硫酸甲基的皮肤敏感化数据 - - 对已公布的数据库进行必要的校正
1School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, UK.
Contact dermatitis
|November 8, 2023
概括
鼠局部淋巴结测定 (LLNA) 数据需要仔细审查. 对硫酸的EC3值进行重新评估,发现了显著的差异,强调需要对数据库进行更正,以确保可靠的化学安全评估.
科学领域:
- 化学安全评估 化学安全评估
- 毒理学 毒理学 毒理学
- 皮肤病学 皮肤病学
背景情况:
- 小鼠局部淋巴结测定 (LLNA) 数据库包含硫酸的EC3值.
- 由于错误识别的化学物质或不适当的EC3值外推,一些数据库条目存在疑问.
研究的目的:
- 调查LLNA数据是否归因于不正确的化学品.
- 解决化学安全评估中不恰当外推EC3值的问题.
主要方法:
- 用单剂量探针抽取方法 (SDPEM) 对特定甲基硫酸盐和苏的剂量反应数据进行了重新评估.
- 分析了不同硫酸盐的反应化学概况.
主要成果:
- 对六甲-1--1,3-苏尔的额外推算EC3值在两种方法之间是一致的.
- 在重新评估时,观察到甲基硫酸盐的EC3值存在显著差异.
结论:
- 目前的化学数据库需要对LLNA数据进行更正.
- 需要进一步分析,以确定由于不适当的推断而导致的不可靠的EC3值.
相关概念视频
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Overview
The Fischer esterification reaction was developed by the German chemist Emil Fischer in 1895. It is a condensation reaction between carboxylic acids and alcohols in an acidic medium to give esters and water.
Carboxylic Acids to Methylesters: Alkylation using Diazomethane
Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
Naming Acid Halides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
Esters to Carboxylic Acids: Saponification
Esters can be hydrolyzed to carboxylic acids under acidic or basic conditions. Base-promoted hydrolysis of esters is a nucleophilic acyl substitution reaction in which esters react with an aqueous base, followed by an acid to give carboxylic acids. This reaction is also known as saponification because it forms the basis for making soaps from fats.
The reaction requires a base in stoichiometric amounts, which participates in the reaction and is not regenerated later. So, the base acts as a...
The reaction requires a base in stoichiometric amounts, which participates in the reaction and is not regenerated later. So, the base acts as a...
Esters to Carboxylic Acids: Acid-Catalyzed Hydrolysis
Hydrolysis of esters under acidic conditions proceeds through a nucleophilic acyl substitution. In the presence of excess water, the reaction proceeds in a reversible manner, forming carboxylic acids and alcohols.
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism
Carboxylic acids react with alcohols to yield esters via an acid-catalyzed condensation reaction called Fischer esterification. This is a nucleophilic acyl substitution reaction that proceeds via a tetrahedral intermediate, where a water molecule is eliminated as the leaving group.


