- Continuous production method for vulcanization accelerator DCBS
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The invention provides a continuous production method for vulcanization accelerator DCBS. The continuous production method includes the steps that an MBT alkali solution, a dicyclohexylamine acid solution, solvent and oxidizing agent are subjected to an oxidizing reaction in a continuous flow reactor, then reacted materials are after-treated, and the vulcanization accelerator DCBS is obtained. According to the method, the MBT conversion percent is high, and the purity of the product is high; the continuous production method has the advantages of being high in reaction speed, high in product yield, low in wastewater COD (reacted wastewater is subjected to atmospheric distillation, residual solvent is recycled, and then the COD in residual water can be reduced to be 8,000 ppm or below), capable of facilitating treatment and the like, and is a new technology having the higher industry value.
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Paragraph 0069-0075; 0080; 0087; 0094; 0101
(2018/10/11)
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- Fluoroalkane thioheterocyclic derivatives and their antitumor activity
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Two series of novel trifluorobutenyl derivatives of heterocyclic with convenient and efficient synthesis methods and their antitumor activity on three cell lines have been reported for the first time. The derivatives were synthesized by the nucleophilic substitution between 4-bromo-1,1,2-trifluorobutene-1-ene and commercially available nitrogen-containing heterocycles with sulfydryl or monosubstituted malononitrile. The twenty-four new compounds were characterized by 1HNMR, 13CNMR and HR-MS. Totally, thirty-seven compounds were evaluated for the antitumor activity on three cancer cell lines (SH-SY5Y, MCF-7 andHepG2) using conventional MTT assay. The pharmacological results indicated that the compounds 3c, 3h, 4c, 8, 9, 10 and 11 showed potent to moderate antitumor activity against three cancer cell lines, with IC50 values ranging between 0.4 μ M and 41.5μ M. Eventhough they had less active than the reference compound taxol against MCF-7 and HepG2 lines, but they were better than the reference compound noscapine against SH-SY5Y cells, especiallythe compound 3h with a IC50 value of 0.4 μM.
- Li, Guangxiao,Sun, Qian,Wang, Dongling,Xu, Ying,Zhuang, Jingjing,Zhang, Qian,Sun, Dequn
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p. 423 - 430
(2015/03/14)
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- Process for the preparation of benzothiazole-2-sulphenamides
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In a process for the production of benzothiazole-2-sulphenamides, a 2-mercaptobenzothiazole in the form of a particulate solid or a dispersion of a particulate solid in a liquid carrier is added gradually and concurrently with an aqueous solution of sodium hypochlorite to a solution of an amine in a mixture of water and a water-miscible organic solvent, the amount of amine being not more than 1.25 moles per mole of 2-mercaptobenzothiazole. A feature of the process is that it represents a significant improvement over prior art methods for the production of sulphenamides derived from secondary amines such as dicyclohexylamine and diisopropylamine.
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- ON THE REACTION OF BENZOTHIAZOL-2-YL SULPHENAMIDES WITH PHOSPHITES
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A study of the synthesis of phosphoramidates from phosphites and benzothiazol-2-yl-sulphenamides, indicates that a quinquecovalent phosphorane is an intermediate.Since the initial step in this reaction does not involve attack of phosphorus on nitrogen, it is unlikely that these sulphenamides will act as electrophilic aminating agents towards non-phosphorus nucleophiles.An efficient new method for preparing benzothiazol-2-yl-sulphenamides is reported.
- Brownbridge, P.,Jowett, I. C.
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p. 311 - 318
(2007/10/02)
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- Process for the preparation of thiazolesulphenamides
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Thiazolesulphenamides, useful as rubber vulcanization accelerators, are made by reaction of a 2-mercapto-thiazole or a 2,2'-dithiazolyl disulphide with ammonia or a primary or secondary amine in the presence of oxygen and a copper catalyst of specified kind.
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