20816-46-0

Upstream product

• 6305-04-0 p-hydroxyphenacyl chloride 
• 64-19-7 acetic acid 
• 99-93-4 4-Hydroxyacetophenone 
• 2491-38-5 2-bromo-1-(4'-hydroxyphenyl)-1-ethanone 
• 2345-34-8 4-acetyloxy-benzoic acid 
• 27914-73-4 4-acetoxybenzoyl chloride 
• 52727-19-2 4-(2-diazoacetyl)-3-methoxyphenyl acetate 
• 100-66-3 methoxybenzene 
• 2196-99-8 2-chloro-1-(4-methoxyphenyl)ethanone 
• 127-09-3 sodium acetate 
• 127-08-2 potassium acetate 

Downstream Products

• 14199-15-6 Methyl 4-hydroxyphenylacetate 
• 134-04-3 pelargonidin chloride 
• 42528-99-4 2,4’-diacetoxyacetophenone 
• 5706-85-4 2-hydroxy-1-(4-hydroxyphenyl)ethan-1-one 
• 156-38-7 4-hydroxyphenylacetate 

Relevant academic research and scientific papers

Substituted phenacyl molecules and photoresponsive polymers

Substituted phenacyl molecules are provided and employed to create molecules and polymers/copolymers that exhibit photoresponsiveness. In some instances, the substituted phenacyl molecule is incorporated into the polymer/copolymer backbone, and photoirradiation of the polymer/copolymer causes the substituted phenacyl group to break down and the polymer/copolymer to undergo degradation. In other instances, the substituted phenacyl molecules extend as a side chain from the polymer/copolymer backbone. In yet other instances the substituted phenacyl molecules extend as a side chain from the polymer/copolymer backbone, and a drug or polymer additive is linked to the photoresponsive substituted phenacyl group such that photoirradiation releases the drug or additive. In yet other embodiments the substituted phenacyl molecules extend as a side chain from the polymer/copolymer backbone, and serve to link the polymer/copolymer to another polymer/copolymer backbone, and photoirradiation breaks the links.

Silver acetate mediated acetoxylations of alkyl halides

Silver acetate promotes the acetoxylation of alkyl halides under neutral reaction conditions. The reaction is applicable to primary and activated secondary alkyl halides, and 2,2-dibromoacetophenones for preparing the corresponding acetates in good yields. The presence of ester, amide, nitrile, hydroxy, and OTBDMS functions on the substrate is tolerated.

2-Diazo-1-(4-hydroxyphenyl)ethanone: A versatile photochemical and synthetic reagent

α-Diazo arylketones are well-known substrates for Wolff rearrangement to phenylacetic acids through a ketene intermediate by either thermal or photochemical activation. Likewise, α-substituted p-hydroxyphenacyl (pHP) esters are substrates for photo-Favorskii rearrangements to phenylacetic acids by a different pathway that purportedly involves a cyclopropanone intermediate. In this paper, we show that the photolysis of a series of α-diazo-p- hydroxyacetophenones and p-hydroxyphenacyl (pHP) α-esters both generate the identical rearranged phenylacetates as major products. Since α-diazo-p-hydroxyacetophenone (1a, pHP N2) contains all the necessary functionalities for either Wolff or Favorskii rearrangement, we were prompted to probe this intriguing mechanistic dichotomy under conditions favorable to the photo-Favorskii rearrangement, i.e., photolysis in hydroxylic media. An investigation of the mechanism for conversion of 1a to p-hydroxyphenyl acetic acid (4a) using time-resolved infrared (TRIR) spectroscopy clearly demonstrates the formation of a ketene intermediate that is subsequently trapped by solvent or nucleophiles. The photoreaction of 1a is quenched by oxygen and sensitized by triplet sensitizers and the quantum yields for 1a-c range from 0.19 to a robust 0.25. The lifetime of the triplet, determined by Stern-Volmer quenching, is 31 ns with a rate for appearance of 4a of k = 7.1 × 10 6 s-1 in aq. acetonitrile (1:1 v:v). These studies establish that the primary rearrangement pathway for 1a involves ketene formation in accordance with the photo-Wolff rearrangement. Furthermore we have also demonstrated the synthetic utility of 1a as an esterification and etherification reagent with a variety of substituted α-diazo-p- hydroxyacetophenones, using them as synthons for efficiently coupling it to acids and phenols to produce pHP protect substrates. The Royal Society of Chemistry and Owner Societies.

Synthesis and biological evaluation of quinoline salicylic acids as P-selectin antagonists

Leukocyte recruitment of sites of inflammation and tissue injury involves leukocyte rolling along the endothelial wall, followed by firm adherence of the leukocyte, and finally transmigration of the leukocyte across cell junctions into the underlying tissue. The initial rolling step is mediated by the interaction of leukocyte glycoproteins containing active moieties such as sialyl Lewisx (sLex) with P-selectin expressed on endothelial cells. Consequently, inhibition of this interaction by means of a small molecule P-selectin antagonist is an attractive strategy for the treatment of inflammatory diseases such as arthritis. High-throughput screening of the Wyeth chemical library identified the quinoline salicylic acid class of compounds (1) as antagonists of P-selectin, with potency in in vitro and cell-based assays far superior to that of sLex. Through iterative medicinal chemistry, we identified analogues with improved P-selectin activity, decreased inhibition of dihydrooratate dehydrogenase, and acceptable CYP profiles. Lead compound 36 was efficacious in the rat AIA model of rheumatoid arthritis.

Synthesis of [4-14C]-pelargonidin chloride and [4- 14C]-delphinidin chloride

The synthesis of [4-14C]-pelargonidin chloride and [4- 14C]-delphinidin chloride via [formyl-14C]-2-(benzoyloxy)- 4,6-dihydroxybenzaldehyde, ω,4-diacetoxyacetophenone and ω,3,4,5-tetraacetoxyacetophenone is described. The first step comprised labelling of the carbonyl group of 2-(benzoyloxy)-4,6-dihydroxybenzaldehyde, verifying that the coupling with ω,4-diacetoxyacetophenone or ω,3,4,5-tetraacetoxyacetophenone under hydrogen chloride atmosphere resulted in the formation of [4-14C] labelled anthocyanidins. Copyright

Mechanism of photosolvolytic rearrangement of p-hydroxyphenacyl esters: Evidence for excited-state intramolecular proton transfer as the primary photochemical step

The photosolvolytic rearrangement of a variety of p-hydroxyphenacyl esters and related compounds 7-16 has been studied in solutions with up to 50% aqueous content, using product studies, triplet quenchers, and nanosecond laser flash photolysis. The p-hydroxyphenacyl moiety has recently been proposed as a new and efficient photoactivated protecting group in aqueous solution. Practical applications have been demonstrated, but much less is known about the mechanism of photoreaction. Our data support a novel mechanism in which the primary photochemical step from the singlet excited state is formal intramolecular proton transfer from the phenolic proton to the carbonyl oxygen of the distal ketone, mediated by solvent water, to generate the corresponding p-quinone methide phototautomer. This reactive intermediate (most likely in its excited state) subsequently expels the carboxylic acid with concerted rearrangement to a spiroketone intermediate, which subsequently leads to the final observed product, p- hydroxyphenylacetic acid. An alternative mechanism is deprotonation of the phenolic proton, loss of the carboxylate, and rearrangement to the spiroketone, all in one concerted primary photochemical step from S1.