Vanillal

Propanidid. Propanidid [1421-14-3] (Epontol), C gH2yNO, (7) a derivative of the propyl ester of homo vanillic acid, has been in clinical use in Europe for a number of years. Its main advantage is rapid onset of action and a fast recovery which, like etomidate, is because of rapid metaboHsm by esterases rather than redistribution (108). Excretion is rapid 75 to 90% of the dmg is eliminated as metaboUtes within two hours. Propanidid side effects include hypotension, tachycardia, and hyperventilation followed by apnea, as well as excitatory side effects such as tremor and involuntary muscle movement (109). 

On distillation at atmospheric pressure, vanillin undergoes partial decomposition with the formation of pyrocatechol. This reaction was one of the first to be studied and contributed to the elucidation of its stmcture. Exposure to air causes vanillin to oxidize slowly to vanillic acid. When vanillin is exposed to light in an alcohoHc solution, a slow dimerization takes place with the formation of dehydrodivanillin. This compound is also formed in other solvents. When fused with alkaU (eq. 3), vanillin (I) undergoes oxidation and/or demethylation, yielding vanillic acid [121 -34-6] (8) and/or protocatechaic acid (2). 

This type of cement has been further improved by the substitution of -hexyl van ill ate [84375-71-3] and similar esters of vanillic acid [121 -34-6] and/or syringic acid [530-57 ] for eugenol (93—95). These substituted cements are strong, resistant to dissolution, and, unlike ZOE and EBA cements, do not inhibit the polymerization of resin-base materials. Noneugenol cements based on the acid—base reaction of zinc and similar oxides with carboxyhc acids have been investigated, and several promising types have been developed based on dimer and trimer acids (82). 

Karrer and Schmid have examined the water-soluble constituents in poppy straw after extraction of the alkaloids, and have recorded the presence of -hydroxybenzaldehyde, vanillin, -hydroxystyrene, meconin and the following acids fumaric, dZ-lactic, benzoic, -hydroxycinnamic, p-hydroxybenzoic, 2-hydroxycinchoninic, vanillic, phthalic, hemipinic and m-hemipinic, with a more highly unsaturated, carboxylic acid J, b.p. 170-570-02 mm., and three unidentified substances Fa , m.p. 271-2° Wx, m.p. 310° (dec.) and Q, m.p. 260° the two latter are free from nitrogen and contain no methoxyl. 

Therapeutic Function Central and respiratory stimulant Chemical Name N,N-Diethyl-4-hydroxy-3-methoxybenzamide Common Name Vanillic acid diethylamide Structural Formula coxtc HjIj... 

Mobile phase front HomovanilUc acid Vanillic acid... 

Fig. II Fluorescence scan of a chromatogram track with SOO ng each of noradrenaline (1), adrenaline (2), serotonin (3), vanilmandelic add (4), 5-hydroxyindoleacetic add (6), homovanillic acid (7) and vanillic acid (8) together with 230 ng creatinine, all per chromatogram zone measurement at X(3,c = 313 nm and > 390 nm (cut off filter FI 39 (A)), X = 365 nm and Xj, >430 nm...

It is possible to replace the vanillin in the reagent by 4-dimethylaminobenzaldehyde, 4-hydroxybenzaldehyde, salicylaldehyde, /n-anisaldehyde, cinnamaldehyde, 4-hydioxy-benzoic acid or vanillic acid [3]. However, the range of colors obtained is not so broad. 

Studies by Hudson et al, (2000) have demonstrated the presence of eight polyphenols in rice bran by using high-pressure liquid chromatography. They are protocatechuic acid, p-coumaric acid, ferulic acid, sinapic aci vanillic acid, caffeic acid, which is a methoxycirmamic acid derivative, and tricin. The effect of these polyphenols on cell viability and on the colony-forming ability of human-derived MDA MB 468 and HBL 100 breast cells, colon-derived SW 480 and human colonic epithelial cells was assessed. These authors concluded that rice bran polyphenols have putative cancer chemopreventive properties. 

Primary structure analysis of phenylphosphate carboxylase of T. aromatica is performed in detail, to clarify the reaction mechanism involving four kinds of subunits. The a, (3, y, 8 subunits have molecular masses of 54, 53, 18, and lOkDa, respectively, which make up the active phenylphosphate carboxylase. The primary structures of a and (3 subunits show homology with 3-octaprenyl-4-hydroxybenzoate decarboxylase, 4-hydroxybenzoate decarboxylase, and vanil-late decarboxylase, whereas y subunit is unique and not characterized. The 18kDa 8 subunit belongs to a hydratase/phosphatase protein family. Taking 4-hydroxybenzoate decarboxylase into consideration, Schiihle and Fuchs postulate that the a(3y core enzyme catalyzes the reversible carboxylation. ... 

The total phenolic content in XRPP was 1.10%. The major components were found to be p-hydroxybenzoic acid (0.44%), vanillin (0.19%), syringic acid (0.13%), and syringaldehyde (0.13%). The contents of p-hydroybenzaldehyde, vanillic acid and ferulic acid were 0.032, 0.015 and 0.020%, respectively. Gallic acid, protocatechuic acid and cinnamic acid were detected in trace amounts. 

Pometto AL, JB Sutherland, DL Crawford (1981) Streptomyces setonii catabolism of vanillic acid viaguaiacol and catechol. Can J Microbiol 27 636-638. 

It is also important to appreciate that an organism that can degrade a given substrate under conditions of nitrate dissimilation may not necessarily display this potential under aerobic conditions. For example, a strain of Pseudomonas sp. could be grown with vanillate under anaerobic conditions in the presence of nitrate but was unable to grow under aerobic conditions with vanillate. 

In contrast, cells grown anaerobically with nitrate and vanillate were able to oxidize vanillate under both aerobic and anaerobic conditions. The cells were also able to demethylate a much wider spectrum of aromatic methoxy compounds under anaerobic conditions than under aerobic conditions (Taylor 1983). Such subtleties should be clearly appreciated and taken into consideration in evaluating the degradative potential of comparable organisms under different physiological conditions. 

Taylor BE (1983) Aerobic and anaerobic catabolism of vanillic acid and some other methoxy-aromatic compounds by Pseudomonas sp. strain PN-1. Appl Environ Microbiol 46 1286-1292. 

FIGURE 4.6 Biotransformation of 4,5,6-trichloroguaiacol by Rhodococcus sp. during growth with vanillate. 

Ander P, K-E Eriksson, H-S Yu (1983) Vanillic acid metabolism by Sporotrichium pulverulentum evidence for demethoxylation before ring-cleavage. Arc/ MicrobioZ 136 1-6. 

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