3694-52-8Relevant articles and documents
Simple, high yield preparation of 3-nitro-1,2-phenylenediamine
Milata, Viktor,Salon, Jozef
, p. 347 - 348 (1999)
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Preparation method of 4-amino-1, 3-dihydro-benzimidazole-2-one
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Paragraph 0041, (2020/07/15)
The invention provides a preparation method of 4-amino-1, 3-dihydro-benzimidazole-2-one, which comprises the following steps: Q1, preparation of 2, 6-dinitrochlorobenzene, Q2, preparation of 2, 6-dinitroaniline, Q3, preparation of 3-nitro-o-phenylenediamine, Q4, preparation of 4-nitro-1H-benzo[d]imidazole-2(3H)-one and Q5, preparation of 4-amino-1, 3-dihydro-benzimidazole-2-one. According to the preparation method, 3, 5-dinitro-4-chlorobenzoic acid which is low in price is used as a raw material, and the high-yield 4-amino-1, 3-dihydro-benzimidazole-2-one is obtained through reactions such asdecarboxylation and ammoniation. The whole reaction process is easy to control, the product yield is high, good social benefits and economic benefits can be brought, and the economic value potential is large.
Atom-Specific Mutagenesis Reveals Structural and Catalytic Roles for an Active-Site Adenosine and Hydrated Mg2+ in Pistol Ribozymes
Neuner, Sandro,Falschlunger, Christoph,Fuchs, Elisabeth,Himmelstoss, Maximilian,Ren, Aiming,Patel, Dinshaw J.,Micura, Ronald
supporting information, p. 15954 - 15958 (2017/11/21)
The pistol RNA motif represents a new class of self-cleaving ribozymes of yet unknown biological function. Our recent crystal structure of a pre-catalytic state of this RNA shows guanosine G40 and adenosine A32 close to the G53–U54 cleavage site. While the N1 of G40 is within 3.4 ? of the modeled G53 2′-OH group that attacks the scissile phosphate, thus suggesting a direct role in general acid–base catalysis, the function of A32 is less clear. We present evidence from atom-specific mutagenesis that neither the N1 nor N3 base positions of A32 are involved in catalysis. By contrast, the ribose 2′-OH of A32 seems crucial for the proper positioning of G40 through a H-bond network that involves G42 as a bridging unit between A32 and G40. We also found that disruption of the inner-sphere coordination of the active-site Mg2+ cation to N7 of G33 makes the ribozyme drastically slower. A mechanistic proposal is suggested, with A32 playing a structural role and hydrated Mg2+ playing a catalytic role in cleavage.