桉叶苷的分离和结构

目的　研究垂枝赤桉Eucalyptus camaldulensis var. pendula Blak. et Jacobs叶的化学成分。方法　采用各种色谱技术进行分离纯化,用IR, MS, ¹HNMR, ¹³CNMR(DEPT), ¹H-¹H COSY, ¹³C-¹H COSY, COLOC和X-射线单晶衍射鉴定化合物。结果　分离得到了5个化合物：三十烷醇(I),β-谷甾醇(II),对羟基苯甲酸(III), 胡萝卜苷(IV), 5,7-二羟基-2-甲基-苯骈吡喃酮-7-O-β-D-{6-O-［4R-(1-甲基-1-羟基)-乙基环己-1-烯］-甲酰基}-吡喃葡糖(V)。结论　所有化合物均为首次从该植物中分得,V为一个新化合物,命名为桉叶苷(camaldulenside)。     

叶下珠化学成分的研究

从叶下珠(Phyllantlais urinaria L.)的干燥全草中分得11个化合物。经光谱分析(UV,IR,¹HNMR,¹³C-NMR,¹H-¹H COSY,¹³C-¹H COSY,long range ¹³-¹H COSY,DEPT and MS)和化学反应等,鉴定了其中10个化合物,分别为正十八烷(Ⅰ),β-谷甾醇(Ⅲ),鞣花酸(Ⅳ),胡萝卜甙(Ⅴ),短叶苏木酚酸甲酯(methyl brevifolincarboxylate,Ⅵ),山萘素(Ⅶ),槲皮素(Ⅷ),去氢诃子次酸三甲酯(trimethyl ester dehydrochebulic acid,Ⅸ),没食子酸(Ⅹ),芸香甙(Ⅺ)。晶Ⅱ为一醛类化合物,结构正在鉴定中,晶Ⅵ和Ⅸ为新化合物。     

Production, isolation and biological activity of nargenicin from Nocardia sp. CS682

Culture broth of an actinomycete isolate, Nocardia sp. CS682 showed specifically higher antibacterial activity against methicilin resistant Staphylococcus aureus (MRSA). Purified substance from the organism, CS-682, which is active against MRSA and Micrococcus leuteus, is a C₂₈H₃₇NO₈ (M+H⁺, observed: 516.83) and identified as an unusual macrolide antibiotic, nargenicin. The chemical structure of CS-682 was identified by FT-IR, ¹H-NMR, ¹³C-NMR, and (¹H-¹H and ¹H-¹³H) COSY. The anti-MRSA activity of CS-682 was stronger than that of oxacillin, vancomycin, monensin, erythromycin, and spiramycin. Phylogenetic analysis showed that strain CS682 is closely related to Nocardia tenerifensis DSM 44704^T (98.7% sequence similarity), followed by N. brasiliensis ATCC 19296^T (98.4% sequence similarity). The ability of Nocardia sp. CS682 to produce nargenicin was unique.     

Tritium labeling of a γ‐secretase inhibitor and two modulators as in vitro imaging agents

The γ‐secretase inhibitor dibenzazepine ( DBZ ) and the γ‐secretase modulators 1 and AZ8349 were prepared as tritium‐labeled compounds with high specific activity and radiochemical purity. [³H] DBZ was labeled via an iodinated precursor, [³H] 1 was labeled by [³H]methylation of an O‐desmethyl precursor, and [2‐³H] AZ8349 was labeled via a tribromoacetyl precursor by catalytic hydrogenation. [³H]DBZ , [³H]1 , and [2‐³H]AZ8349 are promising in vitro imaging radioligands and have the potential to provide key information with regard to γ‐secretase expression, function, stoichiometry, and pharmacology.     

马尾松松针化学成分的研究

目的　研究松科植物马尾松(P.massoniana Lamb .)松针的化学成分。方法　利用色谱技术分离纯化,根据化合物的理化性质和光谱数据进行结构鉴定。结果　从马尾松针水煎液的正丁醇部位分离得到3个化合物,分别鉴定为:莽草酸(shikimicacid ,1) ,cedrusin [(7S ,8R)-3′,4 ,9,9′-四羟基-3- 甲氧基-7,8-二氢苯并呋喃-1′-丙醇基新木脂素,2],massonianoside B [(7S ,8R)-3 ,9,9′-三羟基-3-甲氧基-7,8-二氢苯并呋喃-1′-丙醇基新木脂素-4-O-α-L-鼠李糖苷,3]。结论　化合物3为新化合物,化合物1和2是首次从本植物中分离得到。     

[<Superscript>3</Superscript>H]LY334370, a novel radioligand for the 5-HT<Subscript>1F</Subscript> receptor. I. In vitro characterization of binding properties

[³H]LY334370 was developed as a radioligand to study the characteristics of this compounds interaction with the 5-HT_1F receptor. Monovalent or divalent cations did not enhance the binding of [³H]LY334370 to the cloned human 5-HT_1F receptor. In the presence of MgCl₂, the time to reach equilibrium was approximately 2 h, while in its absence equilibrium was reached in less than 1 h. [³H]LY334370 had high affinity for the cloned human 5-HT_1F receptor (K_d=0.446 nM) and the 5-HT_1F receptor in rat brain (K_d=0.388 nM). The expression density of 5-HT_1F receptors, as determined by binding to homogenates of cortical regions from rat, was low (B_max=79.1 fmol/mg protein). There was a statistically significant correlation between the apparent pK_i for inhibition of [³H]LY334370 binding and the pEC₅₀ for stimulation of [³⁵S]GTPS binding to homogenates of cells expressing the cloned human 5-HT_1F receptor. In addition, there was a statistically significant correlation between the apparent pK_i for inhibition of [³H]LY334370 binding to the cloned human 5-HT_1F receptor and the pID₅₀ for inhibition of trigeminal nerve stimulated dural plasma protein extravasation in the guinea pig. The conclusion from these studies is that [³H]LY334370 is a high affinity radioligand which can be used for the study of the 5-HT_1F receptor in rat brain or in cells transformed with the human 5-HT_1F receptor.     

四氢巴马汀等异喹啉生物碱对突触体及囊泡摄取[3H]多巴胺的影响

本文报道四氢巴马汀(THP)等异喹啉生物碱对[³H]DA摄取的作用。突触体对[³H]DA的亲和力常数Km为0.23μmol。最大摄取速率Vmax为1.2 nmol/g(5 min)。d-THP,1-SPD和1-THP对突触体摄取[³H]DA均有抑制作用,其IC₅₀分别为0.44,2.24和18.5μmol。d-THP的作用比1-THP约强20倍。nomifensine,苯丙胺和氟哌啶醇亦能有效地抑制[³H]DA摄取(IC₍₅₀₎分别为0.05,0.27和3.18μmol)。动力学研究表明,d-THP和nomifensine为DA摄取的竞争性抑制剂。用低渗溶液处理溶胀的方法研究药物对递质贮存的作用发现,与利血平相似,d-THP显著降低贮存囊泡[³H]DA含量并使囊泡与突触体[³H]DA含量之比明显减小。实验结果表明,THP等能抑制突触体摄取,并直接作用于贮存囊泡抑制[³H]DA贮存,因此具有利血平样排空作用。     

Synthesis of [3α‐3H] 17α‐Hydroxy pregnenolone and [3α‐3H] Pregnenolone

For the first time, [3α‐³H] 17α‐hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β‐³H] isomer in RP‐HPLC purified product was identified by tritium NMR. The [3β‐³H] isomer was then separated from [3α‐³H] 17α‐hydroxy pregnenolone with chiralPAK AD‐H column. [3α‐³H] pregnenolone (2) was synthesized from commercial available 5‐pregnen‐3,20‐dione in one step with an improved procedure.     

Synthesis of [3H,33P]‐phosphoramide and ‐isophosphoramide mustards and metabolites [3H]‐chloroethylaziridine and ‐aziridine for studies of DNA alkylation

Reduction of diethyliminodiacetate with [³H]‐LiAlH₄ and then reaction with SOCl₂ gave bis(2‐chloro‐2‐[³H]‐ethyl)amine hydrochloride. This compound, together with [³³P]‐phosphorus oxychloride, provided for the synthesis of [³H,³³P]‐phosphoramide mustard (as its cyclohexylammonium salt) in three steps over 2 days. Similarly, 2‐[³H]‐ethanolamine was reacted with SOCl₂ to give 2‐chloro‐2‐[³H]‐ethylamine hydrochloride which, along with [³³P]‐POCl₃, was used to synthesize [³H,³³P]‐isophosphoramide mustard in two steps over 1 day. ¹H NMR studies were carried out to determine optimal times for in situ formation and storage of chloroethylaziridine and aziridine. A solution of 10 mM bis(2‐chloroethyl)amine hydrochloride in 0.1 M phosphate/D₂O, pD 7.9 at 37°C for 3 h gave chloroethylaziridine without contamination by starting material or hydrolysis products. For aziridine, the disappearance of 0.2 M 2‐chloroethylamine hydrochloride in 2 M NaOD/D₂O at pD 14, 37°C, gave k = 0.00455 min^?1 (R² = 1.000) and τ_1/2 = 2.55 h; no hydrolysis product was observed over the course of the NMR experiment (4 h). It was concluded that ～13 h (5 half‐lives) of reaction time would yield a solution of aziridine which was relatively free of contaminants. Using these reaction conditions, ³H‐labeled chloroethylamines were used to synthesize 1‐(2‐chloro‐2‐[³H]‐ethyl)‐2‐[³H]‐aziridine and 2‐[³H]‐aziridine in situ. Copyright © 2007 John Wiley & Sons, Ltd.     

Coumarins Isolated from the Roots of Seseli resinosum. in Turkey

Abstract

Seseli resinosum. Freyn et Sint. (Umbelliferae) is a perennial herb that grows in the northern region of Anatolia, Turkey. The n.-hexane extract obtained from the roots of S. resinosum. was investigated for the presence of coumarins. Three angular-type pyranocoumarins and two linear-type furocoumarins were isolated from the roots. The compounds were identified as (+)-samidin [(3′S., 4′S.)-3′-senecioyloxy-4′-acetoxy-3′, 4′-dihydroseselin] (1), (?)-anomalin [(3′R., 4′R.)-3′, 4′-diangeloyloxy-3′, 4′-dihydroseselin] (2), calipteryxin (3′R., 4′R.)-3′-angeloyloxy-4′-senecioyloxy-3′, 4′-dihydroseselin (3), isoimperatorin (4), and deltoin (5). The structures were determined using spectroscopic methods (¹H NMR, ¹³C NMR, ¹H-¹H COSY, ¹H-¹³C COSY, HMBC, MS), physical methods (melting point and optical rotation), and chemical correlations with known compounds that have been described in the literature. The chemotaxonomic significance of these isolated coumarins is discussed in the genus Seseli. L.     

Evidence from binding studies for α2-adrenoceptors directly associated with glomeruli from rat kidney

Binding of the α₂-adrenoceptor radioligands [³H]clonidine and [³H]rauwolscine but not the α₁-adrenoceptor radioligand [³H]prazosin was enhanced in membranes prepared from rat isolated renal glomeruli. [³H]Rauwolscine binding to glomeruli was stereoselective with respect to the (−)-isomer of noradrenaline and the order of potency of a series of antagonists for displacement of binding indicated that the α₂-adrenoceptors in this preparation differ somewhat from those in some other species and tissues. Chemical sympathectomy produced no significant change in the number of sites labelled by [³H]rauwolscine indicating that few of the α₂-adrenoceptors in glomerular membranes are associated with sympathetic nerve terminals.     

用核磁共振新技术测定日本续断皂甙E1的结构

从日本续断Dipsocus japunicus Miq.根的乙醇提到物中得到一个新三萜皂甙(5糖甙)，命名为日本续断皂甙E₁(japondipsaponin E₁)。用化学方法及¹HNMR,¹³CNMR,¹H-¹H COSY，一维多重接力COSY，选择性远程DEPT和三重共振NOE差谱等方法，鉴定其结构为3-O-α-L-吡喃鼠李糖(1-3)-β-D-吡喃葡萄糖（1→3）-α-L-吡喃鼠李糖（1→2）-α-L-吡喃阿拉伯糖常春藤皂甙元28-O-β-D-吡喃葡萄糖甙。     

新疆雪莲化学成分的研究

从新疆雪莲的全草中分离得到一种新倍半萜内酯,根据红外光谱,核磁共振谱,质谱等证明了其结构式为1,并命名为雪莲内酯(Xuelianlactonc)。     

红果萝芙木季胺碱的化学研究

从红果萝芙木Rauvolfia verticillta(Lour.)Baill.f.rubrocarpa H.T.Chang.mss.根的水溶性碱部分,经盐析得到的生物碱,利用层析法。分得二个含量较高的生物碱,碱Ⅱ及碱Ⅵ。经光谱分析,化学反应和X射线衍射,证明碱Ⅵ为已知碱斯配加春(Ⅰ,spegatrine)。碱Ⅱ为一新生物碱,命名为维替新拉亭(Ⅱ,verticillatine)。药理研究表明斯配加春为α-肾上腺素能受体阻断剂,维替新拉亭则有神经节阻断作用。     

从远志中分离鉴定出一种多巴胺受体活性化合物

从中药远志中提出一种多巴胺受体的配基,四氢非州防己胺。此化合物在体外可抑制[³H]SCH23390和[³H]螺哌隆与大鼠纹状体膜的结合,IC₅₀值分别为0.75±0.08μmol·L^-1和0.92±0.10μmol·L^-1。它在体外还能抑制[³H]哌唑嗪和大鼠脑皮质细胞膜结合(IC₅₀值为46μmol·L^-1),但不能改变[³H]QNB及[³H]muscimol对膜的结合。Scatchandplot分析显示此化合物对[³H]SCH23390和[³H]螺哌隆与膜结合的抑制作用是通过竞争性与非竞争性混合机制而实现的。     

变色马兜铃中银袋内酯乙、丙的结构测定

从变色马兜铃(Aristolochia versicolar S M Hwang)的块根中分离到两个新倍半萜内酯,分别命名为银袋内酯乙(versicolactone B)和银袋内酯丙(versicolactone C)。前者分子式C₁₅H₂₀O₃,熔点135～136℃;后者分子式C₁₅H₂₂O₄,熔点181～182℃,[α]_D³⁶—11.4°(C,2.6,EtOH)。经光谱(UV,IR,¹H NMR,¹³SCNMR,MS)分析和化学方法证明,并经x-衍射证实,两者的结构分别为(Ⅰ)和(Ⅲ)。银袋内酯丙系一新型骨架的奠类倍半萜内酯。     

The Structure of Physalin T from Physalis alkekengi var. francheti

Abstract

A new steroidal constituent named physalin T (3) was isolated from the aqueous extract of Physalis alkekengi var. francheti. Based on ¹H and ¹³C NMR spectral studies the structure was assigned as 2,3-dihydrophysalin D, i.e., 5α,6β-dihydroxy-2,3,5,6-tetrahydrophysalin B, which is the first example of a natural physalin possessing a saturated ring A moiety. The structure was confirmed by the chemical transformation from the known physalin D (2) to physalin T.     

国产檀香中α-反式香柠烯醇化学结构研究

从国产檀香木Santalum ablum L.分得一个新倍半萜醇,根据光谱(IR,MS,¹H-¹H COSY,¹³C-¹H COSY和¹H-¹H NOESY)解析,确定了它的化学结构和相对立体化学为9(10)-顺,α-反式香柠烯醇[9(10)Z,α-trans-bergamotenol](Ia)。     

Coniothyren: a new phenoxyphenyl ether from the endophytic fungus,Coniothyrium sp.

Phytochemical investigation of the endophytic fungus Coniothyrium sp. resulted in the isolation of a new phenoxyphenyl ether, named coniothyren (1), and two known compounds, coniol (2) and (+)-epoxydon (3). The structure of the new compound was elucidated by detailed spectroscopic analysis, namely, ¹H NMR, ¹³C NMR, COSY, HMQC, HMBC, and HR-EI-MS. Preliminary studies demonstrated that (+)-epoxydon (3) displayed good antibacterial and antialgal activities toward Bacillus megaterium and Chlorella fusca, respectively.     

Growth and antioxidant response in <Emphasis Type="Italic">Hydrocharis dubis</Emphasis> (Bl.) Backer exposed to linear alkylbenzene sulfonate

A two-week exposure experiment was designed to investigate the toxicity of linear alkylbenzene sulfonate (LAS) on the aquatic plant Hydrocharis dubis (Bl.) Backer, focusing on growth, photosynthetic pigments and the activities of antioxidant enzymes. No significant differences were observed in the growth parameters of H. dubis when H. dubis was exposed to lower LAS doses (≤10 mg l⁻¹). However, lower LAS doses remarkably promote the dry weight accumulation of H. dubis. Higher doses of LAS (>10 mg l⁻¹) resulted in significant decreases in all growth parameters of H. dubis. No significant effect on pigment contents was observed at up to 50 mg l⁻¹ LAS, beyond which pigment contents declined gradually. Malondialdehyde (MDA) content did not show obvious differences when H. dubis plants were exposed to ≤50 mg l⁻¹ LAS. Peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) activities showed a concentration-dependent increase up to LAS concentrations of 0.1–10 mg l⁻¹, followed by a clear decrease. The results of this study suggest that LAS significantly inhibited the growth and physiology of H. dubis when the dose of LAS exceeded 10 mg l⁻¹ . Therefore, LAS at current environmental concentrations dose not appear to cause evident phytotoxic effects on H. dubis.