Silicones in Cosmetics
E. Desmond Goddard, James V. Gruber in Principles of Polymer Science and Technology in Cosmetics and Personal Care, 1999
Reactions carried out with alkynes will result in vinyl silanes, which may be further reacted through the unsaturated bond. This synthesis may also be performed using chlorosilanes as opposed to silicon hydrides, but the silicon-chloride bond is stronger than the silicon-hydrogen bond, and thus the reaction with chlorosilanes requires a higher activation energy. These reactions may be catalyzed using ultraviolet light and peroxides in place of platinum (32-34). Under certain conditions alkylfunctional silicones may also be synthesized by condensation reactions or through Grignard syntheses (35). Phenylmodified silanes are generally prepared by a nucleophilic substitution reaction at elevated temperatures ranging from 550 to with the assistance of Grignard reagents .
11C, 13N, and 15O Tracers
Garimella V. S. Rayudu, Lelio G. Colombetti in Radiotracers for Medical Applications, 2019
11CO2 has been used as a precursor in reaction with Grignard reagents to form a series of aliphatic carboxylic acids or with an aryl-lithium compound to form aromatic carboxylic acids.26 Reduction of the carboxylated Grignard reagent with LiAlH4 yields the corresponding alcohol. Straatman et al.27 labeled acetoacetic acid by reacting 11CO2 with the enolate anion of acetone. Carbonation of 3-pyridyl lithium was used to prepare “C-nicotinic acid.28 Carbonating phenylmagnesium bromide with 11CO2 yields 11C-benzoic acid. This can then be enzymatically reacted with glycine to prepare 11C-hippuric acid.29 Rat liver mitochondria, containing benzoyl CoA synthetase and glycine acyltransferase, catalyzed the reactions. 11CO2 has also been used as the labeled precursor in biosynthetic labeling using plant leaves or plant cells. A mixture of 11C-glucose and fructose labeled with C-ll has been prepared by photosynthesis using light-starved Swiss chard30,31 or broad bean32 leaves. Improved yield of labeled glucose and separation of the products by high pressure liquid chromatography has been reported.33, 11C-Mannitol, 11C-galactose, and 11C-glycerol have been synthesized using marine algae.34 An analog of glucose, 2-deoxy-d-glucose, has been labeled by the cyan-ation of 2,3:4,5-di-0-isopropilidene-d-arabinitol followed by the reduction of the ni-trile with Raney Alloy.35
SGLT2 inhibitors for the treatment of diabetes: a patent review (2013-2018)
Published in Expert Opinion on Therapeutic Patents, 2019
Jyotsana Pandey, Akhilesh K Tamrakar
Xu et al. [109] disclosed the methods for the synthesis of SGLT inhibitory compounds and synthetic intermediates for synthesizing such compounds. The process disclosed the use of Grignard reagent to prepare compounds such as: (2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-cyclopropylbenzyl)phenyl)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol and (2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol. The invention by Kwee et al. [110] related to novel dihydrobenzofuran derivatives of chemical formula shown in Figure 5(a), wherein ring B was substituted with different chemical rings, and their pharmaceutically acceptable salts, isomers, hydrates and solvates which have proposed to have inhibitory activity against SGLT. The pharmaceutical efficacy of the compound was confirmed by oral glucose tolerance in mice model and proposed to be used as a therapeutic agent for type I and type II diabetes mellitus and associated complications/diseases caused by hyperglycemia.
Indole derivative XCR-5a alleviates LPS-induced inflammation in vitro and in vivo
Published in Immunopharmacology and Immunotoxicology, 2022
Jiajing Zhao, Prasanta Roy, Haimei Tang, Xingyu Ma, Qianqian Di, Jiazheng Quan, Yonghong Guan, Xiaoli Li, Weilie Xiao, Weilin Chen
N-methoxy-N-methyl-1-(prop-2-yn-1-yl)-1H-indole-2-carboxamide 3 (1.02 g, 4.2 mmol, 1.0 eq) was dissolved in dry THF (10 ml) at room temperature under positive argon pressure and stirred at −78 °C for 10 min. After that, 1 M THF solution of freshly prepared Grignard reagent XCR-4a (12.6 ml, 12.6 mmol, 3 eq) was slowly added to above reaction mixture over 15 min at same temperature, then stirred at 0 °C for another 30 min. After quenching the mixture with aq. NH4Cl (20 ml) at 0 °C, the aqueous layer was extracted with EtOAc (100 ml × 3). The organic extracts were combined, dried over Na2SO4, filtered, and concentrated in vacuum. The resulting solid residue was purified using flash column chromatography on a silica gel before being eluted with a mixture of PE: EtOAc (10:1→5:1) to yield the product, ketone XCR-5a, as an off white solid (0.980 g, 77%); 1H NMR (400 MHz, CDCl3) δ 7.62 (d, J = 8.0 Hz, 1H), 7.54 (d, J = 8.5 Hz, 2H), 7.42 (t, J = 7.7 Hz, 1H), 7.17 (t, J = 7.5 Hz, 1H), 6.85 (s, 1H), 6.81 (d, J = 2.3 Hz, 1H), 6.75 (dd, J = 8.5, 2.5 Hz, 1H), 5.50 (d, J = 2.4 Hz, 2H), 3.85 (s, 3H), 2.45 (s, 3H), 2.26 (t, J = 2.4 Hz, 1H); 13C NMR (101 MHz, CDCl3) δ 190.0, 161.5, 140.4, 139.8, 135.5, 132.1, 126.5, 126.4, 123.3, 121.5, 116.9, 116.3, 110.8, 110.1, 79.1, 72.3, 55.5, 34.2, 20.7.
Design and biological evaluation of substituted 5,7-dihydro-6H-indolo[2,3-c]quinolin-6-one as novel selective Haspin inhibitors
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2022
Sreenivas Avula, Xudan Peng, Xingfen Lang, Micky Tortorella, Béatrice Josselin, Stéphane Bach, Stephane Bourg, Pascal Bonnet, Frédéric Buron, Sandrine Ruchaud, Sylvain Routier, Cleopatra Neagoie
Next, we focussed on preparing the second partner for the cross coupling reaction, that is, the unavailable boronylated nitrobenzene derivatives (Scheme 2). When the starting 2-halogeno nitrobenzenes do not contain any acidic proton, the use of Grignard reagent is recommended in the literature25. The reaction was first carried out with phenyl magnesium chloride (1.2 equiv.) in presence of methylorthoborate as electrophile whereas a final acidic hydrolysis led to the desired 2-nitroaryl boronic acids 15–20 in fair good yields. When 2-halogeno nitrobenzenes bear an acidic proton, the Miyaura borylation reaction can be used with conditions involving PdCl2(dppf) as catalyst and potassium acetate as a base in dioxane. This method furnished pinacol boronic esters 21–24 with modest yields after 14 h of reaction at 80 °C. Due to their sensitivity during the purification step, the boron derivatives were used in the cross coupling reaction as crude materials.
Related Knowledge Centers
- Catalysis
- Chemical Compound
- Diethyl Ether
- Functional Group
- Methylmagnesium Chloride
- Phenylmagnesium Bromide
- Tetrahydrofuran
- Coordination Complex
- Coordinate Covalent Bond
- Grignard Reaction