Protocatechu aldehyde

It was first artificially prepared by Tiemann from the glucoside coni-ferin, which occurs in the cambium of various coniferous woods. The constitution of vanUlin is that of methyl protocatechuic aldehyde—... 

This body, also known as piperonal, is a white crystalline compound possessing a powerful odour of heliotrope. It is the methylene eEier of protocatechuic aldehyde, of the constitution—... 

Phenol aldehydes are generally pleasant-smelling products. Some of them are particularly important as fragrance and flavor materials. Anisaldehyde and certain derivatives of protocatechu aldehyde (3,4-dihydroxybenzaldehyde) are well-known representatives. The monomethyl ether of protocatechu aldehyde, vanillin, is perhaps the most widely used flavor material. Other important derivatives of this aldehyde are veratraldehyde (dimethyl ether) and heliotropin (formaldehyde acetal derivative) they are not only used as fragrance and flavor substances, but also are intermediates in many industrial processes. 

Capsicum frutescens (immobilised) Protocatechuic aldehyde, caffeic acid Vanillin, capsaicin [23]... 

Ilex chinensis Sims Shi Ji Qing (Wintergreen holly) (leaf) Protocatechuic acid, protocatechuic aldehyde, ursolic acid, tannic acid.33 Treat angina pectoris, thrombophlebitis, extremity ulceration. 

Rao, S.R. and Ravishankar, G.A. (2000b) Biotransformation of protocatechuic aldehyde and caffeic acid to vanillin and capsaicin in freely suspended and immobilized cell cultures of Capsicum frutescens. Journal of Biotechnology 76, 137-146. 

SYNS 3,4-BENZODIOXOLE 5-CARBOXALDEHYDE 3,4-DIHYDROXYBENZALDEHYDE METHYLENE KETAL DIOX i METHYLENE-PROTOCATECHUIC ALDEHYDE FEMANo. 2911 HELIOTROPIN 3,4-METH iTENE-DIHYDROXYBENZALDEHYDE 3,4-METHYLENEDIOXYBENZALDEHYDE PIPERON-ALDEHYDE PIPERONYL ALDEHYDE PROTO-CATECHUIC ALDEHYDE METHYLENE ETHER... 

DIOXYETHYLENE ETHER see DVQOOO DIOXYMETHYLENE-PROTOCATECHUIC ALDEHYDE see PIW250... 

Protocatechuic Aldehyde.—A di-phenol aldehyde, viz., the 3-4-di-hydroxy benzaldehyde, is known as protocatechuic aldehyde because it yields protocatechuic acid on oxidation. 

Vanillin.—Two very important essential oil constituents are ether derivatives. One of these is vanillin, the chief constituent of vaniUa beans from which vanilla extract is made, and the other is heliotropin, also known as piperonal, which has the odor of heliotrope flowers. Vanillin is the mono-methyl ether of protocatechuic aldehyde, the methoxy... 

Just as protocatechuic aldehyde may be synthesized by the Reimer-Tiemann or Gattermann-Koch reactions from the -di-phenol pyro-catechinol, so vanillin may be made by the same reactions from the mono-methyl ether of pyrocatechinol, Le.f guaiacol (p. 621). 

Heliotropin may be prepared from protocatechuic aldehyde by the action of methylene iodide, CH2I2, the yield, however, being small. 

Heliotropin is prepared commercially by the synthesis given above from safrole through iso-safrole. It is used in perfumes on account of its very pleasant odor of heliotrope flowers. It forms crystals, m.p. 37°, b.p. 263°. By boiling with water it hydrolyzes and yields protocatechuic aldehyde just as vanillin does. It also yields oximes and hydrazones which are characteristic. 

Protocatechuic Acid.—One of the di-hydroxy benzoic acids is related to vanillin, which we have already studied. The acid is known as protocatechuic acid, and derives its name from the fact that it may be obtained from a gum or resin, known as gum catechin by fusion with potash, i.e. by heat and oxidation in presence of an alkali. A large variety of plant products including alkaloids essential oils, gums, resins and tannins yield this acid. The following may be mentioned gum catechin, gum benzoin, guaiac resin, myrrh, piperine or piperic acid, vanillin, cafe-tannic acid. These natural sources at once suggest a relationship to vanillin (p. 661) and heliotropin (p. 662). It is the acid corresponding to protocatechuic aldehyde, 3-4-di-hydroxy benzal-dehyde (p. 661), which explains the relationship just mentioned. Its constitution, is then ... 

The reaction was carried out as in Example 1(f) using protocatechuic aldehyde (13.8 w.) and the product was isolated from the reaction mixture hy steam distillation. Piperonal was isolated in 61% yield and was identified by comparison with an authentic sample. 

CAS 121-33-5. (CH30)(0H)C6H3CH0. The methyl ether of protocatechuic aldehyde. 

SHUANGDAN granule Protocatechuic aldehyde, paeonol, danshensu, salvianolic acid B MEKC Eour-factor CCD (Borate), (phosphate), (SDS),ACN % Modified chromatographic exponential function, resolution of three mark peaks, mobility time of final peak (45)... 

Ortho and para hydroxybenzaldehydes, vanillin, ethyl vanillin, protocatechu-aldehyde, veratraldehyde and piperonal are the most important products. 

H.55) Benzaldehyde, 3,4-dihydroxy-, 3,4-dihydroxybenzaldehyde, l,2-dihydroxy-4-formylbenzene, protocatechuic aldehyde 139-85-5]... 

Friedrich (1976) suggested formation by methylation of protocatechuic aldehyde (H.55), the corresponding glycoside being the immediate precursor. Tressl et al. (1976, 1979b) identified vanillin as a thermal decomposition product of ferulic acid (H.87), formed by oxidation of 4-vinylguaiacol (H.36). 

Propylowy alkohol 3169 Protocatechuic aldehyde ethyl ether 1706... 

Thus, tyramine and protocatechuic aldehyde -or derivatives of the latter- are logical components for the biosynthesis of the precursor norbelladine (85). This reaction occupies a pivotal position since it represents the entry of primary metabolites into a secondary metabolic pathway. The junction of the amine and the aldehyde results in a Schiff s base, two of which have been isolated up to now craugsodine (114) and isocraugsodine (115). The existence of Schiff s bases in nature as well as their easy conversion into the different ring-systems of the Amaryllidaceae alkaloids allow the presumption that the initial postulate about this biosynthetic pathway was correct. 

The biological conversion of protocatechuic aldehyde into lycorenine (31), which proceeds via 0-methylnorbelladine (88) and norpluviine (12), first involves a reduction of... 

Starting Molecule 2-Nitro-protocatechuic aldehyde Reagents Nitroethane, acetic anhydride Product ll 2-Dinitro-4,5-dlacetoxy-S-methylstyrene Reference (Partington 1948)... 

Methyl-protocatechuic aldehyde—Vanillin— CbH s(OH)(OCHs> COH—is the odoriferous, principle of vanilla. It is produced artificially by oxidation of ooniferin, CigHi,Oe, a glucosid occurring in coniferous plants. It crystallizes in needles, fuses at 80 (170° F.) is sparingly soluble in water, readily soluble in alcohol or ether. It has a pungent taste, and a faint odor of vanilla, the latter more marked, when the substance is heated. On exposure to air it becomes partially oxidized to vanillic acid CsHsO<. 

Piperonal possesses the odor of heliotrope, and is used in perfumery. It may be prepared by treating an alkaline solution of protocatechuic aldehyde with methylene iodide — ... 

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