- Relative Reactivities and Mechanistic Aspects of the Reactions of Organic Halides with Alkali Metals in Alcohol Environments
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The relative reactivities of organic halides over wide concentration ranges have been determined with limited amounts of lithium, sodium, and potassium in 2-ethoxyethanol (1) at 0 deg C.Under these conditions the organometallics formed protonate to their hydrocarbons rather than undergo exchange, elimination, and simple or crossed coupling.In dilute solution in 1 the relative reactivities (r1/r2) of varied halides with lithium are essentially structure independent.However, as the concentrations of the halides increase, their relative reactivities become significantly different and depend on the total concentrations T (M) = 1X> + 2X>> of the organic halides.With lithium at increased halide concentrations (1) the reactivities are iodides > bromides > chlorides, (2) halides of lower molecular weight react more rapidly than their higher homologues, and (3) the reactivity orders of chlorides are (a) allyl > primary > secondary > tertiary > neopentyl, (b) 2-buten-1-yl > 1-buten-3-yl, (c) benzyl > phenyl, and (d) p-chlorotolyl > o-chlorotolyl > m-chlorotolyl.As examples, the relative reactivities of 1-chlorobutane/2-chloro-2-methylpropane (CT = 5.83 M), 3-chloropropene/1-bromobutane (CT = 4.60 M), bromobenzene/p-chlorotoluene (CT = 4.37 M), and benzyl chloride/chlorobenzene (CT = 4.02 M) are 6.71, 5.43, 24.1, and 22.1, respectively.Additions of aprotic solvents to 1-chlorobutane and 2-chloro-2-methylpropane in 1 decrease the relative reactivities of the halides.The effectiveness of cosolvents in lowering the relative reactivities of lithium with 1-chlorobutane and 2-chloro-2-methylbutane is tetrahydrofuran > dioxane ca. 2-ethoxyethanol (1) > cyclohexene ca. benzene.The relative reactivities of halides with sodium and with potassium in 1 at 0 deg C are also total halide concentration (CT) dependent.Under comparable concentrations the relative reactivity differences of halides are greater with lithium than sodium than potassium.The reactivities of halides under conditions of chemical control can be correlated with the ionization potentials of the alkali metals, and the kinetically controlling features of these systems are different from those with magnesium.The behavior of the alkali metals, the effects of concentration, and the roles of solvents on the reactivities of halides are discussed on the basis of (1) the active sites on the metal surfaces as modified by induction and (2) steric and electronic factors in the organic substrates.The kinetically controlled reactions of lithium with sp3 halides may be interpreted to invole formation of lithio organohalide radical anions (R.-X(1-), Li(1+)), electron transfer to the lithio radical anions on the metal surface, or unsymmetrical four-center carbanionic processes on the metal.In addition to incorporating an electron into the lowest unoccupied ? level of its C-X bond, an sp2 halide offers the possibility for kinetically controlling electron transfer into the ? system of its carbon-carbon double bond(s).
- Reynolds, J. L.,Doshi, D.,Shechter, H.
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Read Online
- Inhibitors of viral replication, their process of preparation and their therapeutical uses
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The present invention relates to compounds, their use in the treatment or the prevention of viral disorders, including HIV.
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(2014/05/06)
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- Fine-tuning the oxidative ability of persistent radicals: Electrochemical and computational studies of substituted 2-pyridylhydroxylamines
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N-tert-Butyl-N-2-pyridylhydroxylamines were synthesized from 2-halopyridines and 2-methyl-2-nitrosopropane using magnesium-halogen exchange. The use of Turbo Grignard generated the metallo-2-pyridyl intermediate more reliably than alkyllithium reagents. The hydroxylamines were characterized using NMR, electrochemistry, and density functional theory. Substitution of the pyridyl ring in the 3-, 4-, and 5-positions was used to vary the potential of the nitroxyl/oxoammonium redox couple by 0.95 V. DFT computations of the electrochemical properties agree with experiment and provide a toolset for the predictive design of pyridyl nitroxides.
- Bogart, Justin A.,Lee, Heui Beom,Boreen, Michael A.,Jun, Minsik,Schelter, Eric J.
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supporting information
p. 6344 - 6349
(2013/07/26)
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- Catalyst component, catalyst for olefin polymerization, and process for producing olefin polymer using catalyst
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A polymer having high catalyst activity, excellent hydrogen response, high stereoregularity and high yield can be obtained by polymerizing olefins in the presence of a catalyst for olefin polymerization comprising (A) a solid catalyst component containing magnesium, titanium, a halogen, and an electron donor compound, (B) an organoaluminum compound shown by the formula R6pAlQ3-p(R1R2N)m, and (C) an aminosilane compound shown by the formula (R3HN)nR4pSi(OR5)q.
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- MATERIAL FOR ORGANIC ELECTRO-OPTICAL DEVICE HAVING FLUORENE DERIVATIVE COMPOUND AND ORGANIC ELECTRO-OPTICAL DEVICE INCLUDING THE SAME
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The present invention relates to a material for an organic electro-optical device and an organic electro-optical device including the same. More particularly, the present invention relates to a material having thermal stability of a glass transition temperature of 120° C. or more and a thermal decomposition temperature of 450° C. or more, and being capable of providing an organic electro-optical device having high efficiency and a long life-span due to less crystallization and improved amorphous properties in a material for an organic electro-optical device. The material for an organic electro-optical device can be used singularly or as a host material in combination with a dopant, and includes an asymmetric fluorene derivative compound. An organic electro-optical device including the material for an organic electro-optical device is also provided.
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- PROCESS OF MAKING ALUMINUM ALKYLS
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The present invention generally relates to a new process of making a trialkyl aluminum compound in which at least one alkyl group is a primary alkyl derived from an internal olefin or alpha-olefin. The process employs an isomerization/hydroalumination catalyst.
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- Reactivity of individual organolithium aggregates: A RINMR study of n-butyllithium and 2-methoxy-6-(methoxymethyl)phenyllithium
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Low-temperature rapid injection NMR (RINMR) experiments were performed on two lithium reagents, n-butyllithium and 2-methoxy-6-(methoxymethyl)phenyllithium (5), with the goal of measuring the relative reactivity of the different aggregates (dimer, mixed dimer, and tetramer for n-BuLi, monomer and tetramer for 5) toward typical electrophiles. The reaction of the n-BuLi dimer with (trimethylsilyl)acetylene first forms the mixed dimer n-BuLi·Me3SiC≡CLi, which is about 1/60 as reactive as the n-BuLi homodimer. The tetramer does not react. In the deprotonation of (phenylthio)acetylene, the n-BuLi dimer was found to be 3.5 × 108 as reactive as the tetramer, and in the addition to p-diethylaminobenzaldehyde, the relative reactivity was at least 2 × 104. In the deprotonation of (p-tolylsulfonyl)acetylene, the monomer of 5 was at least 1014 times as reactive as the tetramer. These measurements show that the difference in reactivity between the lower and higher aggregates of organolithium reagents can be many orders of magnitude higher than all previous estimates. Copyright
- Jones, Amanda C.,Sanders, Aaron W.,Bevan, Martin J.,Reich, Hans J.
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p. 3492 - 3493
(2008/01/01)
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- Use of sulfur containing initiators for anionic polymerization of monomers
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An initiator is presented for anionically polymerizing monomers, to provide a functional head group on the polymer. A polymer having a functional head group derived from a sulfur containing anionic initiator, and optionally as additional functional group resulting from the use of a functional terminating reagent, coupling agent or linking agent is also provided. A method is presented for anionically polymerizing monomers comprising the step of polymerizing the monomers with a sulfur containing anionic initiator to provide a functional head group on the polymer. An elastomeric compound, comprising a functional polymer and filler is also described. Also provided is a tire having decreased rolling resistance resulting from a tire component containing a vulcanizable elastomeric compound.
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- METHOD FOR PRODUCING ALKYL LITHIUM COMPOUNDS AND ARYL LITHIUM COMPOUNDS BY MONITORING THE REACTION BY MEANS OF IR-SPECTROSCOPY
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The invention relates to a method for producing alkyl lithium compounds and aryl lithium compounds by reacting lithium metal with alkyl or aryl halogenides in a solvent, the concentration of the alkyl/aryl halogenide and the alkyl/aryl lithium compound being detected according to an in-line measurement in the reactor by means of IR spectroscopy, and an exact recognition of the end point of the dosing of the halogenide constituents being carried out by evaluation of the IR measurement. Said method enables an optimum reactive process and reaction yield. The identification of the respective concentration of the educt and the product is a reliable reactive process. The yield of the reaction is also optimised by determining the end point of the halogenide dosing, as is the purity of the product due to a lower concentration thereof during the reaction.
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Page/Page column 12-13; 13-14
(2008/06/13)
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- Novel processes for the preparation of (R)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol
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The present invention provides various processes for the preparation of (R)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol. These processes may be characterized by the following scheme:
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- METHOD FOR THE PRODUCTION OF ACETYLENE ALCOHOLS
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The invention relates to a method for producing acetylene alcohols of general formula (I), wherein R1, R2 can independently be identical or different and represent optionally substituted hydrogen, an optionally substituted saturated, monounsaturated or polyunsaturated C1-C30 alkyl radical, aryl radical, cycloalkylalkyl radical, or cycloalkyl radical, or a group of general formula (II), wherein R3, R4 can independently be identical or different and represent optionally substituted hydrogen or an optionally substituted saturated, monounsaturated, or polyunsaturated C1-C30 alkyl radical, aryl radical, cycloalkylalkyl radical, or cycloalkyl radical while the dashed line can represent an additional double bond. Said acetylene alcohols are produced by monoethynylating a ketone of general formula R1-CO-R2 by (a) reacting lithium with a C1-C10 alkyl halide, (b) introducing acetylene gas, and (c) adding the ketone.
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(2008/06/13)
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- Anthranilamides and methods of their use
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The present invention is related to anthranilamides of formula I, in which R(1) to R(7) have the meanings indicated herein, a process for their preparation, their use as medicaments, and pharmaceutical preparations containing them. The compounds act on the Kv1.5 potassium channel and inhibit a potassium current which is referred to as the ultra-rapidly activating delayed rectifier in the atrium of the human heart. The compounds are therefore suitable for use as novel antiarrhythmic agents for the treatment and prophylaxis of atrial arrhythmias (e.g., atrial fibrillation (AF) or atrial flutter).
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- RXR modulators with improved pharmacologic profile
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The present invention provides a novel class of RXR modulator compounds that exhibit an improved pharmacologic profile relative to the profile of previously studied RXR modulators, including those that share common structural features with the presently claimed modulators. The present invention also provides synthetic methods for preparing these compounds as well as pharmaceutical compositions incorporating these novel compounds and methods for the therapeutic use of such compounds and pharmaceutical compositions.
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- Cephalotaxane derivatives and process for their preparation
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The present invention concerns a new general process for asymetric hemisynthesis of harringtonines and their analogs, that are alcaloids used in chimiotherapy. This process comprises direct esterification of a natural cephalotaxine with an acylating compound constituted of a side chain precursor which backbone and fonctionalization are entirely preformed.
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- Bioactivated diagnostic imaging contrast agents
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The present invention relates to improved diagnostic agents for Magnetic Resonance Imaging and optical imaging. In particular, this invention relates to MRI and optical imaging agents that allow for the sensitive detection of a specific bloactivity within a tissue. These agents are prodrug contrast agents which are bioactivated in vivo in the presence of the specific bioactivity. This invention also relates to pharmaceutical compositions comprising these agents and to methods of using the agents and compositions comprising the agents.
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- Novel processes for the preparation or (R)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol
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The present invention provides various processes for the preparation of (R)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol. These processes may be characterized by the following scheme:
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- Process for the preparation of lamotrigine
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The invention provides a process for producing lamotrigine of formula (I): STR1 which process comprises subjecting a compound of formula (II): STR2 wherein R is CN or CONH2, in an organic solvent, to ultra violet or visible radiation and, when R is CN, to heat.
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- Process for preparing derivatives of the taxoid family
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The present invention relates to a novel process for preparing dialkoxy derivatives of the taxoid family by direct alkylation of the two positions 7 and 10 of deacetylbaccatin or derivatives thereof which are esterified in position 13.
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- Leukotriene antagonists for use in the treatment or prevention of alzheimer's disease
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This invention provides methods for the treatment or prevention of Alzheimer's disease which comprises administering to a mammal in need thereof an effective amount of a compound having activity as a leukotriene antagonist.
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- PROTEASE-BINDING COMPOUNDS AND METHODS OF USE
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Non-peptide, protease-binding compounds are described as useful in the detection, labelling, and inhibition of retroviral proteases. Aryl piperidinyl derivatives and other compounds related in structure have been found to be HIV-1 and HIV-2 protease-binding compounds.
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- SUBSTITUTED PHENYL PHENOL LEUKOTRIENE ANTAGONISTS
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Antagonists having a substituted phenyl phenol or a substituted phenolic biphenyl structure, and various derivatives thereof, are specific leukotriene antagonists. Their structures, use and synthesis are disclosed. Also, pharmaceutical formulations are disclosed for use in applications treating diseases or conditions characterized by excessive release of leukotriene B 4, one of the metabolites of arachidonic acid.The primary LTB 4 antagonistic structures are represented as: STR1
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- Radiohalogenation conjugate technology
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Compounds of the formulae, STR1 are provided where L is a linking group of the formula, STR2 is --Sn(n--C4 H9)3 or --Sn(CH3)3, HgCl or --N2+ ; R is hydrogen, methyl, mono-, di- or oligosaccharide; and R' is methyl. The compounds are site-specifically halogenated or radiohalogenated at the A group and coupled with macromolecules such as monoclonal antibodies, peptides or other proteins.
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- Sulfonic acid derivatives in the treatment of viral diseases
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Sulfonic acid stilbenes are disclosed which block the infection of cells by HSV, HIV and CMV.
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- N-ACYLAMINO ACID DERIVATIVES AND THEIR PHARMACEUTICAL COMPOSITIONS
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An N-acylamino acid derivative of the formula: STR1 wherein the substituents are herein defined or a salt thereof, which is useful as hypotensive drugs.
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- Novel extraction agents and novel propane diamides
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The invention relates to novel extracting agents and novel propane diamides, their use for the recovery of actinides and/or lanthanides and their preparation process. These extracting agents are constituted by propane diamides of formula: STR1 For example, the extracting agent can be 2-hexyl-N,N'-dimethyl-N,N'-dibutyl-propane diamide or 2-ethoxyethyl-N,N'-dimethyl-N,N'-dibutyl-propane diamide. They are more particularly used for the recovery of actinides and/or lanthanides present in the trivalent state in an acid aqueous solution, particularly in a nitric solution.
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- Hypoglycemic 5-substituted oxazolidine-2,4-diones
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Hypoglycemic 5-furyl and 5-thienyl derivatives of oxazolidine-2,4-dione and the pharmaceutically-acceptable salts thereof; certain 3-acylated derivatives thereof; and intermediates useful in the preparation of said compounds.
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- STERIC EFFECTS IN SYSNTHESIS - STERIC LIMITS TO THE ALKYLATION OF NITRILES AND CARBOXYLIC ACIDS
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The steric limits to the alkylation of aliphatic nitriles and carboxylic acids have been investigated in some detail.For the experimental conditions considered (ionization by i-Pr2NLi in THF followed by alkylation with RI/THF/HMPA) the most hindered nitriles R-CN and carboxylic acids R-CO2H have the same secondary alkyl group R=t-BuiPrCH-, but different tertiary, i.e.R=t-BuiPrEtC- or i-Pr3C- for RCN and R=Et2MeC for RCO2H.A comparison of the relative merits of alkylation of esters, carboxylic acids, and nitriles is considered.
- MacPhee, John-Anthony,Dubois, Jacques-Emile
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p. 775 - 778
(2007/10/02)
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- C-NITROSO COMPOUNDS-XXXV REACTION OF ORGANOMETALLIC COMPOUNDS WITH 1-CHLORO-1-NITROSO-2,2,6,6-TETRAMETHYLCYCLOHEXANE
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Reaction of Grignard reagents and organolithium compounds (RM) with the congested 1-chloro-1-nitroso-2,2,6,6-tetramethylcyclohexane 1 leads to the formation of significant amounts of the reduction product 2,2,6,6-tetramethylcyclohexanone oxime 3 (61-90percent) together with the corresponding oxime O-R ether 4 (0-11percent).Attack on nitrogen is unimportant as shown by very low yields of nitrone.Formation of the products is rationalised with a pathway involving transfer of an electron from RM to 1.This leads-after separation of MCl-to a radical pair consisting of R. and the relatively stable iminoxy radical 2 (Schemes 1 and 2).Combination of these radicals explains formation of oxime ether 4 and nitrone 5, while reaction of iminoxy radical 2 with excess of RM can give oxime 3.Reactive radicals R. (i.e.Me,Ph, and to a minor extent n-Bu) are furthermore capable of abstracting hydrogen from the solvent (diethyl ether, toluene, or cumene), and the solvent derived radicals can also combine with 2 on oxygen, under formation of oxime ether (26percent of 6a).The corresponding benzyl- and cumyl ethers 6b and 6c are only formed in trace amounts because dimerisation of benzyl radicals (7percent) and cumyl radicals (22percent) is favoured.
- Schenk, C.,de Boer, Th. J.
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p. 1843 - 1846
(2007/10/02)
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- Thiazine derivatives
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Anti-inflammatory, analgesic, anti-rheumatic and anti-thrombotic thienothiazine derivatives having the formula STR1 wherein A together with the two carbon atoms forms the group STR2 and the dotted line indicates the double bond present in the first and last thieno structures above, R1 is lower alkyl, R2 is the radical of an aromatic heterocycle with 1 to 4 hetero atoms optionally substituted by one or two lower alkyl groups, or a phenyl radical optionally substituted by halogen, hydroxy, lower alkyl, trifluoromethyl or lower alkoxy, R3 is halogen and R3' is hydrogen or halogen, and pharmaceutically acceptable salts thereof are described.
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- Prostaglandin analogues
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New trans-Δ2 -prostaglandins of the formula STR1 (wherein R1 represents a hydrogen atom or a straight- or branched-chain alkyl group containing from 1 to 10 carbon atoms, R2 represents a 1,1-dimethyl-pentyl group or a 2-ethylheptyl group, the wavy line indicates attachment of the depicted group in α-configuration or racemic form consisting of equimolecular mixtures of α-configuration and β-configuration and the C2 -C3 and C13 -C14 double bonds are trans), which are useful for the treatment of hypertension, contraception menstrual regulation.
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- Polyprenyl derivatives
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Polyprenyl derivatives having the formula STR1 in which R1 and R2 may be the same or different and each represents hydrogen atom, hydroxyl group, an alkoxy group having 1-8 carbon atoms, an aliphatic acyloxy group having 2-18 carbon atoms, an aromatic acyloxy group or an araliphatic acyloxy group having 2-3 carbon atoms in the aliphatic acyl moiety, R3 represents hydrogen atom, an alkyl group having 1-8 carbon atoms, an aliphatic acyl group having 2-18 carbon atoms, an aromatic acyl group or an araliphatic acyl group having 2-3 carbon atoms in the aliphatic acyl moiety, n is an integer of 1-4 and, when n is an integer of 2-4, R2 's may be the same or different; provided that, when n is 1 or 2, at least one of R1 and R2 's is hydroxyl group, an alkoxy group, an aliphatic acyloxy group, an aromatic acyloxy group or an araliphatic acyloxy group. These derivatives are useful as medicines for treating peptic ulcer.
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- 15-Cycloalkyl-prostaglandins
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15-Cycloalkyl-prostaglandins of the formula:- STR1 wherein A represents a grouping of the formula:- STR2 X represents ethylene of cis-vinylene, Y represents ethylene or trans-vinylene, B represents ethylene or trans-vinylene, R represents hydrogen or alkyl of 1 through 4 carbon atoms, R1 represents cycloalkyl of 4 through 7 carbon atoms, and R2 represents hydrogen or alkyl of 1 through 12 carbon atoms, are new compounds possessing the useful pharmacological properties typical of prostaglandins; they are of especial interest in the inhibition of blood platelet aggregation.
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- Alkali metal-containing, organometallic products
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An alkali metal-containing, organometallic product, which is hydrocarbon-soluble, is prepared by reacting an organo-alkali metal reactant in which the alkali metal atom is bonded to a carbon atom, e.g. cyclohexyl-lithium, with a di(organooxy)-alkaline earth metal reactant, e.g. di-n-butoxy-magnesium, in an organic solvent at about -20° to +120°C. The organo-alkali metal reactant can be prepared by reacting an organo halide with an alkali metal, and this can be done in situ, i.e. in the presence of the di(organooxy)-alkaline earth metal reactant. The organometallic product has approximately the same chemical reactivity as the organo-alkali metal reactant from which it is prepared, but is more soluble in hydrocarbon solvents.
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