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1.
A series of 12α-hydroxy steroids with varying side chains was prepared, and their 24-hour acetylation yields were compared, l2α-Hydroxy-5β-pregnan-20-one () was prepared from 3α, 12α-diacetoxy-5β~pregnan-20-one () and also by side chain degradation of 12α-acetoxy-5β-cholanoic acid (). 21-Benzyl-5β-pregnan-12α-ol () was synthesized by hydrogenation of the 21-benzylidine derivative of ketone . 23-Pheny1-5β-norcholan-12α-ol () was obtained by the Grignard reaction of 2-phenyl-ethylmagnesium bromide and ketone , dehydration, hydrogenation and hydride reduction; a similar sequence produced 20-methyl-5β-pregnan-12α-ol (). The acetylation results (Table 11) imply that branching at C-20 may be more significant for 12α-hydroxyl reactivity than side chain length or type. An additional compound with an unbranched side chain, 21-nor-5β-cholan-12α-ol (), was synthesized by a Grignard reaction on the 21-bromo intermediate . Acetylation rates determined by glc indicate (Table 111) That compounds with unbranched side chains have 12α-hydroxyl groups about ten times as reactive as their analogs with 20-methyl groups. 相似文献
2.
A novel synthesis of 16α-hydroxy-4-androstene-3,17-dione (), 16α-hydroxy-4-androstene-3, 6,17-trione (), 17β-amino-5-androsten-3β-ol () and 17β-amino-4-androsten-3-one (14) is described. 16α-Bromoacetoxy-4-androstene-3, 17-dione (), 16α-bromoacetoxy-4-androstene-3, 6,17-trione () and 17β-bromoacetylamino-4-androsten-3-one () were synthesized as potentially selective irreversible inhibitors of androgen aromatases. 16α-Bromo-4-androstene-3,17-dione () and 16α-bromo-4-androstene-3, 6,17-trione () were converted to compounds and in 80–90% yield by controlled stereospecific hydrolysis using sodium hydroxide in aqueous pyridine. Reductive amination of 3β-hydroxy-5-androsten-17-one and 3-methoxy-3,5-androstadien-17-one () using ammonium acetate and sodium cyanohydridoborate (NaBH3CN) and a subsequent treatment with acid gave the amines and respectively, as a salt. The corresponding 17-imino compounds and were also isolated from the reaction mixtures when methanol was used as a solvent for the reaction. The 16α-hydroxyl compounds and and the 17β-amino compound were con- verted to the corresponding bromoacetyl derivatives, , , and , with bromoacetic acid and N,N'-dicyclohexylcarbodiimide. 相似文献
3.
Malcolm MacCoss Eung K. Ryu Tatsuo Matsushita 《Biochemical and biophysical research communications》1978,85(2):714-723
Recently, 1-β--arabinofuranosylcytosine-5′-diphosphate--1,2-dipalmitin (VIa) was reported to inhibit the growth of L51784 cells in mice and of human colon carcinoma HCT-15 cells, also in mice. This paper describes the synthesis of a single diastereomer by conversion of 1-β--arabinofuranosylcytosine 5′-monophosphate (II) to the nucleoside 5′-phosphomorpholidate (III), followed by reaction with -α-dipalmitoylphosphatidic acid (IV) to give 1-β--arabinofuranosylcytosine-5′-diphosphate--1,2-dipalmitin (V) in good yield. The separation of the product is described and its characterization by chromatography, elemental analysis, and spectroscopic methods. The lipophilic nature of V renders it insoluble in aqueous media and a method of sample preparation utilizing sonication techniques is described which provides a clear solution suitable for biological evaluation. In addition, the ability of V to inhibit the growth of L1210 cells and of mouse myeloma MPC 11 cells is desscribed and compared with 1-β--arabinofuranosylcytosine (I) and other lipophilic prodrugs of I. 相似文献
4.
A new polyhydroxysterol 1β,3β,5,6β-tetrahydroxy-5α-androstan-17-one () was isolated from the soft coral . The structure of was deduced from comparison of the spectral data with those of known 1β,3β,5α,6β-tetrahydroxysterols and confirmed by the synthesis starting from 1β,3β-dihydroxy-5,16-pregnadien-20-one () 相似文献
5.
The epididymis of adult rats metabolize 3H-testosterone by experiments . Thirty minutes after the injection of 100 μCi 3H-testosterone, some 10 per cent of the total radioactivity of the epididymis was found in the water-soluble fraction, whereas 90 per cent was found in the ether soluble fraction (free steroids). The free steroids were examined further and the following androgenic metabolites identified: (17β-hydroxy-4-androsten-3-one) 8, 9%, (4-androstene-3, 17-dione, 2,7%, (5α-androstane-3, 17-dione) 6,5%, (17β-hydroxy-5α-androstan-3-one) 47, 2%, (5α-androstane-3β, 17β-diol) 4, 4%, (5α-androstane-3α,17β-diol) 20, 8% and (3α-hydroxy-5α-androstan-3-one) 3,4%. The relative amount of each metabolite is given in per cent of total radioactivity in the ether soluble fraction. 相似文献
6.
4β,5-Epoxy-5β-androstane-3,17-dione (), 17β-hydroxy-4β,5-epoxy-5β-androstan-3-one () and 17β-acetoxy-4β,5-epoxy-5β-androstan-3-one () were treated with anhydrous hydrogen fluoride in pyridine (70% solution) at 55° and yielded the corresponding 4-en-4-ols e.g. 4-hydroxy-4-androstene-3, 17-dione ().As the reaction temperature was lowered each epoxide formed a second product which, at ?75°, was the major component of the reaction mixture and was identified as the 5α-fluoro-4α-ol derivative of the parent enone, e.g. 4α-hydroxy-5-fluoro-5α-androstane-3,17-dione (). These fluorohydrins are thermally unstable, losing hydrogen fluoride.The acetates of the fluorohydrins were also prepared, characterized, and shown to be more stable than the parent alcohols. 相似文献
7.
The synthesis of 4-ethenylidene-5α-androstane-3β, 17β-diol () and of 4-ethenylidene-5α-androstane-3,17-dione () is described. Compound is a competitive inhibitor of solubilized bovine microsomal adrenal Δ5-3β-hydroxysteroid dehydrogenase, with Ki =2.7μM, and is converted by the enzyme to the corresponding 3-ketone. Compound shown to irreversibly inactivate the enzyme in a time-dependent manner (). The substrate, dehydroepiandrosterone, protects against inactivation by compound . In contrast, compound is not oxidized at the 3-position by the 3β-(and 17β)-hydroxysteroid dehydrogenase from , but is oxidized at the 17-position. Nevertheless, the 4-ethenylidene-3,17-diketone () causes irreversible time-dependent inactivation () when incubated directly with this bacterial enzyme, acting as an affinity label. 相似文献
8.
Bojan Hamlin Jennings Sharon Martin Boudreau Beverly Braasch Cheryl Garganta 《Steroids》1982,39(4):371-380
Both the 5α, 6α- and 5β, 6β-dichloromethylene adducts ( and ) of 3β-acetoxy-5-androsten-17-one () are produced when the latter is exposed to dichlorocarbene generated from chloroform and base by Phase Transfer Catalysis using ultrasound as a means of agitation. The 1H NMR substituent effects of 5α, 6α- and 5β, 6β-dichloromethylene on the angular methyl groups (Zürcher values) are given. The 13C NMR spectra for both compounds are presented and discussed. 相似文献
9.
The conversion of a 5β-pregnan-3-one into a 3-thia-A-nor-pregnane is described. The single epimer, characterized as the 5β-isomer by nmr spectroscopy, was obtained.A previous report [1] from this laboratory described the synthesis of the epimeric 3-oxa-A-norpregnan-20-ones and from A-norprogesterone. Recently, the total synthesis of the related A-nor-3-thiaestra-1,-5(10)-diene derivative has been described [2]. Continuing interest [3] in A-ring-modified steroids as probes of drug-receptor interactions prompts this report of the preparation of the 3-thia-5β-A-norpregnan-20-one . 相似文献
10.
《Insect Biochemistry》1984,14(2):199-208
(OPFB)-heptafluorobutyrylester (HFB) derivatives and (MO)-trimethylsilylether (TMS) derivatives of non-ecdysteroid steroids were prepared from haemolymph extracts of last instar larvae of the fleshfly Sarcophaga bullata. Using a negative ion chemical ionization capillary gas chromatography-mass spectrometry (NCI/GC-MS) technique the following steroids could be identified: progesterone, testosterone, 5α-androstane-3β,17β-diol, 5β-androstane-3α,17β-diol, androst-5-ene-3β,17β-diol, androstenedione, 5α-dihydrotestosterone, 11-ketotestosterone, 11β-hydroxytestosterone, 17α-hydroxyprogesterone, 17α-hydroxyprogesterone, 17α,20β-dihydroxyprogesterone. Although the technique is very sensitive, estrogens could not be detected. These results suggest an active metabolism of progesterone and testosterone. 相似文献
11.
The dinoflagellate was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol. 相似文献
12.
A simple micro method for the estimation of urinary pregnanediol (5β-pregnane-3α,20α-diol) is described. Chloroform extracts of acid-hydrolyzed urine are assayed gas chromatographically at 235° using Gas Chrom Z coated with 0.5 gm % NPGA. Thirty urine specimens may be prepared for gas chromatography in 1.5 hr. The rate of hydrolysis of pregnanediol glucuronide is proportional to the concentration of acid, and the rate of decomposition of pregnanediol to the square of acid concentration. Normal pregnant women excreted a mean of pregnanediol in the first trimester, in the second, and in the third. During the luteal phase of the menstrual cycle the excretion of pregnanediol by normal women increased from to . 相似文献
13.
The epididymis of adult rats metabolizes 3H-testosterone by experiments . After incubation of slices from epididymal tissue for 2 hrs at 37°C, 8% of the total radioactivity was found in the water-soluble fraction, whereas 92% in the ether soluble fraction (free steroids). The free steroids were examined further and the following metabolites identified: (17β-hydroxy-4-androsten-3-one) 10,4%, (4-androstene-3,17-dione) 6,2%, (5α-androstane-3,17-dione) 7,3%, (17β-hydroxy-5α-androstane-3-one) 39,3%, (5α-androstane-3α,17β-diol) 22,7%, (5α-androstane-3β,17β-diol) 4,6% and androsterone(3α-hydroxy-5α-androstan-17-one) 8,9%. The relative amount of each metabolite is given in per cent of the total radioactivity in the ether soluble fraction. When segments (caput, corpus, cauda) of epididymis were incubated in the same way, differences in steroid metabolism were demonstrated. Characteristic for caput epididymidis was high formation of DHT (58,4%) and 3α-diol (23,5%). Corpus epididymidis showed lower formation of DHT (50,6%) and 3α-diol (12,7%), but an approximately 3 times higher formation of 5α-A-dione (12,0%) than caput (3,4%) and cauda (3,5%). Cauda epididymis showed the lowest formation of DHT (38,3%), whereas 3α-diol (29,1%) and androsterone (11,4%) formation were relatively high. The ratio between 17β-hydroxy metabolites (DHT and androstanediols) and 17-keto metabolites were much higher in the caput (8,8) than in the corpus (3,2) and cauda (3,6), indicating a higher 5α-reductase activity in this segment. 相似文献
14.
Amalia Slomiany Bronislaw L. Slomiany 《Biochemical and biophysical research communications》1980,93(3):770-775
A fucose-containingceramide octadekahexoside exhibiting blood-group (A+H) activity has been isolated from hog gastric mucosa. Based on the results of partial acid hydrolysis, sequential degradation with specific glycosidases, oxidation with periodate and chromium trioxide, and permethylation analysis, we propose that the carbohydrate chain of this fucolipid contains four branches. Two of the branches are terminated by βGall→4βGlcNAc, one by and one by . 相似文献
15.
Several cholesterol analogs structurally modified in nuclear substitutions were tested for sustaining the growth of the silkworm . 5α-Cholest-7-en-3β-ol, 5,7-cholestadien-3β-ol and cholesteryl acetate can replace cholesterol as sterol source for Considerably good growth was also obained with 5α-cholest-14-en-3β-ol and 5α-cholesta-6,8(14)-dien-3β-ol. Other sterols tested were either partially effective or ineffective as nutrients. 相似文献
16.
Antoine Pilven Marie-Lise Thieulant Bernadette Ducouret Suzanne Sampérez Pierre Jouan 《Steroids》1976,28(3):349-358
The and metabolism of by the male rat anterior pituitary was studied. A rapid and intensive conversion of 5α-androstane-3α,17β-diol into 5α-dihydrotestosterone was demonstrated, since following a 30 min. incubation time, 73 % of the recovered radioactivity were constituted by 5α-dihydrotestosterone. Studies on the subcellular distribution of steroids showed that 5α-dihydrotestosterone was the main steroid recovered except from the 105,000 × g pellet. From and experiments it was concluded that the transformation of 5α-dihydrotestosterone into 5α-androstane-3α,17β-diol was a reversible process, and that this last steroid could exert its biological action mainly 5α-dihydrotestosterone. 相似文献
17.
D.H. van den Eijnden D.H. Joziasse L. Dorland H. van Halbeek J.F.G. Vliegenthart K. Schmid 《Biochemical and biophysical research communications》1980,92(3):839-845
Partial sialylation of biantennary and triantennary glycopeptides of α1-acid glycoprotein using colostrum β-galactosideα(2→6) sialyltransferase followed by high resolution 1H-NMR spectroscopic analysis of the isolated products enabled the assignment of the branch as the most preferred substrate site for sialic acid attachment. The branch appeared to be much less preferred and the Galβ(1→4)GlcNAcβ(1→4)Manα(1→3)Man sequence of triantennary structures was of intermediate preference for the sialyltransferase. The specificity of the β-galactoside α(2→6) sialyltransferase is thus shown to extend to structural features beyond the terminal -acetyllactosamine units on the oligosaccharide chains of serum glycoproteins. 相似文献
18.
A novel sterol containing four hydroxy groups has been isolated from the soft coral Its structure, 5α-ergostane-3β, 5,6β,7β-tetrol (), has been deduced by spectroscopic methods and confirmed by comparison with a synthetic analog. 相似文献
19.
Makoto Ito Tatsuya Yamagata 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,801(3):381-387
The linkage of teleost skin keratan sulfate to protein was investigated. Afeter its exhaustive digestion with pronase, peptidokeratan sulfate was obtained with aspartic acid as the predominant amino acid. The N-terminal of the amino acid residues of the preparation was dansylated, and the carbohydrate-peptide linkage fragment was isolated, with the aid of fluorescence, by sequential digestion with Flavobacterium endo-β-galactosidase, β-galactosidase, β-N-acetylhexosaminidase and endo-β-N-acetylglucosaminidase D, followed by Bio-Gel p-4 column chromatography. The structure of the dansylated fragment thus obtained was identified dansylated asparaginyl . Treatment of the dansylated keratan sulfate peptide with almond glycopeptidase, which specially cleaves thet asparaginyl linkage in the glycoproteins, also showed asparaginyl linkage to be in the core region of this keratan sulfate. We conclude that teleost skin keratan sulfate is bound to protein via an N-glycosyl linkage between and asparagine. The keratan sulfate core apparently consist of trimannosyl-N,N′-diacetylchitobiose units, considering the specificity of endo-β-N-acetylglucosaminidase D. 相似文献
20.
The subcellular localization of 3α-hydroxysteroid dehydrogenase, the dependency of the rate of reaction on time, concentration of protein, cofactor requirements and the substrate stereospecificity were investigated in the adult rat brain. The conversion of 3-keto-5β-cholanoic-24-14C acid to lithocholic acid was shown to occur in the cytosol without added cofactors. Incubation of 14C labeled 3α,7α-dihydroxy-5β-cholanoic and 3α,12α-dihydroxy-5β-cholanoic acids with adult rat brain cell-free preparations resulted in the production of less polar metabolites identified as 3-keto-7α-hydroxy-5β-cholanoic and 3-keto-12α-hydroxy-5β-cholanoic acids by TLC, GLC combined with a radioactive monitoring detection system and by cocrystallization to constant specific activity. 相似文献