ent-Kaurenoids from the roots of Cacalia pilgeriana

Two new ent-kaurenoids,19-acetoxyl-ent-3beta,17-dihydroxykaur-15-ene (1), 19-acetoxyl-ent-3beta-hydroxykaur-15-en-17-al (2), together with seven known ent-kaurenoids: ent-kaur-16-en-19-al (3), ent-kaur-16-en-19-oic acid (4), ent-kauran-16beta,17-diol (5), ent-15beta, 16beta-epoxy-17-hydroxykauran-19-oic acid (6),19-acetyl-ent-3beta-hydroxyl-kaur-16-ene (7), ent-3beta,19-dihydroxykaur-16-ene (8), ent-17-hydroxykaur-15-ene (9), were isolated from Cacalia pilgeriana. Their structures were elucidated by spectroscopic methods including 2D NMR spectral analysis.     

Cytotoxic diterpenoids from the roots of Euphorbia ebracteolata

Three new diterpenoids, yuexiandajisu D (1), E (2) and F were isolated from the roots of Euphorbia ebracteolata, along with eight known diterpenoids, jolkinolide B (4), jolkinolide A, ent-11alpha-hydroxyabieta-8(14),13(15)-dien-16,12alpha-olide (6), ent-(13S)-hydroxyatis-16-ene-3,14-dione, ent-3beta,(13S)-dihydroxyatis-16-en-14-one, ent-3-oxokaurane-16alpha,17-diol, ent-16alpha,17-dihydroxyatisan-3-one and ent-atisane-3beta,16alpha,17-triol. The structures of all compounds were deduced using spectroscopic methods and confirmed for 1 and 2 by single-crystal X-ray diffraction. A biogenetic pathway for the formation of 1 and 2 is proposed briefly. Cytotoxic activities were evaluated against ANA-1, B 16 and Jurkat tumor cells. Jolkinolide B (4) displayed modest activity on ANA-1, B 16 and Jurkat tumor cells with IC50 values 4.46 x 10(-2), 4.48 x 10(-2), 6.47 x 10(-2) microM, and ent-11alpha-hydroxyabieta-8(14),13(15)-dien-16,12alpha-olide (6) showed significant activity against ANA-1 and Jurkat cells with IC50 values 7.12 x 10(-3) and 1.79 x 10(-2) microM. Compound 1 was found to be slightly active against ANA-1 cells with an IC50 value 2.88 x 10(-1)microM. Structure-activity relationships of isolated compounds are also discussed.     

Synthesis and antiviral activity of the enantiomeric forms of carba-5-iodo-2'-deoxyuridine and carba-(E)-5-(2-bromovinyl)-2'-deoxyuridine

Both enantiomers of the carbocyclic analogues of 5-iodo-2'-deoxyuridine (14 and ent-14) and of (E)-5-(2-bromo-vinyl)-2'-deoxyuridine (16 and ent-16) were synthesized by using (+)- or (-)-endo-norborn-5-en-2-yl acetate or butyrate, respectively, as starting materials. Against herpes simplex virus type 1 (+)-C-BVDU (16) was only slightly less active than BVDU itself, whereas (-)-C-BVDU (ent-16) proved to be 10-400-fold less effective, depending on the strain investigated. Against HSV-2 both (+)- and (-)-C-BVDU as well as (+)- and (-)-C-IDU showed minor activity. All carbocyclic analogues were inactive against TK-HSV-1 strains, pointing to the prerequisite of phosphorylation (activation) by the viral thymidine kinase (TK).     

New macrocyclic lathyrane diterpenes, from Euphorbia lagascae, as inhibitors of multidrug resistance of tumour cells

The new macrocyclic lathyrane diterpenes latilagascenes A and B ( 1 and 2), the diacetylated derivative of 2, latilagascene C ( 3), and the known diterpenes ent-16alpha,17-dihydroxyatisan-3-one ( 4) and ent-16alpha,17-dihydroxykauran-3-one ( 5), isolated from the methanol extract of Euphorbia lagascae, were examined for their effects on the reversal of multidrug resistance (MDR) on mouse lymphoma cells. Among the active lathyrane derivatives 1 - 3, compound 2 displayed the highest inhibition of rhodamine 123 efflux of human MDR1 gene transfected mouse lymphoma cells when compared to the untreated cells or the positive control verapamil. The new compounds are the first macrocyclic lathyrane diterpenes showing oxidation at C-16, whose structures were characterized by extensive spectroscopic methods, including 2D NMR experiments ( (1)H- (1)H COSY, HMQC, HMBC and NOESY). The known phenolic compounds vanillic acid ( 6), p-salicylic acid ( 7), isofraxidin ( 8) and cleomiscosin A ( 9) were also isolated from this species.     

New constituents of Leontopodium alpinum and their in vitro leukotriene biosynthesis inhibitory activity

Phytochemical investigations of the roots of Leontopodium alpinum Cass. resulted in the isolation and structure elucidation of six novel compounds and two known compounds. Novel constituents could be identified as the polyacetylenes 1-acetoxy-3-angeloyloxy-(4 E,6 E)-tetradeca-4,6-diene-8,10,12-triyne and its (6 Z)-isomer, the kaurenic acid derivative methyl ent-7alpha,9alpha-dihydroxy-15beta-[(2 Z)-2-methyl-but-2-enoyloxy]kaur-16-en-19-oate, the bisabolane derivative (1 R*,3 S*,4 R*,6 S*)-9-(acetoxy)-4-hydroxy-1-[(2Z)-2-methylbut-2-enoyloxy]bisabol-10(11)-ene and the lignans [(2 S,3 R,4 R)-4-(3,4-dimethoxybenzyl)-2-(3,4,5-trimethoxyphenyl)-tetrahydrofuran-3-yl]-methyl-(2 Z)-2-methylbut-2-enoate and its 3,4,5-trimethoxybenzyl derivative. Known compounds, reported here for the first time for the genus Leontopodium, were identified as ent-kaur-16-en-19-oic acid and T-cadinol. The obtained compounds were tested together with 15 previously described compounds of L. alpinum in an ex vivo leukotriene biosynthesis inhibition assay. The highest activities were determined for the bisabolane derivates (IC50: 7.7 to 11.4 microM), one lignan (IC50: 10.7 microM) and the ent-kaurenoate (IC50: 10.4 microM).     

Cyclopropane-based conformational restriction of histamine. (1S,2S)-2-(2-aminoethyl)-1-(1H-imidazol-4-yl)cyclopropane,a highly selective agonist for the histamine H3 receptor,having a cis-cyclopropane structure

A series of cyclopropane-based conformationally restricted analogues of histamine, the "folded" cis-analogues, i.e., (1S,2R)-2-(aminomethyl)-1-(1H-imidazol-4-yl)cyclopropane (11), (1S,2S)-2-(2-aminoethyl)-1-(1H-imidazol-4-yl)cyclopropane (13), and their enantiomers ent-11 and ent-13, and the "extended" trans-analogues, i.e., (1R,2R)-2-(aminomethyl)-1-(1H-imidazol-4-yl)cyclopropane (12) and its enantiomer ent-12, were designed as histamine H(3) receptor agonists. These target compounds were synthesized from the versatile chiral cyclopropane units, (1S,2R)- and (1R,2R)-2-(tert-butyldiphenylsilyloxy)methyl-1-formylcyclopropane (14 and 15, respectively) or their enantiomers ent-14 and ent-15. Among the conformationally restricted analogues, the "folded" analogue 13 (AEIC) having the cis-cyclopropane structure was identified as a potent H(3) receptor agonist, which showed a significant binding affinity (K(i) = 1.31 +/- 0.16 nM) and had an agonist effect (EC(50) value of 10 +/- 3 nM) on the receptor. This compound owes its importance to being the first highly selective H(3) receptor agonist to have virtually no effect on the H(4) subtype receptor. These studies showed that the cis-cyclopropane structure is very effective in the conformational restriction of histamine to improve the specific binding to the histamine H(3) receptor.     

豨莶脂溶性成分的研究

从豨莶(Siegesbeckia orientalis L.)的地上部分,分离出八个化合物,其中I和I根据理化性质和光谱数据确定其结构为ent-17-acetoxy-18-isobutyryloxy-16(α)-kauran-19-oicacid(I)和ent-17-ethoxy-16(α)-kauran-19-oicacid(II),均为新化合物,分别被命为豨莶酯酸(siegesesteric acid,I)和豨莶醚酸(siegesetheric acid,I)。其余化合物分别鉴定为腺梗豨莶萜醇酸(ent-16β,17-dihydroxy-kauran-19-oicacid,II),奇任醇(kirenol,IV,β-谷甾醇葡萄糖甙(β-sitosterolglucoside,V),二十一醇(heneicosanol,VI),花生酸甲酯(methyl arachidate,VII)和β-谷甾醇(β-sitosterol,VII)。除奇任醇和β-谷甾醇外,均为首次从该植物中分得。     

Hydroxylation and glucosidation of ent-16beta-Hydroxybeyeran-19-oic acid by Bacillus megaterium and Aspergillus niger

ent-16beta-Hydroxybeyeran-19-oic acid ( 1) has potential antihypertensive activity. To obtain novel and more-effective compounds, 1 was incubated with Bacillus megaterium ATCC 14 581 and Aspergillus niger CCRC 32 720. The structures of the metabolites were determined by HR-FAB-MS, 1D- and 2D-NMR spectral data, and enzymatic hydrolysis. Bacillus megaterium hydroxylated and glucosidated 1 to yield ent-7alpha,16beta-dihydroxybeyeran-19-oic acid ( 2), ent-16beta-hydroxybeyeran-19-oic acid alpha- D-glucopyranosyl ester ( 3), and ent-7alpha,16beta-dihydroxybeyeran-19-oic acid alpha- D-glucopyranosyl ester ( 4). Aspergillus niger hydroxylated 1 to yield ent-1beta,7alpha,16beta-trihydroxybeyeran-19-oic acid ( 5) and ent-1beta,7alpha-dihydroxy-16-oxobeyeran-19-oic acid ( 6). Metabolites 3 - 5 were characterized as new compounds. In addition, 2, 3, 5, and 6 were tested for antihypertensive effects, and we found that 5 and 6 were more potent than the parent compound 1.     

Chemical constituents of Nouelia insignis Franch

Two new diterpenes and ent-15alpha-hydroxykaur-16-en-19-oic acid 11,12-acetonide (3), together with 23 known compounds were isolated from the dried aerial parts of Nouelia insignis Franch. The structures of new compounds were determined to be ent-14beta,15alpha-dihydroxykaur-16-en-19-oic acid (1), ent-14beta-hydroxy-15-oxokaur-16-en-19-oic acid (2) on the basis of spectral and chemical evidence. The structure of ent-11alpha,16alpha-epoxy-15alpha-hydroxy-16S-kaur-19-oic acid (4) was confirmed by X-ray crystallographic analysis.     

Three new pimaren diterpenoids from marine mangrove plant, Bruguiera gymnorrhiza

Three new pimaren diterpenoids, ent-8(14)-pimarene-15R, 16-diol (1), ent-8(14)-pimarene-1alpha,15R,16-triol (2), and (5R, 9S, 10R, 13S, 15S)-ent-8(14)-pimarene-1-oxo-15R,16-diol (3), along with three known diterpenoids (4-6) have been isolated from the stem of mangrove plant Bruguiera gymnorrhiza. The structures of compounds 1-3 were determined by extensive spectroscopic (2D NMR, MS, IR, and CD) analysis, and 3 and 5 showed moderate cytotoxic activities against L-929 and K562, respectively.     

山莓中两个新二萜的分离与鉴定

为研究山莓(Rubus corchorifolius L.f)的化学成分，应用硅胶柱色谱进行分离纯化，根据化合物的理化性质和波谱数据鉴定结构。本文分离鉴定了2个贝壳杉烷二萜化合物，其结构分别为对映-贝壳杉烷-3α，16α，17，19-四醇(1)，对映-2-羰基-16α-羟基-贝壳杉烷-17-β-D-葡糖苷(2)。化合物1、2均为新化合物。     

神经肌肉阻滞剂罗库溴铵有关物质D的制备

目的合成1-[3α-乙酰氧基-17β-羟基-2β-(吗啡啉-4-基)-5α-雄甾烷-16β-基]-1-(丙烯-2-基)四氢吡咯鎓溴化物(有关物质D)。方法以2α,3α,16α,17α-二环氧-17-乙酰氧基-5-雄甾烷为起始原料,经吡咯烷开环、硼氢化钠还原、开环反应、酰化反应等反应,经柱层析分离纯化拆分了三种光学异构体,合成(2β,3α,5α,16α,17β)-2-(4-吗啉)-16-(1-吡咯基)-雄甾-3,17-二醇3-乙酸酯,然后经催化和烯丙基溴反应合成了有关物质1-[3α-乙酰氧基-17β-羟基-2β-(吗啡啉-4-基)-5α-雄甾烷-16β-基]-1-(丙烯-2-基)四氢吡咯鎓溴化物(有关物质D)。结果其结构经1H-NMR和LC-MS证实。结论该合成方法能够合成罗库溴铵有关物质D,为控制产品质量提供有关物质对照品。     

Novel ent-Beyeran-19-oic acids from biotransformations of isosteviol metabolites by Mortierella isabellina

Biotransformations of ENT-16beta-hydroxybeyeran-19-oic acid ( 1) by Mortierella isabellina produced hydroxylated metabolites. The isolated metabolites included three new compounds, ent-14beta,16beta-dihydroxybeyeran-19-oic acid ( 3), ent-12beta-hydroxy-16-oxobeyeran-19-oic acid ( 4), and ent-7alpha,12beta-dihydroxy-16-oxobeyeran-19-oic acid ( 5), and one known compound, ent-7alpha,16beta-dihydroxybeyeran-19-oic acid ( 2). The structural elucidation was achieved by detailed analysis of LC-MS chromatograms, and MS and NMR spectroscopic data. In this study, M. isabellina hydroxylated the basic skeleton beyeran-19-oic acid at the 7beta-, 12alpha-, and 14alpha-positions, and oxidized the skeleton at the 16-position. All compounds were evaluated with the cell viability assay. The results of the bioassay indicated that MTT formazan exocytosis occurs upon treatment of the cells with 1.     

Two new diterpenoid dimers,fritillebinide D and E,from bulbs of Fritillaria ebeiensis

Two new ent-kaurane diterpenoid dimers, fritillebinide D (1) and fritillebinide E (2), were isolated from bulbs of Fritillaria ebeiensis G.D. Yu et G.Q. Ji. Their structures have been determined to be ent-3β-acetoxy-kauran-16β, 17-acetal ent-3β-acetoxy-16β-kauran-17(R)-aldehyde (1) and ent-3β-acetoxy-kauran-16β,17-acetal ent-3β-acetoxy-16β-kauran-17(S)-aldehyde (2) by means of spectral analysis.     

彭泽贝母中二萜类成分

为了研究彭泽贝母的化学成分。利用多种柱色谱方法进行分离纯化，根据光谱数据和理化性质进行结构鉴定。共分离并鉴定了6个对映-贝壳杉类二萜化合物： ent-kauran-15-en-17-ol (I)， ent--kauran-15-en-3α,17-diol (II)， 鄂贝新醇(III)， ent--kauran-16α,17-diol (IV)， ent--kauran-3α，16α,17-triol (V)， ent--16,17-epoxy-kauran-3α-ol (VI)。6个化合物均为首次从彭泽贝母中分得，其中ent--16,17-epoxy-kauran-3α-ol (VI)为新化合物。     

Synthesis of bicyclic sigma receptor ligands with cytotoxic activity

All possible stereoisomeric alcohols (6-benzyl-8-(4-methoxybenzyl)-6,8-diazabicyclo[3.2.2]nonan-2-ol) and methyl ethers (6-benzyl-2-methoxy-8-(4-methoxybenzyl)-6,8-diazabicyclo[3.2.2]nonane) are prepared from (R)- and (S)-glutamate. A Dieckmann analogous cyclization, which makes use of trapping the primary cyclization product with Me3SiCl, generates the bicyclic framework. Stereoselective LiBH4 reduction and Mitsunobu inversion establish the configuration in position 2. Enantiomeric alcohols 15 (1S,2S,5R) and ent-15 (1R,2R,5S) as well as diastereomeric methyl ethers ent-17 (1R,2R,5S) and ent-22 (1R,2S,5S) display high sigma1 receptor affinity. Cell growth inhibition of the stereoisomeric alcohols and methyl ethers against five human tumor cell lines is investigated. In particular, at a concentration of 20 muM the four methyl ethers stop completely the cell growth of the small cell lung cancer cell line A-427, indicating a specific target in this cell line. The IC50-values of methyl ethers ent-17 and ent-22 are in the range of the antitumor drugs cisplatin and oxaliplatin. Binding assays show that the investigated tumor cell lines express considerable amounts of sigma1 and sigma2 receptors.     

Characterization of Three Labdane Diterpenes from Aframomum alboviolaceum

Two labdane diterpenes were isolated from the seeds and the rhizomes of AFRAMOMUM ALBOVIOLACEUM (Ridley) K. Schum (Zingiberaceae) and identified by GC-MS, (1)H-, and (13)C-NMR as ( E)-labda-8(17),12-diene-15,16-dial ( 1) and ( E)beta,17-epoxy-labd-12-ene-15,16-dial ( 2). A third minor compound could be the methyl ( E)-14xi,15-epoxylabd-8(17),12-dien-16-oate. The simultaneous occurrence of these three molecules has been mentioned only in one other species of the same genus, AFRAMOMUM DANIELLII (1).     

Diterpenoids from the Chinese herb Caryopteris terniflora and their antibacterial and antitumor activity

Two ent-kaurene type diterpenoids, diterpenoids A (1) and B (2) were isolated from the Chinese herb Caryopteris terniflora and defined as ent-7beta, 11alpha,14-trihydroxy-18-aldehyde-11beta-20-epoxy-kaur-16-en15-one and ent-7beta,14-dihydroxy-11alpha-methoxy-18-aldehyde-11beta-20-epoxy-kaur-16-en-15-one respectively. Compounds 1 and 2 showed significant antibacterial and antitumour activity.     

Synthesis, characterization, and receptor interaction profiles of enantiomeric bile acids

Bile acids are endogenous steroid detergents with receptor-mediated physiologic actions including activation of the G-protein coupled receptor TGR5 and gene regulation mediated by nuclear receptors. In this study, we report the first synthesis of enantiomeric lithocholic acid (ent-LCA, ent-1) and chenodeoxycholic acid (ent-CDCA, ent-2) via ent-testosterone (3). ent-1 was synthesized in 21 total steps in 4.2% yield, whereas ent-2 was obtained in 23 total steps in 0.8% yield. Critical micelle concentrations of the enantiomeric bile acids were found to be identical to their natural counterparts. Furthermore, enantiomeric bile acids were also tested for their ability to modulate bile acid activated proteins: farnesoid X receptor, vitamin D receptor, pregnane X receptor, and TGR5. Interestingly, ent-1 and ent-2 showed differential interactions with these proteins as compared to their corresponding natural bile acids. These data highlight the potential for using enantioselectivity as a way to distinguish between receptor and nonreceptor-mediated functions of natural bile acids.     

安徽贝母中的新二萜成分

为了研究安徽贝母(Fritillaria anhuiensis S.C.Chen et S.E.Yin)的化学成分。将安徽贝母的干燥鳞茎用95%乙醇回流提取后，用硅胶柱色谱进行分离纯化，得到了3个化合物。根据化合物的理化性质和光谱数据进行结构鉴定，分别为12,15-epoxy-8(17),13-labdadien-19-ol (1)，ent-3β-acetoxy-kauran-16β,17-diol (2)，ent-kaurane-3β,16β,17-triol (3)。化合物1为新的labdane型二萜类化合物，化合物2和3为首次从该植物中得到。