225 results about "Tetrahydrothiophene" patented technology

There are provided a liquid crystalline compound having a large negative Deltaepsilon, low viscosity, a large K33 / K11 value, a small Deltaepsilon / epsilonL and mutually excellent solubility even at extremely low temperature; a liquid crystal composition prepared from a liquid crystalline compound; and a liquid crystal display device fabricated from such a liquid crystal composition. The liquid crystalline compound of the present invention is a liquid crystalline compound represented by the following general formula (1): where, R<1 >represents hydrogen, fluorine, an alkyl group having 1 to 15 carbon atoms, or an alkenyl group having 2 to 15 carbon atoms; each of rings A<1>, A<2>, and A<3 >independently represents trans-1,4-cyclohexylene group, 1,4-cyclohexenylene group, trans-1,4-silacyclohexylene group, 1,4-phenylenegroup, 2,3-difluoro-1,4-phenylene group, 2-fluoro-1,4-phenylene group, 3-fluoro-1,4-phenylene group, pyrimidine-2,5-diyl group, pyridine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, tetrahydropyrane-2,5-diyl group, 1,3-dithiane-2,5-diyl group, or tetrahydrothiopyrane-2,5-diyl group; X<1 >represents hydrogen or fluorine; Y<1 >represents hydrogen or an alkyl group having 1 to 15 carbon atoms; 1 represents an integer from 1 to 10; and each of m and n independently represents 0 or 1.

The invention relates to a research and control method of impurity B control method in clopidogrel, the method comprises the following steps: (1) preparing a batch or multiple batches of 2-thiophene ethylamine; (2) measuring the 3-thiophene ethylamine in (1) by a GC method; (3) selecting 2-thiophene ethylamine with 3-thiophene ethylamine content not more than 0.40% based on the step (2) as initial materials: (4) obtaining the clopidogrel with less impurity B, adopting the 2-thiophene ethylamine in the step (3) by the preparation of 2-thiophene ethyl methylene amine and the preparation of 4, 5, 6, 7-tetrahydrothieno[3, 2-c]pyridine.

A method for the prevention of diseases caused by thrombus or embolus. The method is to separately administer 2-acetoxy-5-(α-cyclopropylcarbonyl-2-fluorobenzyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridine or a pharmaceutically acceptable salt thereof, and aspirin, in their pharmacologically effective amounts, to a warm-blooded animal.

The green refrigerant for small commercial refrigerator includes propane 54 wt%, isobutane R600a 45.5 wt% and tetrahydrothiophene THT 0.5 wt% to replace R134a; or includes propane 61 wt%, isobutane R600a 38.5 wt% and tetrahydrothiophene THT 0.5 wt% to replace R12. The present invention has refrigerating performance similar to that of R134a and R12, but has no destruction on ozone layer and greenhouse effect similar to CO2. The green refrigerant has simple mixing process, low consumption, low cost only 1 / 20 that of R134a, easily detected leakage and safety for use in small refrigerator.

The invention discloses a new preparation method of 2-methoxy-5-(alpha-cyclopropyl carbonyl-2-fluorobenzyl)-4, 5, 6, 7-tetrahydrothiophene [3, 2-c] pyridine, which only needs to one step that condenses 2-methoxy-4, 5, 6, 7-tetrahydrothiophene [3, 2-c] pyridine and alpha-halogenated p-fluorine benzyl cyclopropyl ketone to obtain targe product, with mild reaction conditions, non low temperature demand, non explosive material, high yield, low cost and high efficiency. The invention is suitable for large-scale industrial production.

The green additive for welding and cutting natural gas consists of ethanol 5-10 wt%, 2-hexanol 5-10 wt%, 2-hexanone 5-10 wt%, limonene 10-15 wt%, organoplatinum 0.02-0.08 wt%, and C5-C7 isoalkane for the rest. It is liquid with high oil solubility, low boiling point and high solubility in natural gas, and may be added into liquid one gaseous natural gas in any ratio. It is non-toxic and environment friendly, and can raise the combustion temperature of natural gas greatly to 3450 deg.c. In addition, it can lower the use cost of natural gas obviously.

The invention relates to hydrogenated pyridine derivates of 2-acetoxy-5-(Alpha-cyclopropyl carbonyl-2-fluorobenzyl)-4, 5, 6, 7-tetrahydrothiophene-[3, 2-C] pyridine as well as a preparation method of salt thereof. The method is to prepare two key intermediates of an Alpha-cyclopropyl carbonyl-2-fluorobenzyl halogen 2 (wherein, X=F, CL, Br and I) and a 2-oxygen-2, 4, 5, 6, 7, 7 Alpha-hexahydrothiophene-[3, 2-C] pyridine salt 3 (wherein, HA=HCL, H2SO4, HBr, HI, etc.), and to obtain the target product by esterifying products acquired through condensing the two key intermediates with acetic anhydride. The target product and the required acid addition salt are added with the needed crystal seed for obtaining crystals with a single crystal form in the process of crystallization.

A process for the preparation of clopidogrel (1) by reaction of the N,N′-bis-4,5,6,7-tetrahydro-[3,2-c]-thienopyridyl methane (12) with (R)-2-chlorophenylacetic acid derivatives of formula (13) in which X and R have the meanings as indicated in the disclosure.

A method for manufacturing (R)-tetrahydrothiophene-3-ol denoted by formula (II):by bioconversion of tetrahydrothiophene-3-one denoted by formula (I):to (R)-tetrahydrothiophene-3-ol denoted by formula (II). It comprises the steps of: (A) incubating the tetrahydrothiophene-3-one denoted by formula (I) in the presence of a strain, or a preparation of a cultured cell thereof, belonging to Penicillium, Aspergillus, or Streptomyces that is capable of said bioconversion; and (B) collecting the (R)-tetrahydrothiophene-3-ol denoted by formula (II) from incubated solution. A method for crystallization of optically active tetrahydrothiophene-3-ol of improved optical purity, characterized by maintaining a solution comprising optically active tetrahydrothiophene-3-ol and organic solvent at equal to or lower than 1° C. to cause optically active tetrahydrothiophene-3-ol to crystallize from said solution, or characterized by adding optically active tetrahydrothiophene-3-ol dropwise to organic solvent at a solution temperature of equal to or lower than 1° C. to cause optically active tetrahydro thiophene-3-ol to crystallize.

The invention provides an environment-friendly chlorofluorocarbon-free refrigerant and a preparation method thereof. The refrigerant is prepared from propane, propylene, cyclobutane, 2,3,3,3-tetrafluoropropene, trans-1,3,3,3-tetrafluoropropene, trifluoromethyl iodide, pentafluoromethyl iodide, difluoromethane, tetrahydrothiophene, liquid carbon dioxide and cryogenic lubricant. The refrigerant has the beneficial effects that the ODP value is zero, the ozone sphere cannot be destroyed if the refrigerant is used for a long time; the GWP value of raw materials is low, and the working pressure of the refrigerant is equivalent to that of R22, so that an existing refrigeration system need not to be modified, the production cost can be reduced, while the refrigeration effect is not reduced; the refrigerant has the effects of inhibiting combustion and explosion, so that the combustibility of the refrigerant can be reduced, and the safety can be improved; the lubricant can seep into each part of a compressor together with the refrigerant so as to create an excellent condition for engine lubrication; tetrahydrothiophene is easily dissolved in difluoromethane and has a strong unpleasant smell, so that when the refrigerant leaks, a user can feel leakage of the refrigerant at the first time and carries out corresponding measures, so that property and safety of people can be protected.

Disclosed herein are a desulfurizing agent for removing organic sulfur compounds, a preparation method thereof, and a method for removing organic sulfur compounds using the same. The desulfurizing agent consists of a copper-zinc-aluminum complex free of alkaline metal, with a large surface area. When being contacted with organic sulfur compounds, such as t-butylmercaptan, tetrahydrothiophene, dimethylsulfide, etc., the desulfurizing agent exhibits excellent desulfurization ability and is not degraded especially at high temperatures as high as 150-350 DEG C.

The invention provides a novel environment-friendly refrigerant, which comprises 95 to 99.7 mass percent of propane 290 and 0.3 to 5 mass percent of tetrahydrothiophene (THT). The refrigeration efficiency of the novel environment-friendly refrigerant is almost the same as that of R22, but the novel environment-friendly refrigerant does not cause damage to ozone layer and has a very low greenhouse effect index. When an air conditioning system using the refrigerant leaks, a user can sense the leakage immediately so as to take measures in time; and thus, the property safety of people is protected.