- Preparation method of cyclic poly (butylene terephthalate) (by machine translation)
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The invention discloses a cyclic trimetric polybutylene terephthalate preparation method. The method comprises the steps: (a) preparing bis(4-(4-allyl terephthaloyl oxy)butyl)polyethylene terephthalate (III) from bis-(4-hydroxyl butyl)-polyethylene terephthalate (I) and 4-(allyloxy carbonyl)benzoic acid (II) under action of a condensing agent and an auxiliary reagent; (b) preparing cyclic trimetric polybutylene terephthalate precursor (IV) by ring closure of the bis(4-(4-allyl terephthaloyl oxy)butyl)polyethylene terephthalate (III) under the action of a Grubbs catalyst and lewis acid; (c) hydrogenating the cyclic trimetric polybutylene terephthalate precursor under the action of Pd/C to obtain cyclic trimetric polybutylene terephthalate (V). The preparation method disclosed by the invention has the advantages that the raw materials are cheap and easy to obtain, a synthesizing route is simple and short, a yield is high, and conditions are easy to control.(The formula is shown in the description.).
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Paragraph 0040-0049
(2020/06/02)
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- Preparation method and separation method of low polymerization cyclic polymer
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The invention provides a preparation method of a low polymerization cyclic polymer, and the method comprises the following steps: (1-1) in an organic solvent A, terephthaloyl chloride and 1,4-butanediol undergo esterification reaction under the action of
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Paragraph 0187-0235
(2019/11/20)
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- A practical synthesis of the cyclic butylene terephthalate trimer
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This paper described a practical synthetic approach for the cyclic butylene terephthalate trimer (7). The key step was a ring-closing metathesis, using Grubbs' second-generation catalyst to form the macrocyclic ring. The advantages of this procedure included short reaction steps, simple operations and good yields.
- Li, Xiaolin,Zhou, Pu,Wu, Wenxuan,Zhan, Li,Liu, Ting,Yang, Fan,Tang, Jie,Yu, Shanbao,Li, Hui,Luo, Yu
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p. 483 - 490
(2018/03/27)
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- Preparation method of cyclic tetrapolybutylene terephthalate
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The invention discloses a preparation method of cyclic tetrapolybutylene terephthalate. The method comprises the steps as follows: a) an initial material, namely, terephthaloyl dichloride, reacts with1,4-butanediol under the action of an alkaline reagent, and terephthalic bis(4-hydroxyl-butyl)ester, namely, a compound I, is obtained; b) the compound I reacts with monobenzyl terephthalate under the action of a condensing agent, and bis(4-(4-benzyloxy terephthaloyl)butyl)terephthalate, namely, a compound II, is obtained; c) the compound II is dissolved in a proper solvent, a catalyst is added to reduce debenzylation under the action of palladium-carbon and hydrogen, and 4,4'-[terephthaloyl bis(oxytetramethylene oxycarbonyl)]dibenzoic acid, namely a compound III, is obtained; d) the compoundIII reacts with the compound I under the action of a condensing agent, and the target product, namely, cyclic tetrapolybutylene terephthalate, is obtained. The method is low in cost, short in synthesis route, convenient to operate, high in product quality and good in industrial application value.
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Paragraph 0058; 0059; 0062; 0065; 0068
(2018/09/12)
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- Cyclic polybutylene terephthalate preparation
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The invention specifically discloses a preparation method of novel cyclicpolybutylece terephthalate (PBT) dimer, wherein paraphthaloyl chloride and 1,4-butanediol are used as the raw materials for oriented synthesis of the cyclicpolybutylece terephthalate dimer through a protection and deprotectionstrategy, and the method is used for contrast analysis and detection of cyclicpolybutylece terephthalate dimer impurities in a PBT plastic. The chemical structural formula of the cyclicpolybutylece terephthalate dimer is described in the specification.
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- Polybutylene terephthalate cyclic trimerization preparation of (by machine translation)
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The invention specifically has described a kind of new cyclic trimeric butylene terephthalate (Cyclic PBT Dimer) method for preparing, in the terephthalic chloride and 1, the 4 the protecting [...] butanediol as raw material with oriented synthesis strategy of deprotection of the polybutylene terephthalate cyclic trimerization, in the plastics can be used for the PBT polybutylene terephthalate cyclic trimerization contrast analysis of the impurity with the detection. Said product of this invention the chemical structural formula is: (by machine translation)
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- Synthesis and biological evaluation of novel AM80 derivatives as antileukemic agents
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A series of novel AM80 derivatives as antileukemic agents were synthesized and their structures were confirmed by IR, 1H-NMR, and HR-MS spectra. All the target compounds were evaluated for in vitro antiproliferative activities against human leukemic HL-60, NB4, and K562 cell lines. Among these derivatives, compound 4g showed much stronger antiproliferative activities against all the three human leukemic cell lines than the positive control AM80, and compound 4b exhibited more active antiproliferative effects against HL-60 and K562 cells than AM80. Furthermore, the preliminary SAR analysis suggested that AM80 conjugating with HDAC inhibitors with small steric hindrance could give more effective antileukemic agents. These results would be helpful to design more potent antileukemic drugs for the treatment of human leukemia.
- Bian, Haiyong,Feng, Jinhong,Xu, Wenfang
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p. 175 - 185
(2013/03/13)
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- Novel antileukemic agents derived from tamibarotene and nitric oxide donors
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A series of novel nitric oxide-releasing tamibarotene derivatives were synthesized by coupling nitric oxide (NO) donors with tamibarotene via various spacers, and were evaluated for their antiproliferative activities against human leukemic HL-60, NB4 and
- Bian, Haiyong,Feng, Jinhong,Li, Minyong,Xu, Wenfang
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p. 7025 - 7029
(2012/01/05)
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