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1.
Alkyl- and Aryl-acyl Derivatives of Geminal Dithiols The reaction of α-halosulfides 3 with alkali salts of thiocarboxylic acids 4 or α-haloalkyl-acyl sulfides 7 with alkyl and aryl mercaptans 6 yields alkyl- or aryl-acyl derivatives of methane-, ethane- and propane-1,1-dithiol 5 .  相似文献   

2.
Synthesis of 2,2a,3,4-Tetrahydroazeto[1,2-d]benzo[b]-1,4-oxazine-2,4-diones The 1-(2-hydroxyaryl)-4-oxoazetidine-2-carboxylic acids 7c, 7d and 10 react with dicyclohexylcarbodiimide to give the title compounds 11, 12 and 13 . Compound 13 can also be obtained by nitration of 12 . The starting materials 7c , 7d and 10 are synthesized from the l-aryl-4-oxoazetidine-2,2-dicarboxylates 4a and 4b , which are available from 1 by a method analogous to that described by Sheehan2) or via 8 and 9 .  相似文献   

3.
(4R,5S)/(4S,5R)-4,5-Bis(4-hydroxyphenyl)-2-imidazolines bearing 2,2'-H (3a), 2,2'-Cl (3b), 2,2',6-Cl (3c), and 2,2'-F (3d) substituents in the aromatic rings were C2-alkylated (5a-i), N-alkylated (7, 7a-c), and N,N'-dialkylated (9a-c). The synthesis started from the diastereomerically pure (1R,2S)/(1S,2R)-1,2-diamino-1,2-bis(4-methoxyphenyl)ethanes 1a-d, which were cyclized to the imidazolines 2a-d and 4a-i with triethylorthoesters or iminoethers. Ether cleavage with BBr(3) yielded the (4R,5S)/(4S,5R)-4,5-bis(4-hydroxyphenyl)-2-imidazolines 3a-d and 5a-i. The N-alkylation and N,N'-dialkylation of 2b, employed for obtaining 7a-c and 9a-c, were performed prior to the ether cleavage with alkyl iodine in dry THF. By use of HPLC, the influence of the substitution patterns in the aromatic rings and alkyl chains at the C2- or N-atoms on the hydrolysis rate of the imidazolines was studied under in vitro conditions. It appeared that only imidazolines with C2- or N-alkyl substituents show sufficient stability to interact as heterocycles with the estrogen receptor (ER). The resulting gene activation was monitored in a luciferase assay using ERalpha-positive MCF-7-2a breast cancer cells stably transfected with the plasmid ERE(wtc)luc. It is interesting to note that C2-alkylation led to a strong reduction or even a complete loss of activity whereas N-alkylation improved the estrogenic profile. The (4R,5S)/(4S,5R)-N-ethyl-4,5-bis(2-chloro-4-hydroxyphenyl)-2-imidazoline 7b has proven to be the most active compound in this structure-activity relationship study (EC(50) = 0.015 microM).  相似文献   

4.
The metabolism and cytotoxicity of benzyl 1,2,3,4,4-pentachlorobuta-1,3-dienyl sulfide (1) and benzyl 2-chloro-1,1,2-trifluoroethyl sulfide (2) were studied as an alternative test of the hypothesis that the toxicity of the cysteine S-conjugates S-(pentachlorobutadienyl)-L-cysteine and S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine is associated with their metabolism to unstable thiols; the expectation was that the benzyl sulfides 1 and 2 would undergo cytochrome P-450 dependent benzylic hydroxylation and that the intermediate hemimercaptals would eliminate unstable, cytotoxic thiols. This expectation was realized: 1 and 2 were cytotoxic in isolated rat hepatocytes. The cytotoxicity of 1 was greater in hepatocytes from phenobarbital-treated rats compared with control rats and in male than in female rats and was inhibited by carbon monoxide and 2-(N,N-diethylamino)ethyl 2,2-diphenylvalerate HCl (SKF 525-A). Benzyl sulfides 1 and 2 were metabolized to benzaldehyde by rat hepatic microsomal fractions and by a purified, reconstituted cytochrome P-450PB-B system. Benzaldehyde was not cytotoxic. These results provide support for the hypothesis that benzyl sulfides 1 and 2 and the corresponding cysteine S-conjugates yield unstable thiols, which may give rise to acylating agents or to stable, but toxic, terminal products that are responsible for the cytotoxic effects of the benzyl sulfides and cysteine S-conjugates.  相似文献   

5.
Warfarin-Analogous 1,2-Oxathiolane Derivatives 3-[3-Oxo-1-(4-chlorophenyl)butyl]-5,5-dimethyl-1,2-oxathiolan-4-one 2,2-dioxide which is structurally related to warfarin has been prepared and investigated by i.r., n.m.r. and mass spectrometry.  相似文献   

6.
The reaction of-(indolyl-3)-alkyl bromides with sodium thiosulfate gave Bunte salts (sodium indolylalkyl thiosulfates) which were converted into disulfides by the action of alkali. These were reduced with lithium aluminum hydride to mercaptans which then were converted by the action of methyl iodide into sulfides and these into sulfonium salts. A chemotherapeutic investigation showed the Bunte salts to have weak tuberculo static activity.Translated from Khimiko-Farmatsevticheskii Zhurnal, No. 1, pp. 4–6, January, 1967.  相似文献   

7.
The preparation and analgesic activities of a series of the entitled compounds (5-22) and the optical isomers of the 1-cyclohexyl derivative 5 are described. Reactions of N,N-bis(2-chloroethyl)-1,2-diphenylethylamine (3) with ammonia and primary amines gave N-(1,2-diphenylethyl)piperazine (4) and N1-substituted derivatives (5-20, 22), respectively. The alkylation of 4 afforded 12-21. Compounds 5-18 and 22 were also obtained by the reactions of 1,2-diphenylethylamine (23) and N-substituted 2,2'-dichlorodiethylamine. Racemate 5 was resolved with (+)- or (-)-2'-nitrotartranilic acid into its optical isomers [(+)-5 and (-)-5], and the absolute configuration of (+)-5 was determined to be S configuration by the synthesis and optical rotatory dispersion measurements. The most active members in this series of compounds were 5-7, which were approximately as potent as (-)-morphine. In the case of 5, the more potent enantiomer (S)-(+)-5 has the opposite configuration to that of (-)-N,N-dimethyl-1,2-diphenylethylamine (Spa) or (-)-morphine with respect to the (C-9) asymmetric center and belongs to a new series of compounds having potent analgesic activity.  相似文献   

8.
The reaction of 2,4-dihydroxypyridine (2) with 3,4-epoxy-3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (1) yielded the 4-[(1,2-dihydro-2-oxo-4-pyridyl)oxy] compound 3a, accompanied by small amounts of the isomeric 4-(1,2-dihydro-4-hydroxy-2-oxo-1-pyridyl) compound 4. This could also be prepared by hydrogenation of the benzyloxy derivative 5. Reaction of 3,6-pyridazinediol (10) with 1 (R = CN) gave the 4-[(1,6-dihydro-6-oxo-3-pyridazinyl)oxy] compound 11a, which in turn rearranged on heating with NaH in DMSO into the 4-(1,6-dihydro-3-hydroxy-6-oxo-1-pyridazinyl) compound 12. A series of 6-substituted analogues (R = CO2Me, CSNH2, NO2, Br) of 3a and 11a were synthesized. N-Alkylation led to compounds 14a-c (R = Me, Et, CHMe2). The 4-heterocyclyloxychromenes 9 and 16a were obtained by alkaline hydrolysis of their 3-camphorsulfonates. The racemic pyridazinyloxy compounds 11a and 14a could be resolved via their diastereomeric camphorsulfonates or camphanates. The differences between the 4-heterocyclyloxychromanols and the isomeric N-substituted compounds 4 and 12 were elucidated in the course of extensive NMR investigations. While in DMSO the former appeared to be conformationally flexible molecules the latter were rigid. All compounds were tested for oral antihypertensive activity in spontaneously hypertensive rats, using doses of 1 mg/kg. High and long lasting activities were found for the pyridyloxy compounds 3a and 3d, the pyridazinyloxy compound 11a, and its N-alkylation products, as well as for the 3S,4R-enantiomers 20a and 22a. (-)-(3S,4R)-3,4-Dihydro-4-[(1,6-dihydro-1-methyl-6-oxo-3- pyridazinyl)oxy]-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (22a) was selected for further development.  相似文献   

9.
Cytochrome P450-dependent oxidation and glutathione (GSH)-dependent conjugation are the primary routes of metabolism of haloalkanes. Using rat liver microsomes and cytosol, we investigated the metabolism of two halopropanes found on the U.S. Environmental Protection Agency Contaminant Candidate List, 1,3-dichloropropane (1,3-DCP) and 2,2-dichloropropane (2,2-DCP). An automated headspace technique using gas chromatography was developed to determine rates of metabolism. Additional dihaloalkanes (1,2-dichloroethane, 1,2-dichloropropane, 1,4-dichlorobutane, 1,2-dibromoethane, 1,2-dibromopropane, 1,4-dibromobutane) were evaluated to assess structure-activity relationships. In general, brominated dihaloalkanes were eliminated from rat cytosol faster than chlorinated dihaloalkanes, reflecting the expected halide order of reactivity (Br > Cl). Furthermore, the rate of GSH conjugation was proportional to alpha,omega-haloalkane chain length. The clearance of 1,3-DCP via the GSH conjugation pathway (1.6 x 10(-4) l/h/mg cytosol protein) was minor relative to the P450 pathway (2.8 x 10(-2) l/h/mg microsomal protein). In contrast, we did not observe metabolism of 2,2-DCP via the GSH-dependent conjugation pathway and observed only a minor level of clearance via the P450 pathway (7 x 10(-4) l/h/mg microsomal protein). Neither compound was mutagenic in various strains of Salmonella, including those containing GSTT1-1, indicating that GSTT1-1 does not metabolize 1,3-DCP or 2,2-DCP to mutagens. Analysis of the reaction products of 1,3-DCP and GSH in cytosol by liquid chromatography/mass spectrometry revealed significant production of S-(3-chloropropyl) glutathione conjugate, indicating that the conjugate half-mustard does not rearrange to form a sulfonium ion, as typically occurs with vicinal dihaloalkanes.  相似文献   

10.
Protein Binding Determined by Continuous Ultrafiltration, IV: Protein Bindung of Anticoagulant 1,2-Benzoxathiines The binding of three 1,2-benzoxathiines to human serum albumin has been investigated. The compound 3-(3-oxo-1-phenylbutyl)-1,2-benzoxathiin-4(3H)-one 2,2-dioxide (1) and its 4-methoxyphenyl analog 2 are bound in the same order of magnitude as warfarin. The binding of the 3,4-dichlorophenyl analog 3 is about tenfold stronger than that of usual anticoagulants.  相似文献   

11.
T S?awik 《Die Pharmazie》1991,46(11):777-780
In the search for pharmacological active new derivatives of 1,2-benzisothiazolin-3-on amides of (3-oxo-1,2-benzisothiazolin-2-yl)acetic acid and 3-(3-oxo-1,2-benzisothiazolin-2-yl)propionic acid were obtained. In the reaction of these amides with formaldehyde and various second aryl amines the title compounds are formed. Morpholinmethylamide of (3-oxo-1,2-benzisothiazolin-2-yl)acetic acid showed activity against Trichomonas vaginalis. In the reaction of ethyl esters of (3-oxo-1,2-benzisothiazolin-2-yl) acetic- and -propionic acids with hydrazine hydrate products of ring-opening of isothiazole-2,2'-dithio-bis [N- (ethoxycarbonylmethyl)benzamide] and 2,2'-dithio-bis[N-(ethoxycarbonylethyl)benzamide are formed.  相似文献   

12.
The following complexes of type [PtCl(R)(ACRAMTU)](NO3)2 (ACRAMTU = 1-[2-(acridin-9-ylamino)ethyl]-1,3-dimethylthiourea)), derived from prototype 1 (with R = ethane-1,2-diamine), were synthesized: 2 (with R = (1R,2R)-1,2-diaminocyclohexane), 3 (with R = propane-1,3-diamine), 4 (with R = N1,N1,N2,N2-tetramethylethane-1,2-diamine), and 5 (with R = 2,2'-bipyridine). The DNA sequence specificity of the conjugates and their antiproliferative potential in HL-60 and H460 cells were investigated. Conjugate 3 showed the strongest non-cisplatin-type DNA damage in polymerase stop assays and superior cell kill efficacy in H460 lung cancer (IC50 = 70 nM).  相似文献   

13.
The following 5-substituted 2,4-dimethoxypyrimidines were synthesized: 5-(2,2,2-trichloro-1-hydroxyethyl), 5-(2,2,2-trichloro-1-fluoroethyl),5-(2,2-dichloro-1-fluorovinyl) (5), and 5-(perfluoropropen-1-yl) (a mixture of E and Z isomers, 6 and 7). Demethylation of 5 gave 5-(2,2-dichloro-1-fluorovinyl)uracil, and demethylation of the mixture of 6 and 7 gave some pure (E)-5-(perfluoropropen-1-yl)uracil. Compound 5 was converted into its 2'-deoxyribonucleoside (12) and its alpha-anomer by standard procedures. 2'-Deoxy-3,5-dilithio-3',5'-O-bis(trimethylsilyl)uridine was reacted with the appropriate fluoroalkene to give the following 5-substituted 2'-deoxyuridines in low yield (6-24%): 5-(2-chloro-1,2-difluorovinyl) (a mixture of E and Z isomers, 15 and 16, which were separated on a small scale), 5-(perfluoropropen-1-yl), 5-(perfluorocyclohexen-1-yl), and 5-(perfluorocyclopenten-1-yl). In these reactions, 2'-deoxy-5-(trimethylsilyl)uridine and 2'-deoxyuridine were also formed. The 5-substituted 2'-deoxyuridines were tested for activity against herpes simplex virus type 1. Compound 12 and the mixture of 15 and 16 had an ID50 of 20-26 micrograms/mL in Vero cells. The activity of the mixture resided in one isomer, which by analogY with the corresponding (Z)- and (E)-5-(2-bromovinyl)-2'-deoxyuridines was concluded to be the Z isomer (16).  相似文献   

14.
Rearrangement of Dihydroisoquinolines, XXXVIII: Behavior of 1,2-Dihydroisoquinolines with Bulky C-1-Substituents towards Acids The 1,2-dihydroisoquinolines 2a-2d , obtained from the iminium salts 1a-1d by reduction with LiAlH4, are heated with dilute acids. The dihydroisoquinolines 2a and 2b rearrange with yields of 44% to 3a and 3b, 2c with a yield of 17% to 3c. Compound 2d does not rearrange, 70% of it are recovered. As an elimination product of the reaction of 2b with 0.1N HCl, 2,2′-ethane- 1,2-diylbisnaphthalene (12) was found which probably is a recombination product of β-naphthylmethyl radicals.  相似文献   

15.
16.
The first chemical synthesis of 2-aminoimidazo[1,2-a]-s-triazin-4-one (8), the corresponding nucleoside and nucleotide, and certain related derivatives of a new class of purine analogues containing a bridgehead nitrogen atom is described. Condensation of 2-amino-4-chloro-6-hydroxy-s-triazine (2) with aminoacetaldehyde dimethyl acetal followed by the ring annulation gave the guanine analogue 8. A similar ring annulation of 4-(2,2-dimethoxyethylamino)-s-triazine-2,6-dione (5) gave imidazo[1,2-a]-s-triazine-4,6-dione (9). Direct glycosylation of the trimethylsilyl derivative of 8 with 1-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose in the presence of stannic chloride, followed by debenzoylation, gave the guanosine analogue 2-amino-8-(beta-D-ribofuranosyl)imidazo[1,2-a]-s-triazin-4-one (12b), which on deamination gave the xanthosine analogue 13. Phosphorylation of 12b gave 2-amino-8-(beta-D-ribofuranosyl)imidazo[1,2-a]-s-triazin-4-one 5'-monophosphate (II). The anomeric configuration has been determined unequivocally by using NMR of the 2',3'-O-isopropylidene derivate 10 and the site of ribosylation has been established by using 13C NMR spectroscopy. These compounds were tested against type 1 herpes, type 13 rhino, and type 3 parainfluenza viruses in tissue culture. Moderate rhinovirus activity was observed for several compounds at nontoxic dosage levels.  相似文献   

17.
Blood levels of three aryldihydro-s-triazines in rats were followed: 4,6-diamino-1,2-dihydro-2,2-dimethyl-1-phenyl-s-triazine (I), the prototype of the series; 4,6-diamino-1-(3,4-dichlorophenyl)-1,2-dihydro-2,2-dimethyl-s-triazine (II); and N-(m-tolyl)-p-(4,6-diamino-1,2-dihydro-2,2-dimethyl-s-triazin-1-yl)hydrocinnamide (III). The blood profiles obtained provide substantial evidence that III, but not II, was precipitated in the peritoneal cavity where it was injected. Precipitation after intraperitoneal injection may explain why III and similar triazines with long nonpolar chains have been reported to be more active against intraperitoneal Walker 256 tumor than is II, even though the latter compound is a far more potent inhibitor of Walker 256 dihydrofolate reductase and of tumor cell cultures in vitro. Precipitation in the peritoneal cavity also may be involved in the difficulty of obtaining the toxicity-free antineoplastic activity expected from certain aryldihydrotriazines selectively inhibiting neoplastic dihydrofolate reductase.  相似文献   

18.
Trichloroethylene (TCE), a major environmental pollutant, is activated to mutagenic and nephrotoxic intermediates through a glutathione (GSH) conjugation pathway. Three product isomers of GSH-TCE conjugation, having potentially different toxicities, are theoretically possible: cis- or trans-S-(1, 2-dichlorovinyl)glutathione (cis- or trans-1,2-DCVG, respectively) or 2,2-DCVG. This study involved application of ab initio molecular orbital theory to computing potential energy profiles (PEPs) and predicting product outcome of the reaction of CH3S- with TCE as a model for GSH-TCE conjugation in biological systems. A goal of this study was to determine the extent to which a body of chemical knowledge pertaining to nucleophilic vinylic substitution (SNV) reactions, of which the GSH-TCE conjugation is a representative example, is relevant to this biological conjugation problem. PEPs were computed for all studied species at the HF/6-31+G level of theory; electron correlation effects were estimated at the MP2/6-31+G and MP4/6-31+G levels, and the influence of solvation was estimated using the PS-GVB solvation model. Multiple proposed reaction pathways were considered, including conjugation at the C1 or C2 site on TCE, by in-plane (sigma) or out-of-plane (pi) approach of the nucleophile. Some aspects of the MP2 and HF PEPs were found to differ significantly. However, on the basis of comparison of activation barriers, calculations at all levels of theory predict preference for C2 conjugation over C1 conjugation and formation of the trans-1,2-DCVM product over the cis-1,2-DCVM product. These predictions are consistent with GSH-TCE conjugation results from in vivo experiments. In contrast, relative product energies appear to be a poor indicator of the product outcome for this system. Hence, theoretical consideration of the reaction chemistry in the vicinity of the site of nucleophilic addition appears to be necessary and sufficient to predict the outcome of the enzyme-mediated GSH-TCE conjugation.  相似文献   

19.
海洋细菌Bacillus sp.次生代谢产物的分离与鉴定   总被引:1,自引:0,他引:1  
目的研究1株海洋细菌Bacillus sp.(No.DY1979)的次生代谢产物。方法采用各种色谱手段进行分离和纯化,根据各种光谱技术对单体化合物进行结构鉴定。结果分得12个化合物,分别鉴定为2,2′-二硫代二苯并噻唑(2,2′-dibenzothiazolyl disulfide,1)、2(3H)-苯并噻唑酮(2(3H)-benzothiazolone,2)、环(甘-脯)二肽(cyclo(Gly-Pro),3)、环(亮-脯)二肽(cyclo(Leu-Pro),4)、环(甘-丙)二肽(cyclo(Gly-Ala),5)、色氨酸(tryptophan,6)、1,2,3,4-四氢-3-羧基-2-卡波林(1,2,3,4-tetrahydro-3-carboxy-2-carboline,7)、胸腺嘧啶(thymine,8)、尿嘧啶(uracil,9)、苯乙酸(phenylace-tic acid,10)、邻苯二甲酸二异丁酯(1,2-benzenedicarboxylic acid diisobutyl ester,11)、邻苯二甲酸二正丁酯(1,2-benzenedicarboxylic acid dibutyl ester,12)。结论化合物1、2为含硫含氮的杂环类化合物,化合物1为细菌中首次分离,化合物2曾从另一株海洋细菌中分离得到;化合物3~9为含氮成分,其中化合物3~5为常见的细菌代谢产物环二肽,化合物6、7属氨基酸及其衍生物。  相似文献   

20.
A number of substituted diphenylsulfides and sulfones (4-11) and 2,2'-disubstituted-5,5'-dibenzimidazolyl sulfides and sulphones (12-19) have been synthesized starting from 5-chloro-2-nitroacetanilide and (3) 4,4'-dichlorodiphenyl sulfone (9), respectively. Among the compounds tested against Ancylostoma ceylanicum in hamsters and Hymenolepis nana in rats and mice, 14, 15, 18 and 19 removed 100% of the worms at an oral dose of 25 mg/kg X 1 to 250 mg/kg X 3. Some of the compounds were tested for their blood schizontocidal activity against Plasmodium berghei in mice but none showed any activity up to an oral dose of 10 mg/kg given for 6 days.  相似文献   

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