乌拉尔甘草三萜——甘乌内酯的化学结构

自乌拉尔甘草(Glycyrrhiza uralensis Fisch.)根茎总皂甙元中,分得一微量新三萜成分,根据IR,UV,MS,¹HNMR,¹³CNMR等光谱及NOE,COSY,NOESY,INEPT等实验方法确定结构为3β,22α-digydroxy-11-oxo-Δ¹²-olean-ene-27α-methoxy carbonyl-29-oic acid(29,22α-)lactone。命名为甘乌内酯(glyuranolide)。     

异叶梁王茶化学成分的研究

从异叶梁王茶[Nothopanax davidii(Franch)Harms]树皮中分离得到两种五环三萜皂甙,经化学和光谱(IR,¹HNMR,¹³CNMR,¹H-¹H COSY,¹H-¹³C COSY,NOESY,MS)分析,分别鉴定为3-O-α-(3′,4′-O-二乙酰基)-L-吡喃阿拉伯糖-β-羟齐墩果-12-烯-28,29-双羧酸-28-O-[α-L-吡喃鼠李糖(1→6)-β-D-吡喃葡萄糖(1→4)-β-D-吡喃葡萄糖]酯甙(Ⅱ)和3-O-α-(3′-O-乙酰基)-L-吡喃阿拉伯糖-3β-羟齐墩果-12-烯-28,29-双羧酸甙(Ⅱ),前者命名为异叶梁王茶甙Ⅰ,后者命名为异叶梁王茶甙Ⅱ。这两个皂甙均系新化合物。     

辽藁本化学成分的研究

从辽藁本(Ligusticum jeholense Nakai et Kitagawa)根及根茎的95%乙醇提取物的石油醚—乙醚(1∶1)及乙醚溶解部分用常压、低压柱层析及制备薄层层析法,共分离得到5个化合物,经光谱解析(IR,MS,¹HNMR,¹³CNMR,¹H-¹³CCOSY,¹H-¹HCOSY,DEPT,HMBC和NOE差谱)及标准品对照,确定其中一个为新化合物,命名为新藁本内酯(I)。另外4个已知化合物分别为藁本内酯(II),4-羟基-3-甲氧基-苯乙烯(III),阿魏酸(IV)和β-谷甾醇(V),并对II的¹³CNMR谱进行了重新归属,使之更为合理。     

中药路路通化学成分的研究

目的研究中药路路通(Fructus liquidambaris)的化学成分。方法用色谱法分离路路通的化学成分,根据理化性质和波谱数据鉴定其结构。结果分离得到11个化合物,分别鉴定为:β-谷甾醇(1),3-oxo-11α,12α-epoxyoleanan-28,13β-olide (2),3-oxo-12α-hydroxy-oleanan-28,13β-olide (3),3α-acetoxyl-25-hydroxyolean-12-en-28-oic acid (4),齐墩果酸(5),熊果酸(6),胡萝卜苷(7)桦木酮酸(8),没食子酸(9),正二十九烷(10),正三十烷酸(11)。结论4为新化合物,3为首次从天然产物中分离得到,5,6,7,9,10和11为首次从路路通中分离得到。     

无毒棉花籽中黄酮苷的分离与结构鉴定

目的　研究无毒棉花籽(glandlesscottonseed)中的黄酮类化学成分。方法　利用大孔树脂、聚酰胺-6、硅胶和SephadexLH-20柱色谱进行分离纯化。用UV ,MS ,¹HNMR ,¹³CNMR ,¹H-¹HCOSY ,¹H-¹³CCOSY ,HMBC和TOCSY等光谱确定化合物结构。结果　从无毒棉花籽中分离得到5个黄酮苷,经光谱鉴定化合物结构为:山奈酚-3-O-β-D-芹菜糖( 1→2 )-[α-L-鼠李糖(1→6)]-β-D-葡糖苷(I)、槲皮素-3-O-β-D-芹菜糖 ( 1→2)-[α-L-鼠李糖( 1→6)]-β-D-葡糖苷(II)、槲皮素-3-O-β-D-芹菜糖 ( 1→2 )-β-D-葡糖苷(III)、芦丁(IV)和陆地棉苷(V)。结论　I是一个新化合物,II和III为首次从该属植物中分离得到。     

大环骨架结构的倍半萜化合物——Ⅵ.马兜铃新内酯的化学结构测定

自绵毛马兜铃(Aristolochia mollissima Hance)根茎中分得九个化合物,其中已报道的七个化合物是尿囊素、马兜铃内酯、绵毛马兜铃内酯、β-谷甾醇、马兜铃酸A、9-乙氧基马兜铃内酯和9-乙氧基马兜铃内酰胺,本文报道结晶K₃的化学结构,经光谱分析(IR,¹H-NMR,¹³C-NMR,2D-NMR和MS),化学反应及X-衍射晶体分析,确证K₃为一个新骨架结构的倍半萜化合物,命名为马兜铃新内酯。     

异叶梁王茶甙Ⅲ和Ⅳ的结构

继前报后,又从异叶梁王茶[Nothopanax davidii(France)Harms]树皮中分离得到两种五环三萜皂甙。经化学和波谱(IR,¹HNMR,~(13)CHMR,¹H-¹HCOSY,¹³C-¹H COSY,MS)分析,分别鉴定为3-O-α-(2’,4’-O-二乙酰基)-L-吡喃阿拉伯糖-3β-羟基齐墩果-12-烯-28,29-双羧酸-28-O-[α-L-吡喃鼠李糖(1-4)-β-D-吡喃葡萄糖(1—6)-β-D-吡喃葡萄糖]酯甙(Ⅲ),命名为异叶梁王茶甙Ⅲ和3-O-β-(2-O-乙酰基)-D-吡喃木糖-3β-羟齐墩果-12-烯-28,29-双羧酸甙(Ⅳ),命名为异叶梁王茶甙Ⅳ。这两种皂甙均系首次从植物中分出的新化合物。     

3′(5α-3β,17β-双羟基-雄甾烷-17α)-丙酸内酯(Ⅴ)的微生物转化——螺旋内酯甾(Ⅱ)的合成

3′-(5α-3β,17β-双羟基-雄甾烷-17α)-丙酸内酯(Ⅴ)经诺卡氏菌(Nocardia sp.)转化获得6个化合物(Ⅱ和Ⅵ～Ⅹ),其中螺旋内酯甾(Ⅱ)为其主要产物(～50%)。Ⅷ～Ⅹ是尚未被鉴定的羟基化合物。化合物(Ⅴ)用诺卡氏菌在氮源贫乏的培养基中转化主要生成△⁴-3-酮化合物,而在氮源丰富的培养基中转化则主要为△^1,4-3-酮的产物。     

金钱草中黄酮苷的分离与结构鉴定金钱草中黄酮苷的分离与结构鉴定

目的从金钱草中分离制备标准品。方法用硅胶柱色谱进行分离,通过理化方法及IR,UV,MS,¹HNMR,¹³CNMR,DEPT,HMQC,HMBC等光谱分析确定化合物结构。结果从金钱草中分离得到2个化合物,分别鉴定为鼠李酮酸γ-内酯(I)、山奈酚-3-O-α-L-鼠李糖(1→2)-β-D-木糖苷(II)。结论II为新化合物,命名为金钱草素,I为首次从该属植物中分离得到。     

虎眼万年青的化学成分

目的：研究栽培于长白山区的虎眼万年青Ornithogalum caudatum Ait全草的化学成分。 方法：用各种色谱技术进行分离和纯化,用ESIMS,IR,¹HNMR,¹³CNMR,DEPT,¹H-¹H COSY, ¹H-¹³C COSY, HMBC和NOESY等波谱数据分析鉴定结构。结果：从虎眼万年青全草中分离得到3个化合物,其中化合物I为新化合物,其结构鉴定为（25S, 23S, 24S）-螺甾-Δ⁵⁽⁶⁾-烯-1β, 3β,23,24-四醇-1-O-α-L-吡喃鼠李糖基-（1→2） ［β-D-吡喃木糖基-(1→3)］-α-L-吡喃阿拉伯糖苷(I),另外2个已知化合物为海柯皂苷元-3-O-{β- D-吡喃葡糖基（1→2）-［β-D-吡喃木糖基（1→3）］-β-D-吡喃葡糖基（1→4）-β-D-吡喃半乳糖苷}(II)和β-谷甾醇(III)。结论：化合物I为新化合物,命名为虎眼万年青苷A,化合物II和III是首次从该植物中分得的已知化合物。     

Stability and Release Performance of a Series of Pegylated Copolymeric Micelles

Purpose. The aim of this work is to evaluate the capability of a series of biocompatible amphiphilic copolymers as a nano-sized drug carrier. Methods. The influences of the type of lactone monomer, the feed molar ratios of lactone/PEG, and the molecular weight of PEG on the performance and release behavior of micelles are investigated. Results. These pegylated amphiphilic copolymers efficiently form micelles with a low CMC value in the range of 10^–6-10^–7 M. The average particle size of micelles is 100 nm. The phenomenon of increasing particle size as increasing the chain length of poly(lactone) block is observed. The different hydrophobicity, based on chemical structure of poly(lactone), accounts for different interaction strength between indomethacin and hydrophobic inner core, which further influences the drug loading in copolymeric micelles and their release character. In addition, the PCL/PEG/PCL micellar solutions maintain their sizes at 4°C for 8 weeks without occurring significant aggregation or dissociation. Conclusions. A series of biocompatible pegylated amphiphilic copolymers have been elucidated possessing micellization potential to form nano-sized micelles in an aqueous environment, which enable incorporate hydrophobic drug and regulate drug release.     

The Acidic Microclimate in Poly(lactide-co-glycolide) Microspheres Stabilizes Camptothecins

Purpose. The camptothecin (CPT) analogue, 10-hydroxycamptothecin (10-HCPT) has been shown previously to remain in its acid-stable (and active) lactone form when encapsulated in poly(lactide-co-glycolide) (PLGA) microspheres (1). The purpose of this study was to determine the principal mechanism(s) of 10-HCPT stabilization. Methods. CPTs were encapsulated in PLGA 50:50 microspheres by standard solvent evaporation techniques. Microspheres were eroded in pH 7.4 buffer at 37°C. The ratio of encapsulated lactone to carboxylate was determined by HPLC as a function of time, initial form of drug encapsulated, fraction of co-encapsulated Mg(OH)₂, CPT lipophilicity, and drug loading. Two techniques were developed to assess the microclimate pH, including: i) measurement of H⁺ content of the dissolved microspheres in an 80:20 acetonitrile/H₂O mixture and ii) confocal microscopy of an encapsulated pH-sensitive dye, fluorescein. Results. The encapsulated carboxylate converted rapidly to the lactone after exposure to the release media, indicating the lactone is favored at equilibrium in the microspheres. Upon co-encapsulation of Mg(OH)₂, the trend was reversed, i.e., the lactone rapidly converted to the carboxylate form. Measurement of -log(hydronium ion activity) (pa*_H) of dissolved microspheres with pH-electrode and pH mapping with fluorescein revealed the presence of an acidic microclimate. From the measurements of H+ and water contents of particles hydrated for 3 days, a microclimate pH was estimated to be in the neighborhood of 1.8. The co-encapsulation of Mg(OH)₂ could both increase the pa*_H reading and neutralize pH in various regions of the microsphere interior. Varying the drug lipophilicity and loading revealed that the precipitation of the lactone could also stabilize CPT. Conclusions. PLGA microspheres prepared by the standard solvent evaporation techniques develop an acidic microclimate that stabilizes the lactone form of CPTs. This microclimate may be neutralized by co-encapsulating a base such as Mg(OH)₂, as suggested by previous work with poly(ortho esters) (2).     

野菊花成分的研究(第二报) 野菊花内酯的化学結构

由野菊花(Chrysanthemum indicum L.)分离得一新内酯化合物C₁₅H₁₈O₄暂名为野菊花内酯(yejuhua lactone),本文证明系属洋甘菊薁烃(chamazulene)的母核。部分梏构式为(Ⅰ)。     

Plasma Pharmacokinetics of the Lactone and Carboxylate Forms of 20(S)-Camptothecin in Anesthetized Rats

20(S)-Camptothecin exists in equilibrium between its lactone (CPT) and its carboxylate forms (Na-CPT) under simulated physiological conditions, with the equilibrium favoring the carboxylate form. The rates of lactone hydrolysis were studied in plasma, serum albumin, and blood and were found to be faster than in aqueous buffers at equivalent pH values. From mechanistic information and in vivo activity data, the lactone appears to be the active form of the drug. It has been argued, therefore, that if an equilibrium existed between the lactone and the carboxylate, Na-CPT could be used to deliver the lactone effectively. In the present study, plasma pharmacokinetics were performed in sodium pentobarbital-anesthetized rats treated with both CPT (lactone) and the sodium salt of camptothecin (carboxylate, Na-CPT) and the lactone and carboxylate, as well as the total drug, concentration versus time profiles were assessed. It was found that plasma concentrations and AUC values for the lactone were significantly higher after dosing with CPT than after dosing with Na-CPT. After i.v. administration, the ratio of plasma lactone to carboxylate was skewed by the apparent rapid and extensive uptake of the lactone into tissues and the rapid clearance of both species. From our results, it appears that the lower in vivo activity of Na-CPT compared to that from CPT administration might be attributed to the altered conversion of carboxylate into lactone in vivo compared to that predicted from in vitro data.     

吐温80对9-硝基喜树碱脂质体药物动力学性质的影响

目的:考察吐温80对9-硝基喜树碱(9-NC)脂质体体内药物动力学以及内酯型/羧酸盐型平衡的影响。方法:采用薄膜法制备9-NC脂质体以及吐温80修饰的9-NC脂质体;12只大鼠随机分为两组,按1.5 mg.kg-1剂量分别给予9-NC普通脂质体和吐温80修饰的脂质体,于不同时间点取血,处理后测定9-NC内酯型浓度和总浓度(内酯/羧酸盐)。采用统计矩模型利用3P97程序计算药物动力学参数。结果:采用表面活性剂吐温80进行修饰后,9-NC内酯型和总浓度的AUC分别提高了1.47倍和1.65倍,内酯型和总浓度的清除率CL和表观分布容积Vss显著下降(P<0.01)。此外,总浓度的MRT以及t1/2延长(P<0.05)。结论:吐温80修饰使得9-NC内酯型比例有所下降,但没有显著性差异,9-NC吐温修饰对9-NC脂质体具有一定的长循环效果。     

Intramolekulare Aromatenalkylierungen, 17. Mitt. Synthese von trans-3,10b-Dimethyl-1,2,3,4,4a,5,6,10b-octahydrobenzo(f)isochinolin

Intramolecular Alkylations of Aromatic Compounds, XVII¹⁾: — Synthesis of trans-3,10b-Dimethyl-1,2,3,4,4a,5,6,10b-octahydrobenzo(f)isoquinoline From the cyanhydrine 5b , easily obtained from 4 and trimethylsilyl cyanide, the lactone 6 is prepared, hydrogenation of which gives a mixture of the lactam 7a and the lactone 8 . Compound 7a is reduced to the secondary base 9 , which by treatment with acid is dehydrated to 10 and rearranges to give the isomer 11 , too. Attempted cyclization of the aminoalcohol 12 fails to give 9 or 10 . Rather, the furan 13 is isolated as the final product. N-methylation 10 → 14 and subsequent hydrogenation furnish the 4:1 trans/cis-mixture 2a, b , from which the title compound is separated by column chromatography. From 11 the stereomers 18a, b can be prepared analogously.     

Chemical and enzymatic treatment of endothelin

Endothelin-1 (ET), the most potent vasoconstrictor yet discovered, is a peptide containirig 21 amino acids with two intrachain disulfide bridges. With the aim of obtaining two-chain derivatives, Et was submitted to chemical and enzymatic treatments. Reaction of ET with CNBr in 70% HCOOH gave, in addition to the expected [Hse⁷ lactone]-7,8-seco-ET and unreacted material, a by-product whose molecular weight was 25 m.u. greater than that of ET. When the reaction mixture, after lyophilisation, was immediately quenched with NH3-saturated dry MeOH, two products could be recovered in a 5:1 ratio, both obtained by nucleophilic attack of the homoserine lactone: the expected [Hse⁷-NH₂]-7,8-seco-ET and [Hse⁷]ET, resulting from competitive intramolecular reaction of the deprotonated α-amino group of the Asp⁸ residue. The Lys⁹-Glu¹⁰ bond turned out to be very resistant to enzymatic attack both by Lys-C-endopeptidase and trypsin. The 9,10-seco-ET derivative could be obtained by treatment with Lys-C-endopeptidase only by using a high enzyme/ET ratio and after a prolonged incubation time. Cleavage of the Lys⁹-Glu¹⁰ bond could not be achieved by treatment with trypsin, even with a high enzyme/substrate ratio. The main product was 13, 14-seco-ET, deriving from the action of chymotripsin (present as an impurity in the trypsin preparation) on Tyr¹³. The structure of these peptides was confirmed by amino-acid sequence analysis and fast atom bombardment mass spectrometry (FAB-MS). Nicking of the ET structure at different positions had different impact on the biological properties of the resulting derivatives. © Munksgaard 1995.     

绵毛马兜铃化学成分研究——Ⅳ.绵毛马兜铃内酯的化学结构测定

从马兜铃属植物绵毛马兜铃Aristolochia mollissima Hance根茎中分得9种(Ⅰ～Ⅸ)成分,其中结晶Ⅲ为一新倍半萜内酯,用光谱法测定了化学结构,命名为绵毛马兜铃内酯Mollislactone,晶Ⅰ为尿囊素,晶Ⅱ为马兜铃内酯,晶Ⅳ为β-谷甾醇,晶Ⅸ为马兜铃酸,其余成分尚在研究中。     

Slow O,N-acyl shift in an actinomycin-related peptide lactone

The pentapeptide lactone Cbz-(Thr-D-Val-Pro-Sar-MeAla-) was synthesized in order to observe the behavior of the unprotected lactone resulting from its hydrogenolytic deprotection. Closely related peptide lactones have been reported as intermediates in total syntheses of actinomycin D and its analogues, despite the fact that unprotected and unprotonated O-peptides of serine and threonine are known to undergo rapid O,N-acyl shift. In the present study the peptide lactone was seen to undergo a slow O,N-acyl shift, in a matter of hours, to the known cyclic pentapeptide. This contrasted with the rapid rearrangement of a model O-peptide, O-hippuryl-L-threonine methyl ester. This slowness of an O,N-acyl shift in a cyclic system presumably results from higher energy barriers of conformational origin. It explains the suitability of unprotected peptide lactones for the syntheses of actinomycins and other peptide lactone antibiotics which have appeared in the literature.     

石虎的化学成分研究

由石虎果实的酸性乙醇提取物中分得五种单纯成分。其中四种经鉴定为吳萸內酯(Evodin或Limonin)、吳萸碱、去甲基吳萸碱和羟基吳萸碱。最后一种暂命名为石虎甲素[C₁₈H₁₈O₆,熔点262℃,[a]_D³⁰-65.5°(c=0.061,氯仿)],可使溴的冰醋酸溶液褪色,紫外和红外吸收光谱表明为不饱和酮