-(2S,3S,4R,5E,9Z)-2-n-(2′-羟基二十四碳酰氨基)-1,3,4-三羟基-十八碳-5,9-二烯［1-O-β-D-glucopyranosyl-(2S,3S,4R,5E,9Z)-2-n-(2′-hydroxytetra-cosanoyl) 1,3,4-trihydroxy-5,9-octadienine,4］,1-O-β-D-葡糖-(2S,3S,4R,8Z)-2N-(2′-羟基二十四碳酰氨基)-3,4-二-羟基-8-十八碳烯［1-O-β-D-glucopyranosyl-(2S,3S,4R,8Z)-2-n-(2′R) 2′-hydroxytetracosanoyl)-3,4-dihydroxy-8-octadene,5］,2-乙酰橙酰胺［(2S,1″S)-aurantiamide acetate,6］,苯基乙醇-O-(2′-O-β-D-吡喃鼠李糖,3′-O-β-D-吡喃葡糖)-β-D-吡喃葡糖［benzyl alcohol-O-(2′-O-β-D-xylopyranosyl, 3′-O-β-D-glucopyranoside)-β-D-glucopyranoside,7］,β-谷甾醇(8),胡萝卜苷(9),D-半乳糖醇(10)。其中化合物4为新化合物,所有化合物均为首次从该植物的花中分离得到。     

太平洋侧花海葵中四个新神经酰胺的鉴定太平洋侧花海葵中四个新神经酰胺的鉴定

目的研究太平洋侧花海葵(Anthopleura pacifica)中的生物活性成分。方法采用稻瘟霉模型生物活性追踪方法,应用色谱技术进行分离,根据理化性质和波谱分析鉴定结构。结果得到了1个对稻瘟霉显示活性的组分,并鉴定为4个神经酰胺的混合物:N-羟乙基-N-十四酰-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(a),N-羟乙基-N-(9Z-十六烯酰)-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(b),N-羟乙基-N-十六酰-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(c)和N-羟乙基-N-(13Z-二十二烯酰)-(2S,3R)-十八碳鞘氨醇-4(E),8(E)-二烯(d)。结论化合物a～d均为新的神经鞘氨醇化合物。     

LC/DAD/MSD技术研究大鼠胆汁中盐酸非洛普的II相代谢产物

目的研究大鼠服药后胆汁中盐酸非洛普(DDPH)II相代谢产物.方法收集大鼠空白胆汁及给药后12h内的胆汁,以LC/DAD/MSD技术判断II相代谢产物峰位.以HPLC法制备II相代谢产物馏分并以β-葡糖醛酸酶水解,再进行分析;同时将与II相代谢产物相应的I相代谢产物对照品按相同条件进行分析对照.结果大鼠给药后胆汁色谱图中峰M₇,M₈和M₉为DDPH的II相代谢产物,它们的β-葡糖醛酸酶水解产物分别为M₃,M₂和M₁.结论β-1-O-{3,5-二甲基-4-[-2-甲基-2-(3,4-二甲氧基苯乙氨基)-乙氧基]-苯基}-葡糖醛酸(M₇),β-1-O-{2,4-二甲基-3-[2-甲基-2-(3,4-二甲氧基苯乙氨基)-乙氧基]-苯基}-葡糖醛酸(M₈)和β-1-O-{2-甲氧基-4-[1-甲基-2-(2,6-二甲基苯氧基)-乙氨基-乙基]-苯基}-葡糖醛酸(M₉)为大鼠ipDDPH后产生的II相代谢产物.     

拟人参皂苷F11在大鼠体内的药物代谢研究

目的探讨拟人参皂苷F11在大鼠体内的药物代谢产物及其过程.方法ip拟人参皂苷F₁₁后,应用TLC分析排泄物中的代谢产物,并利用制备薄层分离制备代谢产物,通过波谱解析(MS,¹HNMR,¹³CNMR,¹H-¹HCOSY)确定其结构.结果从粪便中分离鉴定了3种代谢产物,分别为拟人参皂苷R_T5,ocotillol和1个新的代谢产物F-3-1,并确定其结构为6-O-α-L-吡喃鼠李糖基(1-2)-β-D-吡喃葡糖基-(20S,23S,24R)-达玛-20(24)-环氧-3β,6α,12β,23,25-五醇(6-O-α-L-rhamnopyranosyl-(1-2)-β-D-glucopyranosyl-(20S,23S,24R)-dammar-20(24)-epoxy-3-β,6α,12β,23,25-pentanol).但在尿液和胆汁中并未发现任何代谢产物.结论拟人参皂苷F₁₁不被肝脏代谢,但胆汁排泄物可在肠道被代谢为水解和氧化产物.     

顺式-和反式-阿霍烯在Caco-2细胞模型中的体外摄取、转运和外排特性

研究顺式-阿霍烯(Z-Ajo)和反式-阿霍烯(E-Ajo)的肠细胞摄取、转运和外排特性。采用体外培养的人结肠Caco-2细胞单层模型评价，应用高效液相色谱法测定Z-Ajo和E-Ajo的含量。结果表明，仅能在Caco-2细胞单层的顶侧检测到Z-Ajo或E-Ajo；阿霍烯在Caco-2细胞中的代谢可被抗氧化剂维生素C、细胞色素P450药物代谢酶3A亚型抑制剂甲吡酮和ATP抑制剂叠氮化钠所抑制。Z-Ajo和E-Ajo皆不能透过Caco-2单层细胞而被迅速代谢，其代谢与CYP450药物代谢酶有关。     

Identification of the metabolites of roxithromycin in humans.

The semisynthetic antibiotic roxithromycin (RXM) exists in an (E)-configuration. Metabolites of RXM in the bile of four cholecystectomy patients with T-tube drainage and in the urine and plasma of four healthy volunteers after single oral doses of 150 mg of RXM were investigated. A total of 15 metabolites were found in bile, urine, and plasma by HPLC with ion trap mass spectrometric and electrochemical detection. These metabolites were identified as descladinose derivative of RXM (M1), erythromycin-oxime (M2), N-, O-, and N,O-di-demethylated derivatives of RXM (M3, M4, and M6), and N-mono- and N-di-demethylated derivatives of erythromycin-oxime (M5 and M7), as well as the (Z)-isomers (M8-M15) of RXM and metabolites M1 to M7, respectively. Structures of six major metabolites (M1-M4, M8, and M10) were established by chromatographic and mass spectrometric determination and comparison with synthesized standards. The stability of RXM and the six synthesized substances was investigated to exclude artifact products. These results, together with previous findings, suggest that biotransformation pathways elucidated for RXM include: 1) isomerization of RXM derivatives, from E-isomer to Z-isomer; 2) O-demethylation; 3) N-demethylation; 4) hydrolysis of the cladinose moiety; and 5) dealkylation of the oxime ether side chain. Secondary metabolism via these pathways was also evidenced. The O-demethylation and isomerization of RXM derivatives represent two novel biotransformation pathways recovered for RXM.     

Microbial production of phase I and phase II metabolites of propranolol

1. The production in multimilligram amounts of 4- and 5-hydroxylated metabolites of (R)- or (S)-propranolol by biotransformation with two fungal strains, an Absidia sp. M50002 and a Cunninghamella sp. M50036, was carried out, starting from either the racemic drug or pure enantiomers.

2. While both enantiomers of propranolol were hydroxylated in the 5-position by incubation with strain M50002, the strain M50036 operated a chiral discrimination, resulting in the exclusive formation of the 4-hydroxy-(R)-enantiomer.

3. In addition, a Streptomyces sp. strain M52104, isolated from a soil sample, was selected for the high-yield regioselective β-glucuronidation of propranolol and its 4- and 5-hydroxylated derivatives.

4. NMR and mass spectroscopic data have been extensively used for the unambiguous characterization of 4- and 5-hydroxylated and glucuronidated derivatives, all of them corresponding to the major animal and human metabolites of propranolol, a typical substrate of CYP2D6.

     

Metabolites of isocorynoxeine in rats after its oral administration

This work presents the metabolites of isocorynoxeine (ICOR), which is one of four bioactive tetracyclic oxindole alkaloids isolated from Uncaria hooks used commonly in the traditional Chinese medicines and Kampo medicines. After oral administration of 40 mg kg^? 1 ICOR to rats, bile was drained and analyzed by LC-MS. Two phase I metabolites, namely 11-hydroxyisocorynoxeine (M1) and 10-hydroxyisocorynoxeine (M2), and two phase II metabolites, namely 11-hydroxyisocorynoxeine 11-O-β-d-glucuronide (M3) and 10-hydroxyisocorynoxeine 10-O-β-d-glucuronide (M4), were isolated from rat excreta and bile, respectively, whose structures were elucidated on the basis of CD, NMR, and MS.     

Metabolism of the antineoplastic and immunosuppressive drug 2-CdA (Leustatin®) in animals and humans

1. The in vivo metabolism of the antineoplastic and immunosuppressive drug 2-CdA (Leustatin®) was investigated in mice, monkeys and humans after a single subcutaneous dose of cladribine 60?mg?kg^?1 to eight male and eight female mice and 10?mg?kg^?1 to one male and one female monkey, and an intravenous infusion dose of cladribine 22–45 mg^?1 per subject to 12 male patients.

2. Plasma (1?h), red blood cells (1?h) and faecal samples (0–24?h) were obtained from mice and monkeys, and urine samples (0–24?h) were obtained from these species and humans.

3. Unchanged cladribine (urine: 47%?of the sample in human; 60%?of the sample in mouse; 73%?of the sample in monkey) and 10 metabolites, consisting of four phase I metabolites (M1–3, M7) and six phase II metabolites—five glucuronides (M4, M6, M8–10) and one sulfate (M5)?—?were profiled, characterized and tentatively identified in plasma, red blood cells, and faecal and urine samples on the basis of API ionspray-mass spectrometry (MS) and MS/MS data.

4. Metabolites were formed via the following three metabolic pathways: oxidative cleavage at the adenosine and deoxyribose linkage (A); oxidation at adenosine/deoxyribose (B); and conjugation (C).

5. Pathways A and B appear to be major steps, forming four oxidative/cleavage metabolites (M1–3, M7) (each 3–20%?of the sample).

6. Pathway C along or in conjunction with pathways A and B produced cladribine glucuronide, cladribine sulfate and four glucuronides of oxidative/cleavage metabolites in minor/trace quantities (each?≤?5%?of the sample).

7. In addition, the in vitro metabolism of cladribine was conducted using rat and human liver microsomal fractions in the presence of an?β-nicotinamide adenine dinucleotide phosphate-generating system. Unchanged cladribine (≥?90%?of the sample) plus three minor metabolites, M1–3 (each?8. Cladribine is not extensively metabolized in vitro and in vivo in all species. However, humans appear to metabolize cladribine to a greater extent than other animals.     

Investigation of 6-O-methyl-scutellarein metabolites in rats by ultra-flow liquid chromatography/quadrupole-time-of-flight mass spectrometry

Context Scutellarin (1) has been widely used in China to treat acute cerebral infarction and paralysis induced by cerebrovascular diseases. However, scutellarin (1) has unstable metabolic characteristics.

Objective The metabolic profile of 6-O-scutellarein was studied to determine its metabolic stability in vivo.

Materials and methods In this study, a method of UFLC/Q-TOF MS was used to study the 6-O-methyl-scutellarein metabolites in rat plasma, urine, bile and faeces after oral administration of 6-O-methyl-scutellarein (3). One hour after oral administration of 6-O-methyl-scutellarein (3) (34?mg/kg), approximately 1?mL blood samples were collected in EP tubes from all groups. Bile, urine and faeces samples were collected from eight SD rats during 0–24?h after oral administration. The mass defect filtering, dynamic background subtraction and information dependent acquisition techniques were also used to identify the 6-O-methyl-scutellarein metabolites.

Results The parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces. The glucuronide conjugate of 6-O-methyl-scutellarein (M1, M2), diglucuronide conjugate of 6-O-methyl-scutellarein (M3), sulphate conjugate of 6-O-methyl-scutellarein (M4), glucuronide and sulphate conjugate of 6-O-methyl-scutellarein (M5), methylated conjugate of 6-O-methyl-scutellarein (M6) were detected in rat urine. M1, M2 and M3 were detected in rat bile. M1 was found in rat plasma and M7 was detected in faeces.

Discussion and conclusion Because the parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces, we speculate that 6-O-methyl-scutellarein (3) had good metabolic stability in vivo. This warrants further study to develop it as a promising candidate for the treatment of ischemic cerebrovascular disease.     

Identification of etazene (etodesnitazene) metabolites in human urine by LC-HRMS

Etazene (or etodesnitazene) is a novel and highly active synthetic opioid belonging to the rapidly evolving and emerging group of “nitazenes.” Etazene metabolites were identified through analysis of a human urine sample. The sample was obtained from a 25-year-old man who attempted suicide by taking a new psychoactive substances (NPS) cocktail purchased online and was analyzed by ultrahigh performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS). Etazene metabolites were predicted with BioTransformer 3.0, and the exact masses were added to the inclusion list. Eight possible metabolites were identified in the urine sample. N- and O-deethylation were identified as the predominant metabolism routes, resulting in M1 (O-deethylated etazene; most abundant metabolite based on the peak area), M2 (N-deethylated etazene), and M3 (N,O-dideethylated etazene) metabolites. Less abundant hydroxylated products of these deethylated metabolites and etazene were also found. Additionally, in the analysis without β-glucuronidase treatment, M1- and M3-glucuronide phase II metabolites were found. As N- and O-deethylated products seem to be the predominant urinary metabolites, the detection of these metabolites in urine can be useful to demonstrate etazene exposure.     

Three new polyunsaturated lipids from a Guangxi marine sponge Haliclona sp.

Three new polyunsaturated lipids, (6Z,9Z,12Z,15Z)-octadeca-6,9,12,15-tetraen-3-one (1), (6Z,9Z,12Z,15Z)-1-bromooctadeca-6,9,12,15-tetraen-3-one (2), and (Z)-ethyl docos-5-enoate (3), together with two known polyunsaturated lipids, 4(Z),7(Z),10(Z)-tridecatrienoic acid (4) and (6Z,9Z,12Z,15Z)-octadeca-1,6,9,12,15-pentaen-3-one (5), were isolated from the marine sponge Haliclona sp., which was collected from Guangxi, using HSCCC and HPLC methods. Chemical structures of the five compounds were elucidated by spectroscopic techniques.     

Inhibition of human catechol-O-methyltransferase-mediated dopamine O-methylation by daphnetin and its Phase II metabolites

1.?Finding and developing inhibitors of catechol-O-methyltransferase (COMT) from natural products is highly recommended. Daphnetin, a naturally occurring catechol from the family thymelaeaceae, has a chemical structure similar to several potent COMT inhibitors reported previously. Here the potential of daphnetin and its Phase II metabolites as inhibitors of COMT was investigated with human liver cytosol (HLC).

2.?Daphnetin and its methylated metabolite (8-O-methyldaphnetin) were found to inhibit COMT-mediated dopamine O-methylation in a dose-dependent manner. The IC₅₀ values for daphnetin (0.51～0.53?μM) and 8-O-methyldaphnetin (22.5～24.3?μM) were little affected by changes in HLC concentrations. Further kinetic analysis showed the differences in inhibition type and parameters (K_i) between daphnetin (competitive, 0.37?μM) and 8-O-methyldaphnetin (noncompetitive, 25.7?μM). Other metabolites, including glucuronidated and sulfated species, showed negligible inhibition against COMT. By using in vitro–in vivo extrapolation (IV-IVE), a 24.3-fold increase in the exposure of the COMT substrates was predicted when they are co-administrated with daphnetin.

3.?With high COMT-inhibiting activity, daphnetin could serve as a lead compound for the design and development of new COMT inhibitors. Also, much attention should be paid to the clinical impact of combination of daphnetin and herbal preparations containing daphnetin with the drugs primarily cleared by COMT.     

Identification of domperidone metabolites in plasma and urine of gastroparesis patients with LC–ESI-MS/MS

Abstract

1. Domperidone is a prokinetic agent used to treat gastroparesis. Previous studies reported oxidative metabolites of domperidone, detected by radiometric high-performance liquid chromatography or single quadrupole mass spectrometric techniques. Our aim was to identify domperidone Phase I and Phase II metabolites using liquid chromatography combined with electrospray ionization-enabled tandem mass spectrometry.

2. Domperidone metabolites were identified in the plasma and urine of 11 gastroparesis patients currently being treated with domperidone. In addition, oxidative and conjugative metabolites of domperidone were characterized in human liver subcellular fractions.

3. Seven metabolites were detected in vivo. Domperidone was metabolized to two mono-hydroxylated metabolites (M1 and M2), a de-alkylated metabolite (M5) and a di-hydroxylated metabolite (M7). The mono-hydroxylated metabolites were further glucuronidated to M8, M9 and sulfated to M11. To the best of our knowledge, M7, M8, M9 and M11 have not been reported previously. Five additional metabolites were identified in vitro in human subcellular fractions which comprise two additional mono-hydroxylated metabolites (M3 and M4), an alcohol metabolite (M6) possibly formed from an aldehyde intermediate, and other conjugative metabolites (M10 and M12). M6, M10 and M12 have not been characterized previously.

4. In total, 12 domperidone metabolites including 7 new metabolites were identified in the present study. These results allow a better understanding of domperidone disposition in humans.     

The metabolism of 4-bromoaniline in the bile-cannulated rat: application of ICPMS (79/81Br), HPLC-ICPMS & HPLC-oaTOFMS

Abstract

1.?An excretion balance study was performed following i.p. administration of 4-bromoaniline (50?mg kg^?1) to bile-cannulated rats, using bromine-detected (^79/81Br) ICPMS for quantification. Approximately 90% of the dose was recovered in urine (68.9?±?3.6%) and bile (21.4?±?1.4%) by 48?h post-administration.

2.?HPLC-ICPMS (^79/81Br) was used to selectively detect and profile the major urinary and biliary-excreted metabolites and determined that the 0–12?h urine contained at least 21 brominated metabolites with 19 bromine-containing peaks observed in the 6–12?h bile samples.

3.?The urinary and biliary metabolites were subsequently profiled using HPLC-oaTOFMS. By exploiting the distinctive bromine isotope pattern ca. 60 brominated metabolites were detected in the urine in negative electrospray ionisation (ESI) mode while bile contained ca. 21.

4.?While a large number of bromine-containing metabolites were detected, the profiles were dominated by a few major components with the bulk of the 4-bromoaniline-related material in urine accounted for by 4-bromoanaline O-sulfate (～75% of the total by ICPMS, 84% by TOFMS). In bile a hydroxylated N-acetyl compound was the major metabolite detected, forming some ～65% of the 4-bromoaniline-related material by ICPMS (37% by TOFMS).