Homoveratric acid

To the above aqueous solution contained in a 2-1. widemouthed Erlenmeyer flask, is added 85 cc. of 40 per cent sodium hydroxide solution. The flask is equipped with a mechanical stirrer and is cooled in an ice-salt mixture. With stirring, 75 cc. of 30 per cent hydrogen peroxide (Merck s Superoxol ) 

The inner level is kept below that of the oil in order to avoid the otherwise uncontrollable bumping of the solution. 

4-Dimethoxyphenylpyruvic acid can be isolated from this solution in the following way (J. S. Buck and W. S. Ide). The aqueous solution of the sodium salts is saturated with sulfur dioxide, while the temperature is maintained below 40°. The benzoic acid precipitates and is filtered off with suction and washed with a small quantity of water. The filtrate and washings are placed in a 3-I. round-bottomed flask provided with a mechanical stirrer and heated to boiling. Concentrated hydro- 

An alternative procedure for the preparation of homoveratric acid (J. S. Buck and W. S. Ide) consists in isolating the pyruvic acid and subjecting it to the oxidation process given in the second paragraph of part A. This variation obviates the esterification process but in the hands of the checkers did not prove as satisfactory as the one described. 

Large quantities of carbon dioxide are evolved during the addition of the acid. 

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Dimethoxyphenyl acetic acid (homoveratric acid) [93-40-3] M 196.2, m 97-99 , pK 4.33. Crystd from water or benzene/ligroin. 

C5H12N2 505-(56-S) see Fasudil homoveratric acid (C10H12O4 93-40-3) see Papaverine homoveratronitrile... 

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... 

Hexyl methyl ketone, o36 Hexyl propyl ketone, d20 Hippuric acid, b70 Homocysteine, a200 Homopiperidine, h48 Homoveratric acid, d513 Homoveratrylamine, d517 Hydroacrylonitrile, hi 73 2-Hydrazinoethanol, hi 25... 

Pearson and Walavalkar (57) reported a facile approach to the synthesis of ( )-tyloporine (288) based on an intramolecular cycloaddition of an azide with an co-chloroalkene (Scheme 9.57). The required (Z) alkene 285 was prepared from homoveratric acid (284). Treatment of the chloro alkene 285 with sodium azide... 

Acylation of homoveratric esters 51 leads to the stable 3-alkoxy-substituted cations 52, whereas the use of homoveratric acid 51 (R = H) gives the unstable 3-acyloxy-substituted salts 53, which are easily hydrolyzed to ring-opened ketoacids 54 [70KGS(2)200]. 

Upon acylation of some benzyl carbonyl compounds (25, R = H, Me 51, R = OH) dibenzo[a,tropylium salts 65 have been isolated in low yields (5-15 %) along with the major products, 2-benzopyrylium salts. Veratryl acetone 25 (R = Me) as well as homoveratric aldehyde 25 (R = H) (or carboxonium ions 31 which are formed from them) may undergo an oxidative a-cleavage, resulting in the benzyl cation 64. The formation of the same cation from homoveratric acid 51 is the result of decarbonylation of the acylium ion 63. Further interaction of the benzyl cation 64 with the substrate, followed by cyclization and oxidation, results in the polycyclic tropylium salts 65 (82ZOR589). 

Diarylbenzo[c]pyrylium salts 76 are formed by rearrangement in PPA of o-benzhydryl homoveratric acids 73 (81ZOR440). 

Hexyl methyl ketone, o34 Hexyl propyl ketone, dl6 Hippuric acid, b71 Histamine, i8 Homocysteine, a204 Homopiperidine, h51 Homoserines, al88, al89 Homoveratric acid, d447 Homoveratrylamine, d451... 

B) Homoveratric Acid.—In a 500-cc. round-bottomed flask are placed 250 cc. of 10 per cent sodium hydroxide solution and 76 g. (0.36 mole) of methyl homoveratrate. The flask is fitted with a reflux condenser and the mixture is boiled gently. The saponification proceeds rapidly and the ester layer disappears after about ten minutes. The mixture is refluxed gently for... 

Homoveratric acid has been prepared by the methylation of homoprotocatechuic acid1 and of homovanillic acid2 with methyl iodide, and from veratric aldehyde through the azlactone and 3,4-dimethoxyphenylpyruvic acid.3 The procedure given here is adapted from that last mentioned and from that used for the preparation of -methoxyphenylacetic acid.4... 

A mixture of homoveratric acid (49 g), anhydrous sodium acetate (20.5 g) and acetic anhydride (83 mL) was refluxed for 4 hours, cooled, added to 500 mL. of ice-cold water and stirred for 15 minutes. The resulting reddish bottom layer was separated and retained. The remaining aqueous layer was extracted with two 100 mL. quantities of toluene, and the toluene extracts were combined with the reddish liquid and washed successively with five 100 mL. quantities of IN sodium hydroxide solution, followed by two 100 mL. quantities of water. The washed product was then filtered through a plug of glass wool and fractionally distilled to remove the toluene and water impurities. The product, 3,4-dimethoxyphenylacetone, was collected at 115°C to 125°C at about 0.4 mm Hg. This product was a pale yellowish oil and was obtained in a yield of 16 g (33% of theoretical yield). 

Preparation of Homoveratric acid (3,4-Dimethoxy-phenylacetic acid)... 

Cleanse of a-keto acids and a-dikelones. The cleavage of an a-keto acid is the terminal step in a synthesis of homoveratric acid (4) from veratraldehyde (1), via the azlactone (2). Alkali cleaves the azlactone ring with elimination of benzoic... 

The structure proposed for septicine (20), the dehydroindolizidine constituent of Ficus septica, has recently been confirmed by two independent syntheses. The first synthesis proceeded from veratraldehyde, which was condensed with homoveratric acid to give the unsaturated acid (21) this was then converted into the primary chloride (22) by standard methods. Alkylation of L-prolinol with this chloride gave the amino-alcohol (23), which was converted into its O-methanesulphonate ester. Reaction of this ester with sodium hydride in anhydrous... 

Homoveratric Acid (is, 31) From veratroyl chloride by treatment with... 

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