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1.
The synthesis of 17-ethynyl-11-oxatestosterone, both from 11-oxa-5 alpha-pregnane-3,20-dione and, via a 3,17-dioxygenated 9-oxo 9,12-seco 11-nor 5 alpha-androstane-12-oic ester, from 3 beta-acetoxy-17-hydroxy-5 alpha-pregnan-12-one--two products available from hecogenin--is reported. The new hormone analogue shows significant progestational activity in the Clauberg test and relatively weak activity in a post-coital antifertility assay.  相似文献   

2.
The syntheses of 11-oxa and 17alpha-hydroxymethyl analogues of steroid hormones and their derivatives are reported and some of their biological activities are discussed. Generally, the replacement of the 11-methylene group by oxygen results in a diminution of the progestational, androgenic-anabolic, and estrogenic activities. This effect is least pronounced in the case of the progestational activity of 11-oxa-ethisterone and particularly strong in the case of the uterotropic activity of 11-oxa-estradiol. 17alpha-acetoxymethylprogesterone and 17alpha-hydroxymethylprogesterone were synthesized by 2 pathways, 1 of which can be advantageously applied also to the synthesis of 17alpha-acyloxymethyl and 17alpha-hydroxymethyl glucocorticoids. 17alpha-acetoxymethylprogesterone was inactive in the Clauberg test even at high doses.  相似文献   

3.
A new progesterone analogue, 17-methoxymethylprogesterone, was synthesized from pregnenolone by two pathways, one involving as intermediate a 17-hydroxymethylated adduct, the other one by methoxymethylation of a 17,20-lithium enolate with bromomethoxymethane. The product shows significant progestational activity.  相似文献   

4.
The effect glucocorticoids on the synthesis and degradation of phosphoenolpyruvate carboxykinase (GTP)(EC4.1.1.32) in rat liver and kidney in vivo was studied immunochemically. The glucocorticoid analogue triamcinolone (9alpha-fluoro-11beta, 21-dihydroxy-16alpha,17alpha-isopropylidenedioxypregna-1,4-diene-3,20-dione) increased the synthesis rate of the kidney enzyme in starved animals. Both triamcinolone and cortisol decreased the synthesis rate of hepatic phosphoenolpyruvate carboxykinase (GTP) in fed and starved rats, but were without effect on the degradation rate of the enzyme. This effect of triamcinolone in liver was reversed by injection of dibutyryl cyclic AMP. However, in diabetic animals glucocorticoids increased the synthesis rate of hepatic phosphoenolpyruvate carboxykinase (GTP). Triamcinolone administration to starved rats in vivo is shown to cause an increase in the portal blood concentrations of insulin and glucose. Since the physiological de-inducer of liver phosphoenolpyruvate carboxykinase (GTP) is insulin, this is the probable cause of the decrease in the synthesis rate of the hepatic enzyme noted when glucocorticoids are administered to non-diabetic animals.  相似文献   

5.
The cyp11 includes cyp11a and cyp11b in most mammals and teleosts, encoded cholesterol side chain lyase and 11β-hydroxylase, respectively. It is essential in steroid hormone synthesis. However, studies on the regulation of cyp11 are limited, especially in teleosts. In this study, the molecular characterization and function of cyp11a and cyp11b of black rockfish was investigated. Both of them showed high homology with other teleost counterparts by phylogenetic analysis. The expression of cyp11a and cyp11b exhibited a clear sexually dimorphic pattern, with a higher expression level in testis than that of in ovaries. During the different developmental stages (40 dpf, 80 dpf, 190 dpf, 360 dpf, 720 dpf), the expression of cyp11a was earlier than cyp11b. In situ hybridization results showed that cyp11a and cyp11b were mainly expressed in oogonia and oocytes of the ovary. They were located in spermatogonia and interstitial compartment in the 1.5-year-old gonads, and spermatocytesgonia and the peritubular myoid cell of the testis in the 2.5-year-old gonads. To explore the distinct roles of cyp11a and cyp11b in gonads, oestrogen and androgens were used to stimulate the primary testicular and ovarian cells. The expressions of cyp11a and cyp11b were tested under different dose of 17α-methyltestosterone (17α-MT) and 17β-estradiol (E2). The results showed cyp11a was significantly increased at 10−6 mol ml–1 of 17α-MT and 10−8 mol ml–1 of E2 in ovary and 10−10 mol ml–1 of 17α-MT and E2 in testis, while cyp11b was significantly decreased after 17α-MT and E2 treatment. These results indicated that cyp11a and cyp11b were likely to have different functions, and also implied they might play an important roles in the differentiation of gonads and the synthesis of steroids in black rockfish.  相似文献   

6.
The title compound 17 has been synthesized for the use as hapten in the development of a competitive enzyme immunoassay for estrogen sulfamates. The synthesis started from estradiol diacetate 2. Oxyfunctionalization at C-11 to give 11alpha-hydroxy steroid 8 was accomplished by hydroboration/alkaline hydrogen peroxide oxidation of the 9(11)-dehydro derivative 7, which was obtained from compound 2 via 9-hydroxylation with dimethyldioxirane. After transformation of compound 8 into the allyl ether 9, the side chain was thio-functionalized at the omega-position affording the thioate 11 in two steps. Selective silylether deprotection at position 3 followed by sulfamoylation gave the sulfamate 19, which in turn was demasked at position 17 and treated with sodium borohydride/aluminum chloride to liberate the side chain thiol. Alternatively, title compound 17 was synthesized via the disulfides 13-16. For the preparation of the immunogen the title compound 17 was coupled to bovine gamma globulin in a two-step procedure using an amine and thiol specific bifunctional crosslinker. The immunization of rabbits resulted in the formation of antibodies which clearly discriminated the sulfamoylated estrogens from the non-esterified estrogens. The use of a biotinylated hapten derivative as a tracer in combination with a streptavidin-peroxidase-tetramethylbenzidine based detection system allowed the measurement of estradiol 3-sulfamate (1) in the range of about 1 to 1000 pg/well.  相似文献   

7.
Structural analysis, a purification scheme and stability information on a fluorescent cholesterol analogue, which has been used as a probe in several model and biological systems, are presented. The proposed structure for the fluorophore, cholestatrien-3 beta-ol, closely resembles that of cholesterol. However, problems of low yield during synthesis and rapid decomposition have impeded its use. This study concerns the synthesis and purification of cholestatrien-3 beta-ol by reverse phase high performance liquid chromatography (HPLC). Unlike cholestatrien-3 beta-ol recrystallized from solvents, the fluorescent sterol purified by HPLC was stable over several months at -70 degrees C either as a white, crystalline powder or in ethanolic solution. In model membranes the fluorescence of cholestatrien-3 beta-ol was stable to ultraviolet (UV) light. A simple spectroscopic assay for purity is presented. Included are detailed absorbance, fluorescence, mass, 1H-NMR, and 13C-NMR spectral analyses. The data confirm the structure of cholestatrien-3 beta-ol proposed, but not proven, over 50 years ago, delta 5,7,9(11)-cholestatrien-3 beta-ol.  相似文献   

8.
A new practical synthesis of 17alpha-acetoxy-11beta-(4-N, N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione (CDB-2914) is described. The synthesis gives easily isolable solids at all steps and is amenable to large-scale process.  相似文献   

9.
Total synthesis of a new prostaglandin analogue, 11-deoxy-4,4-dimethyl-4-sil-prostaglandin E1, is carried out through synthesis of a silicon-containing alpha-chain precursor and a 2-substituted cyclopentenone derivative followed by their cuprate-induced interaction.  相似文献   

10.
Evidence is presented to show that GR2/2132 is longer-acting than its 3-ketone analogue vhen administered subcutaneously in a modified progestational test in the rabbit and in modified anti-estrogenic tests in rats and mice.  相似文献   

11.
Biomedical studies with animal models have demonstrated that cis-9, trans-11 conjugated linoleic acid (CLA), the predominant isomer found in milk fat from dairy cows, has anticarcinogenic effects. We recently demonstrated endogenous synthesis of cis-9, trans-11 CLA from ruminally derived trans-11 C18:1 by Delta(9)-desaturase in lactating dairy cows. The present study further examined endogenous synthesis of cis-9, trans-11 CLA and quantified its importance by increasing substrate supply using partially hydrogenated vegetable oil (PHVO) as a source of trans-11 C18:1 and blocking endogenous synthesis using sterculic oil (SO) as a source of cyclopropene fatty acids which specifically inhibit Delta(9)-desaturase. Four cows were abomasally infused with 1) control, 2) PHVO, 3) SO, and 4) PHVO+SO in a 4 x 4 Latin square design. With infusion of PHVO, cis-9, trans-11 CLA was increased by 17% in milk fat. Consistent with inhibition of desaturase, SO treatments increased milk fat ratios for the fatty acid pairs effected by Delta(9)-desaturase, C14:0/cis-9 C14:1, C16:0/cis-9 C16:1, and C18:0/cis-9 C18:1. The role of endogenous synthesis of CLA was evident from the 60-65% reduction in cis-9, trans-11 CLA which occurred in milk fat with SO treatments. cis-9 C14:1 originates from desaturation of C14:0 by Delta(9)-desaturase and can be used to estimate the extent of SO inhibition of Delta(9)-desaturase. When this correction factor was applied, endogenous synthesis was estimated to account for 78% of the total cis-9, trans-11 CLA in milk fat. Thus, endogenous synthesis was the major source of cis-9, trans-11 CLA in milk fat of lactating cows.  相似文献   

12.
Acs P  Jakab B  Takács A  Kollár L 《Steroids》2007,72(8):627-632
11-Carboxamido-androst-4,9(11)-dienes were synthesized from the corresponding 11-iodo-androst-4,9(11)-diene derivative in palladium-catalyzed aminocarbonylation reaction under mild reaction conditions. The synthesis of the iodo-alkene substrate is based on the transformation of the 11-keto derivative to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). The 11-carboxamides were synthesized in moderate to high isolated yields by using simple alkyl/arylamines or amino acid methylesters as N-nucleophiles. The highly active palladium catalysts enable the homogeneous catalytic functionalization at one of the most hindered position (C-11) of the steroidal skeleton.  相似文献   

13.
Rhinopoma hardwickei hardwickei has an annual reproductive cycle. Although many of the females become inseminated from the latter half of February until about the middle of April, ovulation has not been recorded until the 11th of March. A single follicle reached full development and released one ovum from either of the ovaries with nearly equal frequency, and a single conceptus was carried in the ipsilateral uterine cornu during each cycle. The embryo descended into the uterus as an early morula and attained the bilaminar blastocyst stage before undergoing implantation. As the morula advanced in age, the embryonic surface of the zona became progressively more basophilic. Hence in advanced morulae, the inner surface of the zona pellucida took a dark stain with hematoxylin and appeared like a distinct thin membrane, while the rest of the thickness of the zona was eosinophilic. Although progestational changes commenced in both uterine cornua, they became augmented in the uterine cornu on the side of ovulation and blastocyst attachment. After blastocyst attachment, the contralateral cornu reverted to an anestrus condition. The progestational changes became less conspicuous from the cranial to the caudal end of the uterus. Evidently, there was a linear gradient in the progestational response of the uterus with the cranial end being most responsive and the caudal end least responsive. The precise mechanism which brings this about is not known.  相似文献   

14.
A radioimmunoassay (RIA) method is described for the determination of 4-androstene-3, 11, 17-trione (11-oxo-androstenedione) in human plasma. 4-androstene-3, 11, 17-trione 3-(0-carboxymethyl) oxime-bovine serum albumin conjugate was used to generate highly specific antiserum in rabbits. Cross reactivities of several other steroids with the antiserum were less than 4%. [1,2-3H] 4-androstene-3, 11, 17-trione was synthesized from [1,2-3H] 17 alpha, 21-dihydroxy-4-pregnene-3, 11, 20-trione. The intra- and interassay variation was 7.3% and 9.8%, respectively. The mean serum 4-androstene-3, 11, 17-trione level for healthy young subjects was 2.37 +/- 0.56 nM (X +/- SD) in males and 3.16 +/- 0.43 nM in females at 8 a.m. During the night, there was a marked decrease in serum level, giving at 11 p.m. 0.87 +/- 0.33 and 1.15 +/- 0.52 nM, respectively. During ACTH stimulation tests, 4-androstene-3, 11, 17-trione increased from 1.81 +/- 0.58 to 2.32 +/- 0.69 nM, while in dexamethasone suppression tests a decrease from 3.20 +/- 0.03 nM was seen. In contrast, HCG administration on 3 consecutive days did not influence plasma concentrations of 4-androstene-3, 11, 17-trione.  相似文献   

15.
The conversion of 21-acetoxy-pregna-4(5),9(11),16(17)-triene-21-ol-3,20-dione (I) by Nocardioides simplex VKM Ac-2033D was studied purposed selective production of its 1(2)-dehydroanalogues—value precursors in the synthesis of modern glucocorticoids starting from 9-hydroxyandrostenes. 21-Acetoxy-pregna-1(2),4(5),9(11),16(17)-tetraene-21-ol-3,20-dione (II), pregna-4(5),9(11),16(17)-triene-21-ol-3,20-dione (III) and pregna-1(2),4(5),9(11),16(17)-tetraene-21-ol-3,20-dione (IV) were revealed as metabolites, and the structures were confirmed by mass spectrometry and 1H nuclear magnetic resonance (NMR) spectroscopy. The metabolic pathways of I by N. simplex included 1(2)-dehydrogenation and deacetylation. The sequence of the reactions was shown to depend on the transformation conditions. The presence of both soluble and membrane associated steroid esterases in N. simplex was demonstrated using cell fractionation. Unlike inducible 1(2)-dehydrogenase, steroid esterase was shown to be constitutive. The conditions providing selective accumulation of II from I by whole N. simplex cells were determined.  相似文献   

16.
Synthesis of (Z)-(2,3-bis-hydroxymethyl)methylenecyclopropane analogues of nucleosides adenosine 10a, 10b, 10c and 17 is described. Epimerization of Feist's acid (11) using acetic anhydride gave cyclic anhydride 12 which was reduced in situ to give diol 13. Acetylation (compound 14) followed by addition of bromine led to dibromo derivative 15. Alkylation-elimination of adenine with 15 afforded, after deacetylation, analogue 10a. Similar treatment of 2-amino-6-chloropurine and 2,6-diaminopurine led to diacetates 16 and 18. Deprotection then gave compounds 17 and 10c. Hydrolysis of 17 furnished guanine analogue 10b. Compounds 10a, 10b or 10c were inactive against HCMV, HSV-1, HSV-2, EBV VZV and HBV. Analogues 10a and 10b were also assayed for anti-HIV activity. Compound 10a was effective in HIV-1/MT-2 culture with EC50/CC50 33/> 100 microM but 10b was inactive. Analogue 10a was not a substrate for adenosine deaminase.  相似文献   

17.
The structure of 13-ethyl-11-methylene-18,19-dinor-17alpha-pregn-4-en-20-yn-16beta,17-diol (3, 16beta-OH desogestrel), a by-product obtained in the last step of the synthesis of desogestrel (1) by reaction of monolithium acetylide-ethylenediamine complex with 13beta-ethyl-11-methylenegon-4-en-17-one (2), is here reported. The structural assignments were supported by NMR 1H-, 13C-, 1H-1H COSY, 1H-13C HSQC, COLOC) and mass spectroscopy, and the configuration at the C-16 and C-17 stereocentres was established by X-ray crystallography. When the same 17-ketoderivative 2 was treated with a non-alkylating base, such as potassium tert-butoxide, instead of the expected 16-hydroxylated ketone, a dimeric product, 13beta-ethyl-16-[2'-(des-D-13"-carboxy-13"beta-ethyl-11"-methylenegon-4"-en-14"-yl)-ethyliden]-11-methylenegon-4-en-17-one (4), was isolated in good yield; it was characterized by NMR, mass, ultraviolet spectroscopy, and chemical transformations. Compounds 3 and 4 originate from the high reactivity of the 16-methylenic position of the 17-keto substrate (2) toward molecular oxygen under basic conditions.  相似文献   

18.
Previous studies of the round goby (Neogobius melanostomus Pallas, 1814), an invasive fish species in the Laurentian Great Lakes of North America, have shown that this species has the ability to both synthesize and smell steroids that have a 5 beta-reduced and 3 alpha-hydroxyl (5 beta,3 alpha) configuration. An enzyme-linked immunoassay (EIA) for 3 alpha-hydroxy-5 beta-androstane-11,17-dione (11-O-ETIO) has been used to show a substantial rise in the rate of release of immunoreactive compounds into the water when males are injected with salmon gonadotropin releasing hormone analogue. Similar increases were noted for 11-ketotestosterone and 17,20 beta-dihydroxypregn-4-en-3-one. Partitioning of the extracts between diethyl ether and water showed the presence of both free and conjugated immunoreactive 11-O-ETIO. Only conjugated immunoreactivity was found in urine (implying that free steroid is released via the gills). The identity of the conjugates was probed by using HPLC, EIA, and mass spectrometry and removal of sulfate and glucosiduronate groups. Immunoreactivity in the conjugated fraction was found to be due mainly to 3 alpha,17beta-dihydroxy-5 beta-androstan-11-one 17-sulfate. However, the evidence was also strong for the presence in water extracts of substantial amounts of 3 alpha-hydroxy-5 beta-androstane-11,17-dione 3-glucosiduronate (which could be detected only by EIA after removal of the glucosiduronate group with beta-glucuronidase). There were also small amounts of 3 alpha-hydroxy-5 beta-androstane-11,17-dione 3-sulfate and 3 alpha,17beta-dihydroxy-5 beta-androstan-11-one 17-glucosiduronate. These studies give some idea of the types, amounts, and ratios of 11-O-ETIO derivatives that are released by reproductive N. melanostomus and will aid further research into the putative pheromonal roles of 5 beta,3 alpha-reduced androgens in this species.  相似文献   

19.
In the course of our study to determine the cross-sensitivity between CPT-11 and its active metabolite, SN-38, we found a SN-38-resistant human pancreatic tumor cell line, QGP-1N, which shows sensitivity to CPT-11. The IC50 of SN-38 was 152 times greater for QGP-1N than for SUIT-2, also a human pancreatic tumor cell line, whose IC50 of CPT-11 was similar to that for QGP-1N. The uptakes of CPT-11 and SN-38 and the intracellular conversion of CPT-11 to SN-38 could not explain the difference in sensitivity. DNA synthesis of QGP-1N cells was inhibited by CPT-11 which did not affect that of SUIT-2, while SN-38 inhibited the DNA synthesis of SUIT-2 at lower concentrations than that of QGP-1N. The inhibition test of topoisomerase I catalytic activity by CPT-11 or SN-38 revealed no difference in the biochemical properties of the topoisomerase I enzymes to the compounds between these two cell lines. These results indicate that CPT-11 should have its own inhibitory effect on DNA synthesis through a yet unknown mechanism in QGP-1N cells, although SN-38 plays an essential role in the antitumor activity of CPT-11 in SUIT-2 cells. In some cases, the antitumor effect of CPT-11 might be consequent not only on SN-38 but also on CPT-11 itself.  相似文献   

20.
Two solution syntheses of cyclo(11----5 epsilon)-[Lys5]substance P-(5-11) (CLP) were carried out. The first synthesis involved the stepwise elongation of the peptide chain starting from glycine tert-butyl ester. At the stage of hexapeptide deprotection, the cleavage of Boc and But groups was accompanied by tert-butylation of the Met residue. Cyclization was carried out via a pentafluorophenyl ester intermediate. The benzyloxycarbonyl-cyclopeptide (Z-CLP) formed was deprotected by catalytic transfer hydrogenation. A (3 + 4) block coupling strategy was used in course of the repeated preparation of the linear precursor of CLP. Optimization of the cyclization and subsequent deprotecting stages lead to increased yields and facilitated the synthetic procedure. Z-CLP was found to possess myotropic activity on isolated guinea pig ileum (alpha = 0.55 +/- 0.18; pD2 = 7.97 +/- 0.20), whereas CLP was inactive in these experiments. Z-CLP causes a slight two-phase effect on arterial pressure in rats, CLP being inactive. Similar to substance P, CLP displays an antidepressant-like effect in mice as indicated by the swimming test.  相似文献   

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