首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Neridienone-A (12β-hydroxy-pregna-4,6,16-triene-3,20-dione), neridienone-B (20β,21-dihydroxy-pregna-4,6-diene-3,12-dione), 12β-hydroxy-pregna-4,6-diene-3,20-dione, 12β-hydroxy-pregn-4-ene-3,20-dione and 12β-hydroxy-16α-methoxy-pregna-4,6-diene-3,20- dione were obtained from the root bark of Nerium odorum.  相似文献   

2.
The microbiological reduction of the 20-carbonyl group of steroids has been investigated. Candida pulcherrima IFO 0964 and Sporotrichum gougeroti IFO 5982 converted the following substrates into the corresponding 20β-hydroxy derivatives (yields of the products are indicated in parentheses): Reichstein’s Compound S (60~70%) and 17α,21-dihydroxypregna-l,4-diene- 3,20-dione (40~80%). Rhodotorula glutinis IFO 0395 converted the following substrates into the corresponding 20α-hydroxy derivatives: Reichstein’s Compound S (65%), 17 α,21-dihydroxy- pregna-l,4-diene-3,20-dione (80%), llβ,l7α-dihydroxypregn-4-ene-3,20-dione (45%) and 17α, 19,21 -trihydroxypregn-4-ene-3,20-dione (10%).  相似文献   

3.
Hydroxylation of l7α-acetoxy-6-chloro-16-methylene-4,6-pregnadiene-3,20-dione (Chlorosuperlutin, I) byCunninghamella blakesleeana yielded a 15β-hydroxyderivative II. Analogous transformation of 17α-acetoxy-16-methylene-4,6-pregnadiene-3,20-dione (Superlutin, IV) included a hydroxylation in position 15β and probably also in 11β with a concomitant reduction of the 6,7-double bond.  相似文献   

4.
The metabolic fate of 9-fluoro-11β,16α,17,21-tetrahydroxy-l, 4-pregnadiene-3,20-dione cyclic 16,17-acetal with 2-14C-acetone, triaacinolone acetonide (TA) was studied in rabbits, dogs, monkeys and rats and found to be qualitatively similar in all species. In the dog, rat and monkey the major excretory route was the feces irrespective of the mode of administration. In the rabbit the excreted radioactivity was equally distributed between urine and feces. The metabolites were isolated by preparative thin layer chroma tography, located by autoradiography, eluted and analyzed by MS, IR, UV and NMR. The major metabolites of triamcinolone acetonide (TA) were identified as the C-21 carboxylic acids of TA and of the 6β hydroxy-TA,(6β-OH-TA) and the previously identified (1,2) 6β-OH-TA. In addition MS and UV data indicate the presence of 9-fluoro-11β,16α, 17-trihydroxy-3,20-dioxo-1,4,6-pregnatrien-21-oic acid cyclic 16,17 acetal with 2-14C-acetone.  相似文献   

5.
A six step transformation of prednisolone to 17α,21-dihydroxy-9β,11β-epoxy-16α-amethylpregna-1,4-diene-3,20-dione 21-acetate has been achieved in 13% unoptimised yield. Novel conditions for effecting a Mattox rearrangement and double dehydration of prednisolone were identified. Enhanced knowledge on the oxidation of silyl Δ19,20-enol ethers and structural factors that impact the success of the oxidation are also presented.  相似文献   

6.
The potential for biotransformation of the substrate 17β-hydroxyandrost-4-en-3-one (testosterone) by six filamentous fungi, namely, Rhizopus oryzae ATCC 11145, Mucor plumbeus ATCC 4740, Cunninghamella echinulata var. elegans ATCC 8688a, Aspergillus niger ATCC 9142, Phanerochaete chrysosporium ATCC 24725 and Whetzelinia sclerotiorum ATCC 18687, was investigated. In this study both free cells and macerated mycelia immobilised in calcium alginate were utilised and the results (products, % yields, % transformation) were compared. In general the encapsulated cells of the microorganisms effectively generated products similar to those found using free cells. However, with immobilised macerated mycelia, isolation of the transformation products was expedited by the simple work up procedure, and their purification was facilitated by the absence of fungal secondary metabolites. Twenty seven analogues of testosterone were generated, wherein the androstane skeleton was functionalised at C-1β, -2β, -6β, -7α, -11α, -14, -15α, -15β and -16β by the moulds. Redox chemistry was also observed. Seven of the analogues, 6β,11α,17β-trihydroxyandrost-4-en-3-one, 6β,14α,17β-trihydroxyandrost-4-en-3-one, 2,6β-dihydroxyandrosta-1,4-diene-3,17-dione, 2β,16β-dihydroxyandrost-4-ene-3,17-dione, 2β,6β-dihydroxyandrost-4-ene-3,17-dione, 2β,15β,17β-trihydroxyandrost-4-en-3-one and 2β,3α,17β-trihydroxyandrost-4-ene, were novel compounds. Five others, namely, 7α,17β-dihydroxyandrost-4-en-3-one, 6β,14α-dihydroxyandrost-4-ene-3,17-dione, 15α,17β-dihydroxyandrost-4-en-3-one, 16β,17α-dihydroxyandrost-4-en-3-one and 2β,16β,17β-trihydroxyandrost-4-en-3-one, were fully characterised for the first time.  相似文献   

7.
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   

8.
The conversion of pregna-4,9(11)-diene-17alpha,21-diol-3,20-dione 21-acetate (I) and 17,21-diacetate (VI) by Nocardioides simplex VKM Ac-2033D was studied. The major metabolites formed from I were identified as pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 21-acetate (II) and pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione (IV). Pregna-4,9(11)-diene-17alpha,21-diol-3,20-dione (III) and pregna-1,4,9(11)-triene-17alpha,20beta,21-triol-3-one (V) were formed in minorities. Biotransformation products formed from VI were pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 17,21-diacetate (VII), pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 21-acetate (II), pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione (IV), pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 17-acetate (VIII), pregna-1,4,9(11)-triene-17alpha,20beta,21-triol-3-one (V). The conversion pathways were proposed including 1(2)-dehydrogenation, deacetylation, 20beta-reduction and non-enzymatic migration of acyl group from position 17 to 21. The conditions providing predominant accumulation of pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 21-acetate (II) from I and pregna-1,4,9(11)-triene-17alpha,21-diol-3,20-dione 17-acetate (VIII) from VI in a short-term biotransformation were determined.  相似文献   

9.
The fermentation of progesterone by Colletotrichum antirrhini SC 2144 was examined. Instead of 15 alpha-hydroxyprogesterone, the reported product, this fungus converted progesterone to androst-4-ene-3,17-dione, androsta-1,4-diene-3,17-dione, 14 alpha-hydroxyandrosta-1,4-diene-3,17-dione, 11 alpha-hydroxypregn-4-ene-3,20-dione, 14 alpha-hydroxypregn-4-ene-3,20-dione, and a hitherto undescribed compound, 14 alpha-hydroxypregna-1,4-diene-3,20-dione.  相似文献   

10.
Several new 4,19-substituted steroids and previously synthesized corticosteroids were assayed for affinity to type 1 receptors in human mononuclear leukocytes. 11 beta,19-epoxy-4,21-dihydroxypregn-4-ene-3,20-dione (2) was hydrogenated with Pd-C to yield a mixture of all four dihydro derivatives 5, accompanied by 4,21-diacetoxy-11 beta,19-epoxy-3-hydroxypregnan-20-one (6) and 21-acetoxy-11 beta,19-epoxy-4-hydroxypregnane-3,20-dione (7). With hot acetic + p-toluenesulfonic acid 5 underwent rearrangement to 21-acetoxy-11 beta,19-epoxypregn-5-ene-4,20-dione (8) Pd-C hydrogenation of 3,21-diacetoxy-5 beta,19-cyclopregna-2,9(11)-diene-4,20-dione (10) gave 3,21-diacetoxy-5 beta,19-cyclopregn-5-ene-4,20-dione (11) and the 9,11-dihydro derivative of the latter. Treatment of 10 with warm HCl furnished 19-chloro-4,21-dihydroxypregna-4,9(11)-diene-3,20-dione (13). Pd-C hydrogenation of its diacetate 14 afforded the 4,5-dihydro derivative 18, 19-chloro-21-acetoxypregn-9(11)-en-20-one (15), its 4-acetoxy derivative 16 and the 3,4-diacetoxy derivative 17. When tested in a radioreceptor assay in human mononuclear leukocytes the synthesized compounds showed only low relative binding affinities (RBA) to type 1 receptor, the highest being 0.72% for 13 (aldosterone = 100%). For comparison, other RBA in this system were: 19-noraldosterone, 20%; 18-deoxyaldosterone, 5.8%; 18-deoxy-19-noraldosterone, 4.7%; 18,21-anhydroaldosterone, 0.37%; 17-isoaldosterone, 7.6% and apoaldosterone, 4.3%  相似文献   

11.
A novel 6/8/6-membered taxane with a rare C-12(13)-double bond and rare 2(3→20)abeotaxane were isolated from the needles of Taxus canadensis. Their structures were characterized as 7β,9α,10β-triacetoxytaxa-4(20),12-diene-2α,5α,11β-triol (1) and 2α,7β,10β-triacetoxy-5α-hydroxy-2(3→20)abeotaxa-4(20),11-diene-9,13-dione (2) on the basis of 1D and 2D spectroscopic data. 1 is the first example of a natural taxane without substitution at both C-13 and C-14.  相似文献   

12.
Biotransformations of steroid compounds: androstenedione, testosterone, progesterone, pregnenolone and DHEA using Chaetomium sp. 1 KCH 6651 strain as a biocatalyst were investigated. The microorganism proved capable of selective hydroxylation of the steroid substrates. Androstenedione was converted to 14α-hydroxyandrost-4-en-3,17-dione (in over 75% yield) and 6β-hydroxyandrost-4-en-3,17-dione (in low yield), while testosterone underwent regioselective hydroxylation at 6β position. Progesterone was transformed to a single product—6β,14α-dihydroxypregnan-4-en-3,20-dione in high yield, whereas biotransformation of DHEA resulted in the formation of 7α-hydroxy derivative, which was subsequently converted to 7α-hydroxyandrost-4-en-3,17-dione.  相似文献   

13.
The pharmacological activities of four pregnane derivatives: 17alpha-hydroxy-16beta-methylpregna-4,6-diene-3,20-dio ne (7), 17alpha-acetoxy-16beta-methylpregna-4,6-diene-3,20-dio ne (8), 17alpha-acetoxy-6-bromo-16beta-methylpregna-4,6-diene- 3,20-dione (10), and 17alpha-acetoxy-6-chloro-16beta-methylpregna-4,6-diene -3,20-dione (11), were determined. The derivatives were evaluated on gonadectomized male hamster flank organs and seminal vesicles. The results indicate that topical applications of testosterone (T) on the flank organs increased the diameter of the pigmented spot. Similarly, the same phenomenon occurred on the glands treated with compound 11, whereas compound 10 decreased the size of the spot significantly. In this study, we determined the effects of several new steroids on the conversion of T to DHT in flank organs and seminal vesicles. The results show that compound 10 inhibited T conversion to DHT, but compound 11, at a dose of 200 microg, stimulated T conversion in both flank organs and seminal vesicles. However, when 2 mg of compound 11 was applied, it inhibited the conversion of T to DHT, suggesting that this compound also represses gonadotropin release. The difference between compounds 10 and 11 involves the electronegativity of the halogen at the C-6 position of the progesterone skeleton. These data clearly indicate that by decreasing the electronegativity of the halogen at C-6 (compound 10), 5alpha-reductase is inhibited in both tissues and at different pHs. On the other hand, when the electronegativity of the halogen atom was increased (11), there was a much lower inhibitory effect on the conversion of T to DHT.  相似文献   

14.
Recognition of D-homoannulation by proton and carbon NMR spectra   总被引:1,自引:0,他引:1  
L L Smith  E L Ezell 《Steroids》1989,53(3-5):513-531
One-and two dimensional proton and carbon NMR spectra of the D-homoannulated rearrangement product of triamcinolone (9 alpha-fluoro-11 beta,16 alpha,17 alpha, 21-tetrahydroxy-pregna-1,4-diene-3,20-dione) establish its structure as that of 9 alpha-fluoro-11 beta,16 alpha,17 alpha-trihydroxy-17 beta-hydroxy-methyl-D-homoandrosta-1,4-diene-3,17 alpha-dione. These methods accord ready recognition of D-homoannulation of C21-17-hydroxy-20-ketosteroids.  相似文献   

15.
A novel 6/8/6-membered taxane with a rare C-12(13)-double bond and rare 2(3→20)abeotaxane were isolated from the needles of Taxus canadensis. Their structures were characterized as 7β,9α,10β-triacetoxytaxa-4(20),12-diene-2α,5α,11β-triol (1) and 2α,7β,10β-triacetoxy-5α-hydroxy-2(3→20)abeotaxa-4(20),11-diene-9,13-dione (2) on the basis of 1D and 2D spectroscopic data. 1 is the first example of a natural taxane without substitution at both C-13 and C-14.  相似文献   

16.
(22R,23R)-22,23-dihydroxystigmast-4-en-3-one, (22R,23R)-22,23-dihydroxystigmast-4-en-3,6-dione, (22R,23R)-3β,5α,6β,22,23-pentahydroxystigmastane, (22R,23R)-5α,6α-oxido-3β,22,23-trihydroxystigmastane, (22R,23R)-5β,6β-oxido-3β,22,23-trihydroxystigmastane, and (22R,23R)-3β,6β,22,23-tetrahydroxystigmast-4-ene were synthesized. Their cytotoxicities were comparatively studied using the MCF-7 line of carcinoma cells of human mammary gland and cells of human hepatoma of the Hep G2 line.  相似文献   

17.
After instillation of 3H-dexamethasone into the eyes of a rabbit, 3H-9α-fluoro-11β-hydroxy-16α-methyl-1,4-androstadiene-3,17-dione was found in the aqueous humor. The same metabolite was also formed by incubating 3H-dexamethasone with the anterior ocular tissues of rabbit. Identification of 3H-9α-fluoro-11β-hydroxy-16α-methyl-1, 4-androstadiene-3, 17-dione was performed by its mobility on a thin layer plate and by proving its radiochemical homogeneity after recrystailization with the unlabeled sample which had been synthesized from dexamethasone by oxidation with sodium bismuthate.When dexamethasone disodium phosphate was instilled into rabbit's eyes, it was hydrolyzed to free dexamethasone and then metabolized to 9α-fluro-11β-hydroxy-16α-methyl-1, 4-androstadiene-3,17-dione.  相似文献   

18.
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   

19.
An attempt was made to clarify how Pellicularia filamentosa f. sp. microsclerotia IFO 6298 capable of hydroxylating C21-steroids at the C-19 position converts C19-steroids, especially monohydroxyderivatives of androst-4-ene-3, 17-dione. Such substrates as 11β-hydroxyandrost-4-ene-3,17-dione (I), androst-4-ene-3, 11, 17-trione (II), androsta-1,4-diene-3, 17-dione (III), 11β-hydroxyandrosta-1,4-diene-3,17-dione (IV), 14α-hydroxyandrost-4-ene-3, 17-dione (V), 15α-hydroxyandrost-4-ene-3, 17-dione (VI) and 9α-hydroxyandrost-4-ene-3, 17-dione (VII) were converted by the organism. All the main and several minor products were then isolated and identified. As a result it is concluded that this organism converts I and II into 14α-hydroxyandrost-4-ene-3,11,17-trione, III and IV into 14α-hydroxyandrosta-1,4-diene-3,1l,17-trione, V into 11α 14α dihydroxyandrost-4-ene-3, 17-dione (main) and 11β, 14α-dihydroxyandrost-4-ene-3, 17-dione (minor, a tentative structure), VI into 11β, 15α-dihydroxyandrost-4-ene-3,17-dione (main) and 15α-hydroxyandrost-4-ene-3,11,17-trione (minor, a tentative structure) and VII into 9α, 14α-dihydroxyandrost-4-ene-3, 17-dione (main) and 6β, 9α-dihydroxyandrost-4-ene-3,17-dione (minor).

In addition, the structural requirement of substrate for the 19-hydroxylation catalyzed by the organism and the influence of a hydroxyl group on steroid nucleus upon the 11β- and 14α-hydroxylations and the 11β-OH-dehydrogenation was discussed.  相似文献   

20.
中国南海侧扁软柳珊瑚中孕甾烷类化学成分的研究(英文)   总被引:1,自引:0,他引:1  
从南海侧扁软柳珊瑚Subergorgia suberosa的二氯甲烷-甲醇提取物中首次分离鉴定了8个孕甾烷类化合物,经波谱鉴定为3β-O-palmitoyl-pregn-5-ene-20-one-3-ol (1),3β-O-palmitoyl-5α-pregn-20-one-3-ol (2),5α-pregn-1-ene-3,20-dione (3),3β,5α-pregn-20-one-3-ol (4),3β-pregn-5-ene-20-one-3-ol (5),3β,5β-pregn-20-one-3-ol (6),5β-pregn-3,20-dione (7),pregn-4-ene-3,20-dione (8).其中化合物1,2为新化合物.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号