Photoinduced Specific Acylation of Phenolic Hydroxy Groups with Aldehydes

Candida antarctica lipase B proved to be highly active in the deacylation of substituted hydroquinones and resorcinols acylated at both phenolic hydroxy groups. The deacylation reactions were much faster than the corresponding direct acylations of these dihydroxybenzenes catalyzed by the same lipase. More importantly, they took place generally in a markedly regioselective manner: the acyloxy group remote from the substituent was preferentially cleaved. The main or exclusive products obtained were the regioisomers of those produced through the direct acylation of the dihydroxybenzenes. In the case of alkyl-substituted hydroquinone derivatives, the regioselectivity increased with an increase in the bulk of the substituent. In the case of 4-substituted diacylated resorcinols, the 3-O-monoacyl derivatives were obtained generally as the sole products. Quite interestingly, some secondary alcohols proved to act as better acyl acceptors than the corresponding primary alcohols in these enzymatic deacylations.

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Enzymatic Sulfation of Phenolic Hydroxy Groups of Various Plant Metabolites by an Arylsulfotransferase

European Journal of Organic Chemistry ◽

10.1002/ejoc.201402875 ◽

2014 ◽

Vol 2015 (3) ◽

pp. 534-541 ◽

Cited By ~ 15

Author(s):

Michael A. van der Horst ◽

Aloysius F. Hartog ◽

Rabab El Morabet ◽

Arthur Marais ◽

Menzo Kircz ◽

...

Keyword(s):

Plant Metabolites ◽

Hydroxy Groups ◽

Phenolic Hydroxy

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Study on organosilicon positive resist. I. Syntheses and characterization of silsesquioxane, siloxane, and silmethylene polymers with phenolic hydroxy groups

Journal of Applied Polymer Science ◽

10.1002/app.1992.070440909 ◽

1992 ◽

Vol 44 (9) ◽

pp. 1573-1582 ◽

Cited By ~ 2

Author(s):

Hisashi Sugiyama ◽

Takashi Inoue ◽

Kazuo Nate

Keyword(s):

Hydroxy Groups ◽

Phenolic Hydroxy ◽

Positive Resist

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A New Type of Double Calix[4]arenes by Linkage via the Phenolic Hydroxy Groups

Angewandte Chemie International Edition in English ◽

10.1002/anie.199002801 ◽

1990 ◽

Vol 29 (3) ◽

pp. 280-282 ◽

Cited By ~ 29

Author(s):

M. Anthony McKervey ◽

Michael Owens ◽

Hans-Rolf Sehulten ◽

Walter Vogt ◽

Volker Böhmer

Keyword(s):

New Type ◽

Hydroxy Groups ◽

Phenolic Hydroxy

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Superoxide Anion Scavenging Effect of Coumarins

The American Journal of Chinese Medicine ◽

10.1142/s0192415x96000037 ◽

1996 ◽

Vol 24 (01) ◽

pp. 11-17 ◽

Cited By ~ 58

Author(s):

Wen-Shin Chang ◽

Chun-Ching Lin ◽

Shu-Chuan Chuang ◽

Hsuch-Ching Chiang

Keyword(s):

Cytochrome C ◽

Xanthine Oxidase ◽

Superoxide Anion ◽

Folk Medicine ◽

Ortho Position ◽

Scavenging Activity ◽

Percent Inhibition ◽

Scavenging Effect ◽

Hydroxy Groups ◽

Phenolic Hydroxy

The superoxide scavenging effects of fifteen coumarins were tested on the xanthine-xanthine oxidase-cytochrome C system. The results showed that fraxetin(10) displayed the strongest activity, and its percent inhibition at 100, 10 and 1 μM were 100, 100 and 53.13% respectively. Esculetin(4) showed the second strongest activity resulting in percent inhibition at 100 and 10 μM were 87.16 and 52.38% respectively. Both fraxetin(10) and esculetin(4) have been isolated from the plant, Fraxinus bungeana DC (Oleaceae) which has been used in folk medicine as an analgesic and anti-inflammatory medicine. It seems that two phenolic hydroxy groups in the ortho position in the molecule of coumarins play an important role in scavenging activity.

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