91401-26-2

Upstream product

• 121-00-6 3-tert-Butyl-4-hydroxyanisole 
• 3380-34-5 triclosan 
• 108-24-7 acetic anhydride 

Relevant academic research and scientific papers

Hydroquinone compounds, preparation methods therefor, and use in anti-tumor or immunomodulation therapy

Disclosed are hydroquinone compounds, preparation methods therefor, and uses thereof in anti-tumor or immunomodulation. The structural formula of the hydroquinone compounds are shown by formula I, wherein X is C═O or CH2; Y is NH, O or absent; R is a substituted or unsubstituted alkyl group having at least one carbon atom, a substituted or unsubstituted cycloalkyl group having at least three carbon atoms, a substituted or unsubstituted alkenyl group or alkynyl group having at least two carbon atoms; and a substituted or unsubstituted aryl group or heteroaryl group containing at least four carbon atoms. The compounds provided slowly release 2-tert-butyl-4-methoxyphenol in vivo and maintain stable plasma concentration of 2-tert-butyl-4-methoxyphenol (T?=12?24 h). The compounds provided by the present invention protect the phenolic hydroxyl group of 2-tert-butyl-4-methoxyphenol, avoid environmental oxidation and increase the environmental stability of drugs containing the compounds.

Simultaneous in-cell derivatization pressurized liquid extraction for the determination of multiclass preservatives in leave-on cosmetics

An effective one-step sample preparation methodology for the determination of multiclass preservatives in cosmetics has been developed, applying, for the first time to this kind of matrix, pressurized liquid extraction (PLE) and a very simple, cheap, and fast derivatization procedure: acetylation with acetic anhydride and pyridine. A multifactorial experimental design has been used to evaluate and optimize the main experimental parameters potentially affecting the extraction process. In the final conditions the sample was mixed with Florisil as the dispersing sorbent and extracted with ethyl acetate for 15 min at 120 °C. One of the main goals of this work was to demonstrate the possibility of carrying out direct cosmetic preservative acetylation by simply adding the derivatization reagents into the PLE cell. The extract was then analyzed by GC/MS without any further cleanup or concentration step. The accuracy, precision, linearity, and detection limits (LODs) were evaluated to assess the performance of the proposed method. Quantitative recoveries were obtained, and relative standard deviation values were lower than 10% in all cases. The obtained LODs ranged from 0.000004% to 0.0001% (w/w), values far below the established restrictions in the European Cosmetics Regulation, making this multicomponent analytical method suitable for routine control. Finally, several cosmetic products such as moisturizing and antiwrinkle creams and lotions, hand creams, sunscreen and after-sun creams, baby lotions, and hair care products were analyzed. All the samples contained several of the target cosmetic ingredients, in some cases at quite high concentrations, although the actual European Cosmetics Regulation was fulfilled in all cases.