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1.
We found that Acremonium strictum NN106 converted 4-androstene-3, 17-dione (androstenedione) to 12 compounds. Among them, five products were isolated and found to be hydroxylated at the 11α-, 14α-, 7α, 11α-, 6β, 11α- or 6β, 14α-positions of androstenedione. 6β, 11α-Dihydroxy and 6β, 14α-dihydroxy derivatives of androstenedione have been obtained for the first time. From the time course profile of this transformation, sequential hydroxylation at the 6β-position followed by 11α- or 14α-monohydroxylation was observed. The oxidative product of the 6β, 14α-dihydroxy derivative was found to be the most potent inhibitor of human placentral aromatase.  相似文献   

2.
《Phytochemistry》1987,26(9):2585-2587
In addition to five known sesquiterpenoids, six new compounds were isolated from Smyrnium perfoliatum. The new compounds were 1β-acetoxy-eudesma-3,7(11),8-trien-8,12-olide, 1β-acetoxyeudesma-4(15),7(11),8-trien-8,12-olide, 1β-10α;4α,5β-diepoxy-8β-isobutoxy-glechomanolide, 1β, 10α;4α,5β-diepoxy-8α-isobutoxy-glechomanolide, 1β,4α-dihydroxy-2α,3α-epoxy-eudesma-7(11),8-dien-8,12-olide, 1β,4α-dihydroxy-2α,3α-epoxy-8β-methoxy-eudesma-7(11)-en-8α,12-olide.  相似文献   

3.
Two new eudesmane sesquiterpenoids were isolated from the fruits of Daucus carota L. The structures were established based on the interpretation of high-resolution MS and 1D- and 2D-NMR data, the absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. The new compounds were elucidated as (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β, 11-tetrahydroxy decahydronaphthalene (1) and (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β-trihydroxy decahydronaphthalene-11-O-β-d-glucopyranoside (2). The compound 1 showed significant antioxidant activity.  相似文献   

4.
The syndrome of 17α-hydroxylase deficiency is due to the inability to synthesize cortisol and is associated with enhanced secretion of both corticosterone and 11-deoxy-corticosterone (DOC). In humans, corticosterone and its 5α-Ring A-reduced metabolites are excreted via the bile into the intestine and transformed by anaerobic bacteria to 21-dehydroxylated products: 11β-OH-progesterone or 11β-OH-(allo)-5α-preganolones (potent inhibitors of 11β-HSD2 and 11β-HSD1 dehydrogenase). Neomycin blocks the formation of these steroid metabolites and can blunt the hypertension in rats induced by either ACTH or corticosterone. 3α,5α-Tetrahydro-corticosterone, 11β-hydroxy-progesterone, and 3α,5α-tetrahydro-11β-hydroxy-progesterone strongly inhibit 11β-HSD2 and 11β-HSD1 dehydrogenase activity; all these compounds are hypertensinogenic when infused in adrenally intact rats.Urine obtained from a patient with 17α-hydroxylase deficiency demonstrated markedly elevated levels of endogenous glycyrrhetinic acid-like factors (GALFs) that inhibit 11β-HSD2 and 11β-HSD1 dehydrogenase activity (>300 times greater, and >400 times greater, respectively, than those in normotensive controls). Thus, in addition to DOC, corticosterone and its 5α-pathway products as well as the 11-oxygenated progesterone derivatives may play a previously unrecognized role in the increased Na+ retention and BP associated with patients with 17α-hydroxylase deficiency.  相似文献   

5.
Bioassay-guided fractionation of an 80% MeOH extract of Juglan sinensis leaves and twigs has resulted in the isolation of three new triterpenes (1-3) and two new sesquiterpenes (4-5) along with two known sesquiterpenes (6-7). The new compounds were determined to be 3β, 11α, 19α, 24, 30-pentahydroxy-20β, 28-epoxy-28β-methoxy-ursane (1), 1α, 3β-dihydroxy-olean-18-ene (2), 2α, 3α, 23-trihydroxy-urs-12-en-28-oic acid 28-O-β-d-glucopyranoside (3), (4S, 5S, 7R, 8R, 14R)-8, 11-dihydroxy-2, 4-cyclo-eudesmane (4), 15-hydroxy-α-eudesmol-11-O-β-d-glucopyranoside (5), by spectroscopic analysis. The cytotoxicity of compounds (1-7) against four cancer cell lines such as B16F10, Hep-2, MCF-7 and U87-MG was evaluated. Compounds 1, 2, 6 and 7 showed potent cytotoxicity against all of four cancer cell lines, respectively.  相似文献   

6.
有些种子植物如莎草科、十字花科、灯心草科、藜科、石竹科等20余科,以往曾被认为不能或不易形成丛枝菌根(郭秀珍等,1989;刘润进等,2000).随着对菌根的深入研究,曾被认为是不易与菌根菌组合的湿地生植物、寄生性植物、或一年生植物都被发现是可以形成内生菌根的(Trappe等,1992).此外,Allen等(1989)研究证实,Salsola kali,Atriplex roseum等生长于沙漠、海滨的藜科植物,进行接种处理后,也能形成丛枝菌根.我们在西双版纳调查热带雨林植物的丛枝菌根状况时,偶然发现刺苋(Amaranthus spinosus Linn.)的根系受到了丛枝菌根真菌的侵染,因此,对苋科植物作了扩大采样调查.本文主要报道从热带采集的5属6种苋科植物的根受丛枝菌根真菌感染形成丛枝菌根(arbuscular mycorrhiza,AM)和这些植物根际士壤中的丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)的状况.  相似文献   

7.
从肋果茶(Sladenia celastrifolia)95%乙醇提取物的乙酸乙酯部位中分离得到15个萜类化合物,经波谱学方法分别鉴定为sladeniafolin A(1),grasshopper ketone (2),(3S,5R,6S,7E,9R) -7-megastigmene-3,6,9-triol (3),hedytriol (4),(3S,5R,6R,7E,9R) -3,5,6,9-tetrahydroxy-7-megastigmene(5),1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′-trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien -2-one (6),2α,3α,19α,23-tetrahydroxyurs-12-en-28-oic acid (7),2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid(8),pomolic acid(9),3-O-acetyl pomolic acid(10),ursaldehyde (11),camarolide (12),3β-hydroxyurs-11-en-13β(28) -olide (13),3β-hydroxy -11α,12α-epoxy-urs-13β,28-olide (14)和28-0-β-D-glucopyranosyl euscaphic acid (15).以上化合物均首次从该植物中分离得到,其中1为新的C9裂环烯醚萜.  相似文献   

8.
Two hundred thirteen cytochrome P450 (P450) genes were collected from bacteria and expressed based on an Escherichia coli expression system to test their hydroxylation ability to testosterone. Twenty-four P450s stereoselectively monohydroxylated testosterone at the 2α-, 2β-, 6β-, 7β-, 11β-, 12β-, 15β-, 16α-, and 17-positions (17-hydroxylation yields 17-ketoproduct). The hydroxylation site usage of the P450s is not the same as that of human P450s, while the 2α-, 2β-, 6β-, 11β-, 15β-, 16α-, and 17-hydroxylation are reactions common to both human and bacterial P450s. Most of the testosterone hydroxylation catalyzed by bacterial P450s is on the β face.  相似文献   

9.
20-Oxo-5β-[9,12,12-(2)H(3)]pregnan-3α-yl-l-glutamyl 1-ester 11 was synthesized as an internal standard for quantification of a neuroprotective NMDA receptor ligand, 20-oxo-5β-pregnan-3α-yl-l-glutamyl 1-ester 18 and its metabolites, in plasma and tissue. 11α-Hydroxy-progesterone (1) was reduced under basic conditions to yield the corresponding 5β-steroid. Protection of the 3- and 20-oxo groups and oxidation of the 11α-hydroxy group was then followed by a deuterium exchange, conducted under basic conditions using deuterated methanol. Next, the carbonyl moiety at C-11 was reduced and the 11α-hydroxyl group removed through utilization of the Barton-McCombie reaction. Subsequent deprotection of the 3- and 20-acetals and stereoselective reduction of the 3-oxo group gave the desired trideuterated pregnanolone (8). This was coupled with protected glutamic acid, which was then deprotected to yield [9,12,12-(2)H(3)]-pregnanolone glutamate (11) with >99% isotopic purity.  相似文献   

10.
The known compounds chrysoeriol, apigenin, luteolin, acacetin, scutellarein, 6-methoxyluteolin, apigenin 7-glucoside, luteolin 7-glucoside, esculetin, chrysophanol, asphodeline, mircocarpin, sitosterol, 1-β-acetoxyeudesman-4(15),7(11)dien-2α,12-olide and 1-β-acetoxy-8β-hydroxyeudesman-4(15),7(11)-dien-8α,12-olide were isolated from Asphodeline globifera and A. damascena. A new sesquiterpene lactone 1-β-acetoxy-8β-ethoxyeudesman-4(15),7(11)dien-8α, 12-olide was also characterized. These are the first reports of sesquiterpene lactones in Asphodeline and in the Liliaceae.  相似文献   

11.
In obesity, rapidly expanding adipose tissue becomes hypoxic, precipitating inflammation, fibrosis, and insulin resistance. Compensatory angiogenesis may prevent these events. Mice lacking the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1(-/-)) have "healthier" adipose tissue distribution and resist metabolic disease with diet-induced obesity. Here we show that adipose tissues of 11βHSD1(-/-) mice exhibit attenuated hypoxia, induction of hypoxia-inducible factor (HIF-1α) activation of the TGF-β/Smad3/α-smooth muscle actin (α-SMA) signaling pathway, and fibrogenesis despite similar fat accretion with diet-induced obesity. Moreover, augmented 11βHSD1(-/-) adipose tissue angiogenesis is associated with enhanced peroxisome proliferator-activated receptor γ (PPARγ)-inducible expression of the potent angiogenic factors VEGF-A, apelin, and angiopoietin-like protein 4. Improved adipose angiogenesis and reduced fibrosis provide a novel mechanism whereby suppression of intracellular glucocorticoid regeneration promotes safer fat expansion with weight gain.  相似文献   

12.
Beauveria bassiana KCH 1065, as was recently demonstrated, is unusual amongst fungal biocatalysts in that it converts C19 3-oxo-4-ene and 3β-hydroxy-5-ene as well as 3β-hydroxy-5α-saturated steroids to 11α-hydroxy ring-D lactones. The Baeyer–Villiger monooxygenase (BVMO) of this strain is distinguished from other enzymes catalyzing BVO of steroidal ketones by the fact that it oxidizes solely substrates with 11α-hydroxyl group. The current study using a series of 5α-saturated steroids (androsterone, 3α-androstanediol and androstanedione) has highlighted that a small change of the steroid structure can result in significant differences of the metabolic fate. It was found that the 3α-stereochemistry of hydroxyl group restricted “normal” binding orientation of the substrate within 11α-hydroxylase and, as a result, androsterone and 3α-androstanediol were converted into a mixture of 7β-, 11α- and 7α-hydroxy derivatives. Hydroxylation of androstanedione occurred only at the 11α-position, indicating that the 3-oxo group limits the alternative binding orientation of the substrate within the hydroxylase. Only androstanedione and 3α-androstanediol were metabolized to hydroxylactones. The study uniquely demonstrated preference for oxidation of equatorial (11α-, 7β-) hydroxyketones by BVMO from B. bassiana. The time course experiments suggested that the activity of 17β-HSD is a factor determining the amount of produced ring-D lactones. The obtained 11α-hydroxylactones underwent further transformations (oxy-red reactions) at C-3. During conversion of androstanedione, a minor dehydrogenation pathway was observed with generation of 11α,17β-dihydroxy-5α-androst-1-en-3-one. The introduction of C1C2 double bond has been recorded in B. bassiana for the first time.  相似文献   

13.
中华青荚叶的一个新果糖酯   总被引:1,自引:0,他引:1  
从山茱萸科中华青荚叶( Helwingia chinensis )的乙醇提取物中分离得到一个新果糖酯和十个已知化合物.通过现代波谱技术分别鉴定为:2- O -(E)-咖啡酰-3- O -(3, 5-二甲氧基香豆酰)-α-D-呋喃果糖甙(1),2- O -β-D-呋喃果糖基α-D-异吡喃糖酯(2),甘草甜素(3),4′-羟基-7- O -葡萄糖-2, 3-二羟黄酮甙(4),黄豆甙(5),5-葡萄糖芹菜甙(6),7- O -葡萄糖芹菜甙(7),4- O -葡萄糖香豆酸(8), 葡萄糖咖啡酸(9), 3β-赤杨醇(10), 薯蓣皂甙3- O -{α-L-鼠李糖吡喃糖基(1→2)-[α-L-阿拉伯呋喃糖基(1→3)]-β-D-葡萄糖吡喃糖} (11).  相似文献   

14.
黑虎掌 (Sarcodonaspratum (Berk .)S .Ito) ,又名香茸 ,是一种美味食用菌。近年来发现该属S .scabro sus (Fr.)P .Karst.中含有对神经生长因子 (NGF)的合成具有诱导作用的生物活性二萜 (Oht等 ,1998)。作为“高等真菌生物活性代谢产物研究”的一部分 ,我们对采自云南武定的样品进行了化学分析。从黑虎掌的新鲜子实体中分得 15个化合物。它们分别为cerebrosideB (1) (12 0mg) ,阿洛酮糖腺苷(2 ) (12mg) ,三磷酸尿苷 (3) (7mg) ,尿嘧啶 (4 ) (12mg) ,腺嘌呤 (5 ) (8m…  相似文献   

15.
Two new sesqulterpenoid glucosides, namely α-hydroxycostic acid 6-β-D-glucopyranoside (compound 1) and 11 βH-11,13-dlhydrodehydrocostuslactone 8α-O-(6'-acetyl)-β-D-glucopyranoside (compound 2), along with 11 known sesqulterpenoids (compounds 3-13) were isolated from the aerial parts of Saussurea involucrate (Kar. et Kir.) Sch.- BIp. The structures of the new sesquiterpenoid glucosides were established by one- and two-dimensional nuclear magnetic resonance and mass spectrometry analysis.  相似文献   

16.
Allium inutile Makino in Bot.Mag.Tokyo 12:104.1898.- Nothoscordum inutile(Makino)kitamura in Bot.Mag.Tokyo 59:35.1946.  相似文献   

17.
Seven compounds have been isolaed from the roots of Curculigo orchioides. On the basis of spectral analysis,their structures were elucidated as 2,6-dimethoxy benzoic acid (A),orcinol glucopyranoside(B),curculigine A(C),curculigoside(D),24s,3β,11α,16,24-tetrahyaroxycycloartenol-3-O-α-L-rhamnopyranosyl(1→2)-β-D-glucopyranoside(E),24s,3β,11a,16β,24-tetrahydroxycycloartenol-3-O-β-d-glucopyranosyl(1→2)-β-D-glucopyranoside(F) and dancosterol(G). Saponin F is a new tritepenoid compound.  相似文献   

18.
利用本研究室已构建的重组菌Bacillus subtilis/pBSMuL3-α/β-CGTase对产B.stearothermophilus环糊精葡萄糖基转移酶的发酵产酶进行了优化,考察了培养基中重要成分:碳源、有机氮源、无机氮源、有机与无机氮源质量比、碳源与氮质量比、金属离子种类等单因素对该重组菌产α/β-CGTase的影响,并采用正交实验对发酵培养基进行优化,对优化结果分析可知,重组菌B.subtilis/pBSMuL3-α/β-CGTase发酵产α/β-CGTase的最优培养基成本为:葡萄糖5 g/L,氮源(鱼骨蛋白胨∶NH4Cl=3∶1)25 g/L,1 mmol/L Mg^2+。在最优条件下发酵培养,α/β-CGTase的酶活由原来TB发酵培养基的9.20 U/mL提高至20.32 U/mL,是优化前酶活的2.2倍,为α/β-环糊精葡萄糖基转移酶的工业应用提供了理论支持。  相似文献   

19.
This study reports the synthesis of several new steroidal lactones: 5α,6β-dibromo-17a-oxa-D-homoandrostane-3β-yl-3'-oxapentanoate (11), 5α,6β-dibromo-17a-oxa-D-homoandrostane-3β-yl-propanoate (12), 5α,6β-dibromo-17a-oxa-D-homoandrostane-3β-yl-butanoate (13), 5α,6β-dibromo-17a-oxa-D-homoandrostane-3β-yl-pentanoate (14), 5α,6β-dibromo-17a-oxa-D-homoandrostane-3β-yl-hexanoate (15), 17a-oxa-D-homoandrost-5-en-17-one-3β-yl-3'-oxapentanoate (16), 17a-oxa-D-homoandrost-5-en-17-one-3β-yl-propanoate (17), 17a-oxa-D-homoandrost-5-en-17-one-3β-yl-butanoate (18), 17a-oxa-D-homoandrost-5-en-17-one-3β-yl-pentanoate (19) and 17a-oxa-D-homoandrost-5-en-17-one-3β-yl-hexanoate (20) with a therapeutic potential as antiandrogens. The biological effect of these steroids was demonstrated in in vivo as well as in vitro experiments. In the in vivo experiments, we measured the activity of ten new steroidal derivatives on the weight of the prostate and seminal vesicle glands of gonadectomized hamsters treated with testosterone. For the in vitro studies, we determined the IC(50) values by measuring the concentration of the steroidal derivatives that inhibits 50% of the activity of the 5α-reductase enzyme present in human prostate and also its binding capacity to the androgen receptors (AR) obtained from rat's prostate cytosol. The results from these experiments indicated that compounds 11-20, significantly decreased the weight of the prostate and seminal vesicles as compared to testosterone treated animals; this reduction of the weight of these glands was comparable to that produced by Finasteride. On the other hand, compounds 11-20 inhibited the enzyme 5α-reductase, with compounds 14-19 (IC(50) values of 4.2 ± 0.95, 0.025 ± 0.003, 1.2 ± 0.45, 1.2 ± 0.1, 0.028 ± 0.003, and 0.069 ± 0.005 nM, respectively) showing the highest inhibitory activity. The results from the in vitro experiments indicated that only 15-17 bind to the AR.  相似文献   

20.
The effect of human platelet functions of 9,11-dithio analogues of prostaglandin endoperoxide was investigated. Methyl (5z,9α,11α,13e,15S)-9,11-epidithio-15-hydroxyprosta- 5,13-dienoate induced platelet aggregation, while the 9β,11β-epimer was inactive. The platelet aggregation caused by the 9α,11α-dithio analogue was associated with serotonin release from platelets, and was inhibited by methyl ester of prostaglandin I2 (prostacyclin) but not by indomethacin.  相似文献   

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