Salicylic Aldehydes (salicylic + aldehyde)

Distribution by Scientific Domains


Selected Abstracts


Potassium Carbonate-Catalyzed Reactions of Salicylic Aldehydes with Allenic Ketones and Esters: an Effective Way to Synthesize Functionalized 2H -Chromenes

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2006
Min Shi
Abstract Potassium carbonate-catalyzed reactions of salicylic aldehydes with 3-methylpenta-3,4-dien-2-one, 3-benzylpenta-3,4-dien-2-one or ethyl 2-methylbuta-2,3-dienoate gave the corresponding functionalized 2H -1-chromenes in good to excellent yields and good stereoselectivities in some cases in DMSO at 120,C within 1,h, respectively. [source]


ChemInform Abstract: Dual Organocatalytic Ion-Pair Assemblies: A Highly Efficient Approach for the Enantioselective Oxa-Michael,Mannich Reaction of Salicylic Aldehydes with Cyclohexenones.

CHEMINFORM, Issue 21 2010
Ai-Bao Xia
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


A Facile Synthetic Route to 2H-Chromenes: Reconsideration of the Mechanism of the DBU-Catalyzed Reaction Between Salicylic Aldehydes and Ethyl 2-Methylbuta-2,3-dienoate.

CHEMINFORM, Issue 35 2007
Lun-Zhi Dai
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]


A Facile Synthetic Route to 2,H -Chromenes: Reconsideration of the Mechanism of the DBU-Catalyzed Reaction between Salicylic Aldehydes and Ethyl 2-Methylbuta-2,3-dienoate,

CHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2007
Lun-Zhi Dai
Abstract Reactions of salicylaldehydes with ethyl buta-2,3-dienoate or penta-3,4-dien-2-one catalyzed by a catalytic amount of potassium carbonate produce the corresponding 2,H -chromene products in moderate to good yields under mild conditions. A plausible reaction mechanism is discussed in the light of the results of an 18O-labeling experiment. In addition, in view of these findings, the catalytic function of DBU in reactions of this kind is reconsidered. [source]


The protective effect of hydroxyl-substituted Schiff bases on the radical-induced oxidation of DNA

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 9 2009
Feng Zhao
Abstract The protective effects of 18 hydroxyl-substituted Schiff bases (SchOHs) on the oxidative damage of naked DNA induced by 2,2,-azobis(2-amidinopropane hydrochloride) (AAPH) were reported, in which SchOHs were prepared by condensing hydroxyl-substituted aromatic aldehydes and anilines. The extent of the oxidative damage of DNA was followed by measuring the formation of thiobarbituric acid reactive substance (TBARS). Some SchOHs bearing only one hydroxyl group (prepared by salicylic aldehyde) protected DNA by decreasing the formation rate of TBARS. Other SchOHs inhibited the oxidation of DNA for a period, resulting in an inhibition period (tinh) that was proportional to the concentration of SchOH, viz., tinh,=,(n/Ri)[SchOH]. Thus, the stoichiometric factor (n) can be calculated if the initiation rate (Ri) was known. The n value of an SchOH was closed to the summation of the n from every structural feature in this SchOH, indicating that the antioxidant activity of SchOH was contributed from every structural feature in the molecule. Furthermore, the large conjugative system and para -hydroxyl at benzilidene were good for the antioxidant activity of SchOHs. Copyright 2009 John Wiley & Sons, Ltd. [source]


A new catalytic activity from tobacco converting 2-coumaric acid to salicylic aldehyde

PHYSIOLOGIA PLANTARUM, Issue 3 2007
Jacek Malinowski
Salicylic acid (SA) mediates plant response to pathogen invasion, resulting in hypersensitive response and in the formation of systemic acquired resistance. It is well known that Nicotiana tabacum and other plants respond to Tobacco Mosaic Virus (TMV) infection by increasing the content of SA but the details of SA biosynthesis are still not fully understood. Generally, SA may originate directly from isochorismate (Arabidopsis thaliana), or its C6,C1 skeleton could be synthesized via the phenylpropanoid pathway by ,-oxidation of trans -cinnamic acid (N. tabacum), 2-coumaric acid (OCA) (Gaulteria procumbens, Lycopersicum esculentum) or by retro-aldol reaction of trans -cinnamoyl-CoA (Hypericum androsaemum). We report here a novel putative enzyme activity from tobacco, salicylic aldehyde synthase (SAS), catalysing non-oxidative formation of salicylic aldehyde (SALD) directly from OCA. This chain-shortening activity is similar to that of 4-hydroxybenzaldehyde synthase from Vanilla planifolia, Lithospermum erythrorhizon, Daucus carota, Solanum tuberosum and Polyporus hispidus but the enzyme differs in the kinetics of the reaction, substrate specificity and requirements for reducing cofactors. SAS activity is constitutively expressed in healthy tobacco leaves and doubles as a result of infection with TMV. Moreover, the product of SAS activity,SALD, applied exogenously on tobacco leaves, stimulates peroxidase activity and enhances resistance to consecutive infection with TMV. These observations could suggest a contribution of SAS and SALD to the response of tobacco to TMV infection. [source]


Potassium Carbonate-Catalyzed Reactions of Salicylic Aldehydes with Allenic Ketones and Esters: an Effective Way to Synthesize Functionalized 2H -Chromenes

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2006
Min Shi
Abstract Potassium carbonate-catalyzed reactions of salicylic aldehydes with 3-methylpenta-3,4-dien-2-one, 3-benzylpenta-3,4-dien-2-one or ethyl 2-methylbuta-2,3-dienoate gave the corresponding functionalized 2H -1-chromenes in good to excellent yields and good stereoselectivities in some cases in DMSO at 120,C within 1,h, respectively. [source]