Veratraldehyde,

CgHjoO,. A compound of largely historical interest for its role in establishing the structure of many natural products. Methylation of vanillin gives veratraldehyde which may be oxidized to veratric acid. Veratric acid was identified as a degradation product of the alkaloid papaverine. 

Veratronitrile, Dissolve 83 g. of veratraldehyde in 200 ml. of warm rectified spirit in a 1 litre bolt-head flask, and add a warm solution of 42 g. of hydroxylamine hydrochloride in 50 ml. of water. Mix thoroughly and run in a solution of 30 g. of sodium hydroxide in 40 ml. of water. Allow the mixture to stand for 2-5 hours, add 250 g. of crushed ice, and saturate the solution with carbon dioxide. The aldoxime separates as an oil allow the mixture to stand for 12-24 hours in an ice chest or refrigerator when the oil will sohdify. Filter off the crystalline aldoxime at the pump, wash well with cold water, and dry in the air upon filter paper. The yield of veratraldoxime is 88 g. 

Benzaldehyde and veratraldehyde (Section IV, 194) may be similarly converted into the corresponding alcohols. 

Veratraldehyde [120-14-9] M 166.2, m 42-43 . Crystd from diethyl ether, pet ether, CCI4 or toluene. 

Laudanosine contains four methoxyl groups. By exhaustive methyla-tion it yields trimethylamine and laudanosene (tetramethoxy-o-vinyl-stilbene), CH2=CH—C6H2(OCH3)2—CH=CH—C6H3(OCH3),. On oxidation with manganese dioxide and sulphuric acid it furnishes, in addition to the interesting by-product 2 3 6 7-tetramethoxy-9 10-dihydroanthracene, veratraldehyde and 4 5-dimethoxy-2 )3-methyl-... 

The a-isomeride has m.p. 138°, yields a hydrochloride, m.p. 135° [approx., dec.), and a picrate, m.p. 198°. The 3-form occurs in minute needles, m.p. 108-9° (dry), and yields a picrate, m.p. 178-9°. These substances are of interest since their methiodides and methochlorides on treatment with silver oxide or aqueous sodium hydroxide behave abnormally, breaking up into veratraldehyde and 4 5-dimethoxy-2-vinylbenzyldimethylamine (oil picrate, m.p. 158-9° methiodide, m.p. 197-8°) thus — ... 

The opiate alkaloid, papaverine, from Papaver somniferum is an anti-spasmodic, vasodilator, and smooth muscle relaxant. Its total synthesis has been studied since Pictet and Gams early work in 1909 and has since been followed up by various industrial syntheses up till the early 1950s using important industrial commodities as vanillin, acetovanillone, veratraldehyde (methylvanillin), and homoveratric acid as starting materials (see Figure 4.50). Table 4.23 summarizes the results of the five synthetic plans for this natural product. All are convergent... 

Displacement of halogen by ammonia leads to the corresponding amine, probably by an addition-elimination mechanism. There is thus obtained amquinsin (10), a hypotensive agent. Formation of the Shiff base of amquinsin with veratraldehyde gives leniquinsin (11),5 possibly a prodrug. 

A wide-mouth 1-1. Erlenmeyer flask is supported inside a water bath of at least 2-1. capacity so that the bottom of the flask is not in contact with the bottom of the bath. The bath is filled with water at about 15° to cover at least half the height of the flask. The flask is fitted with a moderate-speed stainless-steel propeller-type stirrer, and 350 ml. of nitric acid (sp. gr. 1.4) at 20° is poured into it. Veratraldehyde,2 70 g. (0.42 mole) (Note 2), is crushed at least as fine as rice grains and is slowly added in small portions to the acid. The rate of addition should be such that it requires about 1 hour to add all the aldehyde. It is helpful, although not usually necessary, to add two or three ice cubes to the bath at the start of the nitration. The internal temperature is chocked from time to time and should be held between 18°... 

Valeraldehyde, p28 Valeric acid, p38 Valeronitrile, p35 Valeryl chloride, p45 Vanillic acid, hi43 Vanillin, hl42 Vanillyl alcohol, hl45 Veratraldehyde, d492 Veratric acid, d496 Veratrole, d493 Veronal, d330... 

Activity Assays. The standard activity assay mixture of 3 ml contained about 0.1 U/ml lignin peroxidase, 0.4 mM veratryl alcohol (Fluka, purum >97%) and 0.1M sodium tartrate, pH 3.0. The reaction was started by adding 15 fil of 54 mM H2O2 to make a final concentration of 0.28 mM in the reaction. The production of veratraldehyde was followed by recording the change of absorbance for 12 seconds at 310 nm in a cuvette which was thermostated to 37°C. The reaction was started 24 seconds before the recording. One unit of lignin peroxidase is defined as the amount of enzyme required to oxidize one imol of veratryl alcohol to veratraldehyde in one minute. 

These findings led to the proposition that the veratryl alcohol is degraded via the quinone intermediates (Figure 5) to CO2 through a series of transformations involving lignin peroxidase, perhydroxy radicals and the NADP-dependent aryl alcohol oxidoreductase. Veratraldehyde, the major product of lignin peroxidase catalyzed veratryl alcohol oxidation, is rapidly reduced back to veratryl alcohol it is the further metabolism of the side products of the oxidative process, viz. the quinones and lactones, that drives the overall transformation towards completion (34). 

Dimethoxybenzaldehye or 2,4-Dimethoxybenzaldehyde or Veratraldehyde. Equimolar quantities of phosphorus oxychloride (1 mole = 153 g) and N-methylformanilide (1 mole = 135 g) are placed in a 1 liter, three necked flask and allowed to stand for 45 min. To this mixture is added, over 70 min with stirring, and cooling at 25° 1 mole of 1,4-dimethoxybenzene (to get... 

Dimethoxybenzaldehyde and veratraldehyde use the same procedure, which follows. It should be noted, that the poor yields of these two products can be improved considerably by using 0.2 mole scale instead of 1 mole, as described above. You will have to change the reagent quantities to 0.2 mole also, the reaction times will remain the same as will the temps. 

After the 70 min addition, at 25° with good stirring, is complete, the cooling bath is removed and the mixture is heated, with stirring, at 70° for 18 hours. It is then poured into water and ice and the product is extracted with ether. The extract is shaken with sodium bicarbonate solution, dried and distilled under 21.0 mm of vacuo. Yields veratraldehyde, 12.5 g (38%), 2,5-dimethoxybenzaldehyde, 16%. For a better yield see CA, 44, 6831, b. 

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