- Synthesis method of benzidine compound
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The invention discloses a synthesis method of a benzidine compound. A compound (I) is subjected to catalytic coupling reaction to obtain a compound (II); the compound (II) is subjected to alkaline oracidic hydrolysis reaction process to obtain a compound (III); the compound (III) is subjected to catalytic hydrogenation reduction reaction in an organic system to obtain a benzidine compound (V); orthe compound (II) is subjected to catalytic hydrogenation reduction reaction in an organic solvent to obtain a compound (V); the compound (V) is subjected to alkaline or acidic hydrolysis reaction toobtain a compound (IV). The method disclosed by the invention overcomes various defects of the existing method; the conventional commercial catalysts are used; the reaction time is greatly shortened;the capacity is improved. Noteworthily, the organic solvent can be recovered and reused; hydroiodic acid or hydrobromide generated through coupling reaction can be smoothly converted into iodides orbromide salts with high economic values through treatment. Therefore, the method disclosed by the invention is an economic easy-to-industrialize green method.
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Paragraph 0047; 0048; 0051; 0052-0053; 0059; 0061
(2018/07/30)
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- Synthesis process of medical and chemical intermediate 3,3'-dinitro-4,4'-diacetylbiphenyldiamine
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The invention discloses a synthesis process of a medical and chemical intermediate 3,3'-dinitro-4,4'-diacetylbiphenyldiamine. The synthesis process comprises the following steps: putting raw materials including concentrated nitric acid, concentrated sulfuric acid, 3,3'-diaminobenzidine, acetic anhydride and the like into an ice water bath and carrying out operation means including magnetic stirring and the like to prepare the 3,3'-dinitro-4,4'-diacetylbiphenyldiamine.
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Paragraph 0030-0035; 0036
(2017/07/19)
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- Design, synthesis, and anti-tumor evaluation of novel symmetrical bis-benzimidazoles
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A novel symmetrical bis-benzimidazole was designed as DNA minor groove binder. Molecular modeling study showed that it could dock into the minor groove of DNA. Several derivatives were synthesized and confirmed by IR, MS, and 1H NMR. All these novel compounds were screened for cytotoxic activity on SKOV-3, HeLa, and BGC-823 cell lines in vitro. Some compounds showed IC50s in the single-digit micromolar range for cytotoxicity in several tumor cell lines.
- Yang, Yan-Hui,Cheng, Mao-Sheng,Wang, Qing-He,Nie, Han,Liao, Na,Wang, Jian,Chen, Hong
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experimental part
p. 1808 - 1812
(2009/06/28)
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- A NOVEL CATALYTIC PROCESS FOR THE PRODUCTION OF 3,3', 4,4'-TETRAMINOBIPHENYL
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This invention relates to a process for the production of 3,3’, 4,4’-tetraminobiphenyl (TAB) of formula (1) from non-carcinogenic raw materials, employing Suzuki type biaryl coupling as the key step. sMore particularly, it relates to a three steps process for the production of TAB comprising biaryl aryl coupling of 2-nitro-4-bromoacetanilide (NBA) of formula (2) catalyzed by sulfilimine based palladacycles as catalysts followed by the basic hydrolysis of acetyl group and the reduction of nitro groups with conventional reducing agents.
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Page/Page column 5; 7-8
(2010/02/14)
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- Symmetric bis-benzimidazoles: New sequence-selective DNA-binding molecules
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A series of bis-benzimidazole compounds with a head-to-head orientation have been designed as sequence-specific DNA binders; crystallographic analysis of oligonucleotide complexes has been combined with DNase I footprinting to confirm that the predicted optimal site for the core bisbenzimidazole motif is the four-base-pair sequence 5'-AATT; this sequence specificity results in inhibition of transcription at A/T sites and may be responsible for the cytotoxic and antitumour effects shown by these head-to-head bis-benzimidazoles.
- Neidle, Stephen,Mann, John,Rayner, Emma L.,Baron, Anne,Opoku-Boahen, Yaw,Simpson, Ian J.,Smith, Nicola J.,Keith R, Fox,Hartley, John A.,Kelland, Lloyd R.
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p. 929 - 930
(2007/10/03)
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- Models for intramolecular exchange in organic π-conjugated open-shell systems: A comparison of three non-kekule biphenyldinitrenes
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The important effect of connectivity upon the nature of intramolecular exchange coupling of unpaired electrons by the biphenyl group was investigated by cryogenic matrix photolysis of diazide precursors expected to yield biphenyl-3,4′-dinitrene (1), biphenyl-3,3′-dinitrene (2), and biphenyl-4,4′-dinitrene (3). System 1 was predicted by parity-based qualitative models to exhibit a high-spin ground state. By Curie law analysis of its electron spin resonance (ESR) spectrum at cryogenic temperatures in frozen 2-methyltetrahydrofuran solution, 1 was found to be a quintet ground-state dinitrene with zero field splitting (zfs) parameters of |D/hc| = 0.153 cm-1, |E/hc| = 0.003 cm-1. System 2 was predicted to be disjoint with nearly-degenerate high-spin and low-spin states. Cryogenic frozen solution ESR spectroscopy showed no ESR-active dinitrene 2 upon extended photolysis of its appropriate diazide precursor, although the related mononitrene with zfs of |D/hc| = 0.996 cm-1 was clearly visible. We presume that system 2 was produced in this experiment, but that it acts either as a singlet ground-state dinitrene or as a pair of isolated mononitrenes. A biradical ESR spectrum was found for photolysis of the diazide precursor to 3, with zfs of |D/hc| = 0.189 cm-1 and |E/hc| -1. The thermal dependence of this biradical spectrum shows it to be an excited state, consistent with quinonoidal dinitrene 3 having a singlet ground state and a triplet excited state ca. 0.6 kcal/mol higher in energy. The results for dinitrenes 1-3 were compared to related work on dicarbene molecules described by others, and it was found that the dinitrenes and dicarbenes exhibit similar electron exchange coupling behavior.
- Minato, Masaki,Lahti, Paul M.,Van Willigen, Hans
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p. 4532 - 4539
(2007/10/02)
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