得自小根蒜及薤中的几种含氮化合物

从中药薤白的主要基源植物小根蒜（ＡｌｌｉｕｍｍａｃｒｏｓｔｅｍｏｎＢｕｎｇｅ）鳞茎中首次分得５种化合物。它们是腺苷（Ａｄｅｎｏｓｉｎｅ，１）、胸苷（Ｔｈｙｍｉｄｉｎｅ，２）、２，３，４，９－四氢－１－甲基－１Ｈ－吡啶骈［３，４－ｂ］吲哚－３－羧酸（２，３，４，９－ｔｅｔｒａｈｙｄｒｏ－１－ｍｅｔｈｙｌ－１Ｈ－ｐｙｒｉｄｏ［３，４－ｂ］ｉｎｄｏｌｅ－３－ｃａｒｂｏｘｙｌｉｃａｃｉｄ，３）、２，３，４，９－四氢－１Ｈ－吡啶骈［３，４－ｂ］吲哚－３－羧酸（２，３，４，９－ｔｅｔｒａｈｙｄｒｏ－１Ｈ－ｐｙｒｉｄｏ［３，４－ｂ］ｉｎｄｏｌｅ－３－ｃａｒｂｏｘｙｌｉｃａｃｉｄ，４）和丁香甙（Ｓｙｒｉｎｇｉｎ，５）．从另一种基源植物薤（Ａ．ｃｈｉｎｅｎｓｅＧ．Ｄｏｎ）鳞茎中分得腺苷（１）、色氨酸（Ｔｒｙｐｔｏｐｈａｎ，６）和化合物（４）．     

绞股蓝同属植物和制剂中有效成份分离及含量测定方法概述

70年代日本开发了葫芦科植物绞股蓝（GynostemmaPenlaphyllun（Thunb．）Makino）为医疗保健品后，我国在80年代相继发展了众多的绞股蓝产品。近年来药理研究证明有抗衰老、抗疲劳、降低过氧化脂质、抑制肿瘤细胞、降低血脂、防治胃溃疡和肾上腺皮质机能减退［‘］、促进细胞新陈代谢、强壮补益、调理神经等有一定疗效，同时具有副作用小、作用级和等优点＊］。目前国外学者已从绞股蓝植物中分离出82种皂忒［’］，其中6种和人参皂忒相同，是迄今为止在五茄科以外发现含有人参皂忒的唯一植物［‘］。如绞股蓝皂忒巨，IV，W，VI，分别与…     

(±)-二氢猕猴桃内酯的合成研究

二氢猕猴桃内酯（ｄｉｈｙｄｒｏａｃｔｉｎｉｄｉｏｌｉｄｅ,１）是从猕猴桃属木天蓼（Ａｃｔｉｎｉｄｉａｐｏｌｙｇａｍａ）［１］、茶叶及烟草［２］等植物中分离得到的一种天然产物,是茶叶和烟草香气的重要成份。该化合物表现出植物毒性等生理活性［３］,能够抑制植物的生长。Ｔｏｒｒｉ等［４,５］以香叶醇为原料,经溴化、苯磺酰化、羧基化、环化和脱苯磺酰基５步反应合成了１。但该路线步骤较多,反应条件苛刻,操作复杂。如：羧基化反应需在无水、无氧和低温（－７８℃）的条件下进行;脱苯磺酰基反应则要在３５０℃的高温下反…     

吴茱萸化学成分的研究

吴茱萸化学成分的研究唐元清，冯孝章，黄量（中国医学科学院、中国协和医科大学药物研究所，北京１０００５０）中药吴茱萸（Ｅｖｏｄｉａｒｕｔａｅｃａｒｐａ［Ｊｕｓｓ］Ｂｅｎｔｈ）为芸香科植物吴茱萸干燥将近成熟的果实，有温中散寒、疏肝止痛之功效￣［１］，常用...     

半夏、草乌、马钱子的炮制经验

半夏为天南星科半夏属植物半夏［Pinelliaternata（Thumb）Breit．］的球状块茎,别名三叶半夏,辛温有毒,有化痰,止咳、燥湿、止呕作用。草乌为毛莫科植物乌头（AconiturncarmichaeliDEBx.）的块根,辛热剧毒,有祛风湿、散寒、止痛作用。马钱子为马钱科植物马钱［Strychnosnux－VomicaL．］,以干燥成熟种子入药。性苦寒,有大毒。有通经络,消结肿,止痛作用。这3种中药均有毒性,必须经炮制后才能供药用,现将炮制方法简介如下。半夏先将原药泡7～8d,每天换2次,泡至舌稍有麻辣感为度。另取生姜、白矾粉含半夏拌匀,置蒸笼内蒸sh…     

比浊法测定磺胺甲哐恶唑及复方片剂中磺胺甲哐恶唑的含量

磺胺甲哐恶唑（ｓｕｌｆａｍｅｔｈｏｘａｚｏｌｅＳＭＺ）为一种中效具广谱抗菌作用的磺胺类药物。磺胺甲哐恶唑常与磺胺增效剂甲氧苄啶（ｔｒｉｍｅｔｈｏｐｐｒｉｍＴＭＰ）合用,称复方磺胺甲哐恶唑片（复方新诺明）,已报导的含量测定有永停滴定法［１］、分光光度法［１］、ＨＰＬＣ法［２］、比色法［３］等。这些方法有的所需仪器较昂贵,有的操作较复杂,难掌握。参考有关文献［４］并通过试验发现：磺胺甲哐恶唑中的硫在碱性介质中可被Ｈ２Ｏ２（３０％）催化氧化为硫酸盐,可用比浊法测定磺胺甲哐恶唑及其复方片剂中ＳＭＺ的含量…     

天然产物研究中的人工产物

植物中的萜类、生物碱等类成分由于提取分离过程中溶剂或外界光热等作用反应而生成植物本身并不含有的成分,称为人工产物。对分离所得的纯物质需进行仔细分析,确定是人工产物还是植物本身含有的成分。例如,早在５０年代,傅丰永等［１］从秦艽根中提取出３个生物碱［１～３］：秦艽碱甲（２,ｇｅｎｔｉａｎｉｎｅ）、秦艽碱乙（２′,ｇｅｎｔｉａｎｉｄｉｎｅ）和秦艽丙素（３,ｇｅｎｔｉａｎａｌ）。但随后的研究［４～５］表明,秦艽的乙醇提取液中没有秦艽碱甲等３个生物碱,而含有龙胆苦苷（１）,龙胆苦苷在氨水中转化生成秦艽碱…     

山茱萸中的单没食子酰景天庚酮糖苷

山茱萸为山茱萸科植物（ＣｏｒｎｕｓｏｆｆｉｃｉｎａｌｉｓＳｉｅｂ．ｅｔＺｕｃｃ．）的干燥成熟果肉,为常用中药,有补肝肾、涩精气、强壮、收敛等功效［１］。山茱萸总苷有明显的免疫抑制活性［２,３］,能抑制小鼠淋巴细胞转化,抑制ＬＡＫ细胞生成和白细胞介素?..     

毛细管电泳法及其在生物碱分析中的应用

生物碱是植物中一类重要的化学成分,在植物中分布较广。至少有５０多科１２０属以上的植物中已证明有生物碱存在［１］,已知的生物碱种类至少在３０００种以上［２］。生物碱类化合物大多具有生理活性,往往是许多药用植物,包括许多中草药的主要有效成分,如阿片中的镇痛成分吗啡,麻黄中抗哮喘成分麻黄碱和黄连中的抗菌消炎成分小檗碱等。生物碱的分析方法很多,其中高效液相色谱法（ＨＰＬＣ）是目前最常用的方法［３］。由于ＨＰＬＣ色谱柱易被中药中的其他成分污染,而且不易再生,因此要求在样品前处理时尽可能地除去干扰成分,这就…     

土茯苓化学成分研究(IV)

土茯苓为百合科植物光叶菝契（ＳｍｉｌａｘｇｌａｂｒａＲｏｘｂ．）的干燥根，分布于华东及西南地区，有解毒、除湿、利关节等功效，为中医临床常用中药［１］。文献报道［２～４］其提取物有选择性抑制细胞免疫反应，预防兔心率失常，抗动脉粥样硬化；从土茯苓中分得的...     

Synthesis and evaluation of 2,6-piperidinedione derivatives as potentially novel compounds with analgesic and other CNS activities

New 2,6-piperidinediones 2_a–g and 4_a–d were prepared by initial condensation of aromatic aldehydes or cycloalkanones with cyanoacetamide to give α-cyanocinnamides l_a–g or cycloalkylidenes 3_a,b which underwent Michae1 addition with ethyl cyanoacetate or diethylmalonate. Compounds 4_a–d were alkylated by various alkyl halides to produce the N-alkylated 2,6-piperidinedione derivatives 5_a–m. Some new selected compounds 2_a–c,f, 4_a–d & 5_e,h,j were pharmacologically evaluated for potential anticonvulsant, sedative and analgesic activities. These compounds exhibited significant anticonvulsant and analgesic effects after a single I.P. administration 100 mg/kg b.wt. . On the other hand all the investigated compounds induced hypnotic activity and prolonged the phenobarbital sodium- induced sleep as compared with the control group and the most potent compound was found to be 2_f.     

NEURAMIDE STIMULATES ADRENOCORTICOTROPIN BUT NOT PROLACTIN RELEASE FROM RAT PITUITARY

Neuramide (NMD), a substance found in crude preparations of porcine stomach extract, is a viral inhibitor that also has putative immunostimulatory effects. The effects of NMD on stress-hormone (ACTH and prolactin—PRL) release were assessed inin vivoandin vitrostudies. In the former, blood levels of corticosterone and PRL were measured in NMD-treated male rats.In vitroexperiments were performed to evaluate the effects of NMD and three of its fractions (obtained with high performance liquid chromatography) on ACTH and PRL release from perfused rat pituitary slices. NMD increased plasma corticosterone levelsin vivoand produced dose-dependent increases inin vitropituitary release of ACTH. No effects on PRL secretion were observedin vivoorin vitro. The stimulatory effects on ACTH release were caused by the NMD fraction with a molecular weight of >5000<10000Da.     

EFFECT OF POLICOSANOL SUCCESSIVE DOSE INCREASES ON PLATELET AGGREGATION IN HEALTHY VOLUNTEERS

Policosanol is a cholesterol-lowering drug with hypocholesterolemic effects demonstrated in experimental models, healthy volunteers and type II hypercholesterolemic patients. In addition, antiplatelet effects of policosanol have been shown in experimental models and healthy volunteers. The effect of successively increasing doses of policosanol on platelet aggregation was investigated in a randomized, placebo-controlled, double-blind study conducted in 37 healthy volunteers. The volunteers were on a placebo-baseline period (two tablets per day) for 7 days and thereafter they received randomly, under double-blind conditions, placebo or policosanol (10mgday⁻¹) for 7 days. After this period dosage was doubled to 20mgday⁻¹for the next 7 days and then again doubled to 40mgday⁻¹, while the control group received placebo tablets all the time. Platelet aggregation as well as coagulation time was measured at baseline and after each dosing step. Results showed that antiplatelet effects of policosanol were successfully enhanced throughout the study, thus suggesting a dose-dependent relationship. No significant effect was reached during the first dosing period, but significant reductions of epinephrine and ADP-induced platelet aggregation were observed after the second one. Finally, a significant inhibition of platelet aggregation induced by all the agonists was observed at the last dosing step. Coagulation time remained unchanged during the trial.     

INDIRECT PARASYMPATHOMIMETIC ACTIVITY OF THE CLASS III ANTIARRHYTHMIC SUBSTANCE / -SOTALOLIN VITRO: REVERSIBLE INHIBITION OF CHOLINESTERASE ISOENZYMES FROM BLOOD AND THE HUMAN CENTRAL NERVOUS SYSTEM

Inhibitory effects of the class III antiarrhythmic compound / -sotalol on acetylcholinesterase (AChE; EC 3.1.1.7) isoenzymes of both erythrocytes and the human caudate nucleus and on serum cholinesterase (ChE; EC 3.1.1.8) were studiedin vitrousing a spectrophotometric kinetic assay with acetylthiocholine (ASCh) as substrate. Sotalol concentrations in the assays varied from 0.32 to 3.2m . All isoenzymes studied were inhibited by / -sotalol in a reversible and concentration-dependent manner. Double reciprocal plots of the reaction velocity against varying ASCh concentrations revealed that / -sotalol reduced substrate affinity (apparent Michaelis constant, KM, increased) of serum ChE, but did not change the enzyme's maximal rate of ASCh hydrolysis (V_max). Thus, / -sotalol inhibition of serum ChE was of the competitive type (rate constant for reversible competitive inhibition: K_i=0.51m ). In contrast, / sotalol reduced the maximal reaction velocity of the AChE isoenzyme from the central nervous system (caudate nucleus), but had no influence on substrate affinity of the enzyme (K_Mwith ASCh unchanged) indicating purely non-competitive inhibition kinetics (rate constant of reversible non-competitive inhibition: K_i′=0.44m ). / -sotalol inhibition of erythrocyte AChE was of mixed competitive/non-competitive type (K_i=0.31m , K_i′=0.49m ). Non-competitive / -sotalol inhibition of caudate nucleus AChE and the non-competitive component of erythrocyte AChE inhibition cannot be overcome by increased concentrations of the cholinergic transmitter acetylcholine (ACh). Peak / -sotalol plasma levels as described in the literature for both humans (15μ ) and experimental animals (dogs: 18μ ; rats: 260μ ) as well as maximal myocardial concentrations of the substance (dogs: 46μ ; rats: 478μ ) are in the range of about 2% to 100% of the sotalol inhibition rate constants determined in the present paper for cholinesterase isoenzymesin vitro. Thus, / -sotalol inhibition of ACh hydrolysisin vivomay contribute to both the well known antiarrhythmic potential and proarrhythmic side effects of the compound.     

鼻渊净胶囊的HPLC指纹图谱研究

目的 建立鼻渊净胶囊的高效液相色谱（HPLC）指纹图谱。方法 采用Agilent SB-C₁₈（4.6 mm×250 mm,5 μm）色谱柱,乙腈-水为流动相、以1.0 ml/min流速行梯度洗脱,检测波长210 nm,柱温30 ℃,洗脱时间为80 min。采用中药色谱指纹图谱相似度评价系统（2004A版）对检测出色谱进行指纹图谱相似度评价。结果 建立了鼻渊净胶囊的HPLC指纹图谱,确定了20个共有峰,15个峰归属到各药材,其中5个峰确认了化学成分;10批样品的指纹图谱的整体相似度与对照图谱比较,均在90%以上。结论 所建立的鼻渊净胶囊指纹图谱有助于从整体上控制该制剂的质量。     

Investigation of the prevalence of tetQ, tetX and tetX1 genes in Bacteroides strains with elevated tigecycline minimum inhibitory concentrations

In this study, the antibiotic susceptibilities to tigecycline and tetracycline of 35 selected Bacteroides fragilis group strains were determined by Etest, and the presence of tetQ, tetX, tetX1 and ermF genes was investigated by polymerase chain reaction (PCR). tetQ was detected in all 12 B. fragilis group isolates (100%) exhibiting elevated tigecycline minimum inhibitory concentrations (MICs) (≥8 μg/mL) as well as the 8 strains (100%) with a tigecycline MIC of 4 μg/mL, whilst tetX and tetX1 were present in 15% and 75% of these strains, respectively. All of these strains were fully resistant to tetracycline (MIC ≥ 16 μg/mL). On the other hand, amongst the group of strains with tigecycline MICs < 4 μg/mL (15 isolates), tetQ, tetX and tetX1 were found less frequently (73.3%, 13.3% and 46.7%, respectively). All but two strains harbouring the tetQ gene in this group were non-susceptible to tetracycline, with a MIC > 4 μg/mL. These data suggest that in most cases tigecycline overcomes the tetracycline resistance mechanisms frequently observed in Bacteroides strains. However, the presence of tetX and tetX1 genes in some of the strains exhibiting elevated MICs for tigecycline draws attention to the possible development and spread of resistance to this antibiotic agent amongst Bacteroides strains. The common occurrence of ermF, tetX, tetX1 and tetQ genes together predicted the presence of the CTnDOT-like Bacteroides conjugative transposon in this collection of Bacteroides strains.     

AMELIORIATION OF CHEMICALLY-INDUCED HEPATOCYTE INJURY BY CYCLOSPORINE A

Cyclosporine A, beside its current applications, possesses potential hepatoprotective effects. This study was directed to investigate the effect of Cyclosporine A pretreatment on hepatic injury due to carbon tetrachloride (CCl₄) and -galactosamine. Rats were injected by two successive doses of Cyclosporine A (5mgkg⁻¹day⁻¹). Six hours after the second dose, 1mlkg⁻¹of CCl₄was administered i.p. Effects associated with Cyclosporine A pretreatment were examined by using isolated hepatocytes and hepatocytes that were immobilized and continuously perfused. -Galactosamine (5m ) was added directly to the perfusion medium. After isolation, hepatocytes were examined histologically by light and electron microscopy, immobilized and perfused for further metabolic functional activity evaluation. Cyclosporine A pretreatmentin vivoproduced hepatoameliorative effects of various degrees which were statistically significant as manifested by: (1) an increased trypan blue exclusion after CCl₄; (2) an improved ureagenesis after CCl₄; (3) a reduction in the lipid droplets accumulation in the cytoplasm produced by CCl₄administration; (4) well preserved cytoplasmic organelles as mitochondria, endoplasmic reticulum ER, nuclear chromatin structures that were altered by CCl₄; and (5) an increased hepatocytes survival in the agarose gel matrix, reduction of LD leakage and improvement of ureagenesis after -galactosamine addition to the perfusion medium. The beneficial effect of Cyclosporine A pretreatment in modifying hepatotoxicity of chemical insults merits further studies.     

喙果黑面神化学成分研究

目的研究大戟科植物喙果黑面神(Breynia rostrata Merr.)的化学成分。方法利用硅胶、凝胶等色谱技术分离纯化化学成分,根据化合物的理化性质和光谱数据进行结构鉴定。结果从喙果黑面神的正丁醇萃取部分分离得到4个化合物,分别鉴定为6-O-甲基丙酰基-α-D-吡喃葡糖(6-O-methylpropanoyl-α-D-glucopyranose,1);4″-苯酚基-6-O-甲基丙酰基-β-D-吡喃葡糖苷(4″-phenolic-6-O-methylpropanoyl-β-D-glucopyranoside,2);1-O-没食子酰基-β-D-吡喃葡糖苷(1-O-galloyl-β-D-glucopyranoside,3);熊果苷(arbutin,4)。结论化合物1和2为新化合物,3和4均为首次从该种植物分离得到。     

EFFECTS OF 2-GUANIDINE-4-METHYLQUINAZOLINE ON GASTRIC ACID SECRETION IN RATS

In this study 2-guanidine-4-methylquinazoline (2-GMQ) appeared to decrease basal and stimulated gastric acid secretion, while structurally related compounds as dimethyl- biguanide, cyanoguanidine and 2-cyanoamino-4-methylpyrymidine did not. Thus, there is an antisecretory effect when the biguanide group is associated with a lipophilic structure. The antisecretive effects exerted by 2-GMQ are associated with anti H₂-histamine activity.The anti H₂-histamine nature of the effects of 2-GMQ was confirmed by the capacity of this compound of depressing the chronotropic activity of the isolated guinea pig auricle increased by histamine, as well as relaxant activity in rat uterus contracted by histamine, since both preparations are rich in H₂-histamine receptors.     

Effect of bay K 8644, a calcium channel agonist,on dog cardiac muscarinic receptors

To investigate further whether the effects of the dihydropyridine (DHP) drugs on calcium channels are related to those of these drugs on muscarinic receptors, the binding characteristics of the DHP calcium channel agonist, Bay K 8644, on muscarinic receptors and calcium channels were compared to those of the DHP calcium channel antagonists, nicardipine and nimodipine in the dog cardiac sarcolemma. Bay K 8644, nicardipine and nimodipine inhibited the specific [³H]QNB binding with K _i values of 16.7μM, 3.5μM and 15.5μM respectively. Saturation data of [³H]QNB binding in the presence of these DHP drugs showed this inhibition to be competitive. Bay K 8644, like nicardipine and nimodipine, blocked the binding of [³H]nitrendipine to the high affinity DHP binding sites, but atropine did not, indicating that the muscarinic receptors and the DHP binding sites on calcium channels are distinct. The K _i value of Bay K 8644 for the DHP binding sites was 4 nM. Nicardipine and nimodipine (K _i :0.1–0.2 nM) were at least 20 times more potent than Bay K 8644 in inhibiting [³H]nitrendipine binding. Thus, the muscarinic receptors were about 4000 times less sensitive than these high affinity DHP binding sites to Bay K 8644. These results suggest that the DHP calcium agonist Bay K 8644 binds directly to the muscarinic receptors but its interaction with the muscarinic receptors is not related to its binding to the DHP binding sites on calcium channels.