26819-07-8Relevant academic research and scientific papers
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.
Base-induced cyclization of derivatives of bispropargylated acetic acid to m -toluic acid
Ali, Tammar Hussein,Heidelberg, Thorsten,Hussen, Rusnah Syahila Duali
, p. 1361 - 1364 (2015/06/16)
A base-induced cyclization reaction of 1,1-bispropargyls has been examined. Alkali treatment of 2,2-bispropynyl acetic acid derivatives in aqueous ethanol mostly provided 3-methylbenzoic acid. Investigations on substituent effects indicate the requirement of an electron-withdrawing group causing CH acidity and the center of the dipropargylic structure. Besides, an intramolecular hydrogen transfer causing the rearrangement of one terminal alkyne into a corresponding allene appears to be essential. Despite an unsatisfying conversion yield of below 40%, the reaction is interesting due to the mild cyclization conditions.
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.
Photolytic degradation of N,N-diethyl-m-toluamide in ice and water: Implications in its environmental fate
Calza,Medana,Sarro,Baiocchi,Minero
, p. 99 - 104 (2013/10/01)
The photochemical transformation of N,N-diethyl-m-toluamide (DEET), one of the most widespread and efficient mosquito repellents, has been investigated. Initially, photoinduced DEET degradation was investigated in liquid samples, at 20 C and 0 C, and in ice (-15 C), aimed to simulate all possible photoinduced processes occurring in water and in cold environments. Under UV-illumination, DEET degradation was more efficient in ice than in water. The evaluation of transformation products (TPs) formed during the photolysis in solution and in ice evidences mostly the same degradation products, but with different concentration ratio and some peculiar differences. An hypothesis about what kind of processes may play a role is reported. In solution, the oxidative process mostly involved were (poly)hydroxylation or oxidation of the hydroxyl groups, while in ice N-dealkylation and monohydroxylation prevail. Finally, DEET and its TPs were searched out in snow and river water in wintertime.
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.
11a-Methano-TXA compounds
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, (2008/06/13)
The present invention provides novel 11a-methano-TXA compounds and intermediates and processs for their preparation. Further provided are methods for using these novel TXA analogs as inhibitors of thromboxane synthetase, rendering these analogs useful for a variety of pharmacological purposes. These pharmacological uses include anti-inflammatory, anti-thromobitc, and anti-asthma indications.
