26819-07-8Relevant articles and documents
A novel pleuromutilin derivative and its preparation method and anti-tumor use
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Paragraph 0034; 0035; 0118; 0119, (2017/07/04)
The invention relates to novel pleuromutilin derivatives shown in the structural general formula (I), as well as a preparation method and an application thereof in preparation of a medicine for treating tumour, and particularly colorectal cancer diseases. In-vitro biological activity tests indicate that the derivatives have inhibitory activity on three types of colorectal cancer cells.
The α-effect in hydrazinolysis of 4-chloro-2-nitrophenyl x-substituted-benzoates: Effect of substituent x on reaction mechanism and the α-effect
Kim, Min-Young,Kim, Tae-Eun,Lee, Jieun,Um, Ik-Hwan
, p. 2271 - 2276 (2014/09/29)
Second-order rate constants (kN) have been measured spectrophotometrically for the reaction of 4-chloro-2- nitrophenyl X-substituted-benzoates (6a-6h) with a series of primary amines including hydrazine in 80 mol % H2O/20 mol % DMSO at 25.0°C. The Bronsted-type plot for the reaction of 4-chloro-2-nitrophenyl benzoate (6d) is linear with βnuc = 0.74 when hydrazine is excluded from the correlation. Such a linear Bronsted-type plot is typical for reactions reported previously to proceed through a stepwise mechanism in which expulsion of the leaving group occurs in the rate-determining step (RDS). The Hammett plots for the reactions of 6a-6h with hydrazine and glycylglycine are nonlinear. In contrast, the Yukawa-Tsuno plots exhibit excellent linear correlations with ?X = 1.29-1.45 and r = 0.53-0.56, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by resonance stabilization of the substrates possessing an electron-donating group (EDG). Hydrazine is ca. 47-93 times more reactive than similarly basic glycylglycine toward 6a-6h (e.g., the α-effect). The α-effect increases as the substituent X in the benzoyl moiety becomes a stronger electronwithdrawing group (EWG), indicating that destabilization of the ground state (GS) of hydrazine through the repulsion between the nonbonding electron pairs on the two N atoms is not solely responsible for the substituent-dependent α-effect. Stabilization of transition state (TS) through five-membered cyclic TSs, which would increase the electrophilicity of the reaction center or the nucleofugality of the leaving group, contributes to the α-effect observed in this study.
Method For Producing Tertiary Amides Of Alkylphenyl Carboxylic Acids
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Page/Page column 5-6, (2010/04/25)
The invention relates to a method for producing tertiary amides of alkylphenyl carboxylic acids by reacting at least one secondary amine with at least one alkylphenyl carboxylic acid to form an ammonium salt, said ammonium salt being subsequently converted into the tertiary amide by means of microwave radiation.