Vanillin 4-hydroxy-3-methoxybenzaldehyde

These trivial names may be retained citral (3,7-dimethyl-2,6-octadienal), vanillin (4-hydroxy-3-methoxybenzaldehyde), and piperonal (3,4-methylenedioxybenzaldehyde). 

Dipping solution Dissolve 1 g vanillin (4-hydroxy-3-methoxybenzaldehyde) in 25 ml ethanol and add 25 ml water and 35 ml ortAo-phosphoric acid. 

Another phenolic compound isolated from Palmer amaranth was vanillin (4-hydroxy-3-methoxybenzaldehyde). This compound has been previously reported in extracts of soils, plant roots and leaf... 

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is widely used in foods, beverages, perfumes and the pharmaceuticals industries. Biotransformation of isoeugenol from essential oil to vanillin represents an economic route for the supply of vanillin, which has a limited supply due to the availability of vanilli pod plants. The conversion yield of isoeugenol to vanillin by the whole-cell biotransformation process of Bacillus fusiformis was low due to the product inhibition effect. Adding resin HD-8 to the whole-cell biotransformation eliminated the product inhibition effect, yielding 8 gL 1 of vanillin in the final reaction mixture [27]. The resin HD-8 also facilitated the separation of vanillin from the used substrate. The recovered isoeugenol can be used for the subsequent biotransformation reaction. 

Vanillin (4-hydroxy-3-methoxybenzaldehyde) in ethanolic solution - as supplied as a flavouring agent - was dimerized by sunlight or more rapidly under a mercury lamp to dehydrodivanillin (3). This is a typical ortho-phenol coupling reaction [20],... 

The molecular structures of vanillin (4-hydroxy-3-methoxybenzaldehyde), isovanillin (3-hydroxy-4-methoxybenzaldehyde) and ethylvanillin(3-ethoxy-4-hydroxybenzaldehyde) were determined by Egawa et al. (2006) by means of gas electron diffraction. Among them, vanillin and ethylvanillin have a vanilla odour but isovanillin smells different. Vanillin and isovanillin have two stable con-formers and ethylvanillin has four. 

Fig. 4-1. Examples of classical methods indicating a phenylpropanoid structure of lignin. (A) Permanganate oxidation (methylated spruce lignin) affords veratric acid (3,4-dimethoxybenzoic acid) (1) in a yield of 8% and minor amounts of isohemipinic (4,5-dimethoxyisophtalic acid) (2) and dehydrodiveratric (3) acids. The formation of isohemipinic acid supports the occurrence of condensed structures (e.g., /3-5 or y-5). (B) Nitrobenzene oxidation of softwoods in alkali results in the formation of vanillin (4-hydroxy-3-methoxybenzaldehyde) (4) (about 25% of lignin). Oxidation of hardwoods and grasses results, respectively, in syringaldehyde (3,5-dimethoxy-4-hydroxybenzaldehyde) (5) and p-hydroxybenzaldehyde (6). (C) Hydrogenolysis yields pro-pylcyclohexane derivatives (7). (D) Ethanolysis yields so-called Hibbert ketones (8,9,10, and 11).

Vanillin (4-hydroxy-3-methoxybenzaldehyde) [121-33-5] M 152.2, m 83 , b 170 /15mm, pK 7.40. Crystd from water or aqueous EtOH, or by distn in vacuo. 

Vanillin. Vanillin (4-hydroxy-3-methoxybenzaldehyde) is a well-known, naturally occurring compound present in small quantities in many plants, particularly the pod of the vanilla orchid. It is also found in potato parings, in sugar beets, in balsams, and in other natural oils and resins. Vanillin can be synthesized, and it is expected that field tests with this material will be started in the foreseeable future. 

Artificial vanilla flavoring is a solution of pure synthesized vanillin, 4-hydroxy-3-methoxybenzaldehyde. Mixtures of vanillin with other toxicants enhance mutagenic effects 31 and produce synergistic inhibition of lignocellulose degradation when mixed with catechol. 32 Vanillin potentiates the hepatotoxicity of carbon tetrachloride. 331 Mixtures of vanillin and cigarette smoke condensates induce sister-chromatid exchanges. 34 ... 

The reactivity of nucleophilic sites of phloroglucinol nucleis with aldehydes has been known for a long time. Using formaldehyde a condensation product is formed which precipitates and can be determined gravimetrically [111]. Colorimetric procedures using substituted benzaldehydes are more popular. The most often used substituted benzaldehyde is vanillin (4-hydroxy-3-methoxybenzaldehyde). Protocols based on dimethylaminocinnamaldehyde have gained interest in the last few years, whereas 2,4-dimethoxybenzaldehyde [132]- although more sensitive than vanillin [133] - is not anymore used. 

Biphasic sonoelectroanalysis was employed in the detection of vanillin (4-hydroxy-3-methoxybenzaldehyde) using the novel electrochemical and sonoelec-trochemical solvent ethyl acetoacetate [88]. The electrochemical oxidation of vanillin in this medium was shown to give oxidative Knear sweep voltammetric signals sensitive to microadditions. In addition. 

Vanilla flavouring compounds belong to the most widely used additives in food, drinks and cosmetics. Natural vanilla extract is used in perfumes, soaps, medicines, soft drinks, and sweets. The basic flavouring compound in natural vanilla is vanillin (4-hydroxy-3-methoxybenzaldehyde). However, natural vanilla contains only 1-3% vanillin." " There are over 130 more compounds which contribute to the unique flavour and aroma of natural vanilla, among them are vanillic acid, 4-hydroxybenzaldehyde and 4-hydroxybenzoic acid.""... 

Vanillin (4-hydroxy-3-methoxybenzaldehyde), the principal component of vanilla, occurs in vanilla beans and other natural sources as a /3-D-glucopyranoside. Draw a structural formula for this glycoside, showing the D-glucose unit as a chair conformation. 

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is the most important flavor ingredient available on the market. Natural vanillin is extracted from the beans, or pods, of the orchid Vanilla planifolia, V. tahitiensis, and V fragrans, mainly cultivated in Madagascar, Mexico, Tahiti, and Indonesia. Natural vanilla flavor supplies cover 1% of the demand the remainder is synthesized cheaply by chemical routes. Vanillin is employed not only in the F F industry, but it is also a key intermediate in the production of chemicals and pharmaceuticals (e.g., drugs, herbicides, antimicrobial agents, antifoaming agents) [31]. 

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