Guaiaretic acid

Guaiaretic acid, nor-dihydro, 3 -0-methyl PJLTOI8 l LT007... 

P-Isoasarone in oil from root calamus <10%, americanus 0%, angustatino >80% Nordihydro-guaiaretic acid in leaves 0.03 >%0.6% UP As in root and leaves Teucrin A in aerial parts... 

The inclusion of fatty acids is a surprise, but maybe not for that called guaiaretic acid, nordihydro, better known as NDGA or nordihydroguaiaretic acid. It is an ingredient in chaparral or creosote bush, and was formerly used commercially as an oxidation inhibitor in various apphcations (note that oxidation inhibitors are viewed as beneficial for a number of purposes, including cancer suppression). 

Pycnanthus angolensis, a plant used in Cameroon as a vermifuge, produced dihydro-guaiaretic acid (187) which showed low activity (LC50... 

This is an antioxidant in topical preparations. Roed-Petersen and Hjorth (1976) reported six cases of contact allergy with a lanolin cream containing nordihidro-guaiaretic acid (NDGA) as the culprit in three cases. 

Roed-Petersen and Hjort (1976) and Fischer (1976) have demonstrated contact dermatitis to antioxidants which are hidden sensitizers in topical medications and in foods. Antioxidants are usually phenols such as BHA, BHT, nordihydro-guaiaretic acid (NGDA), and gallate esters. Burckhardt and Fierz (1964) and Brun (1964, 1970) described contact dermatitis from gallate esters in margarine. a-Tocopherol has been used extensively in food and topical applications but only a few cases of contact dermatitis have been reported (Brodkin and Bleiberg 1965 Aeling et al. 1973 Minkin et al. 1973 Marzulli and Maibach 1974 Roed-Petersen and Hjort 1976). 

Guaiaretic acid (constitues about 10% of the resin of Guaiacum officinale L.)... 

Guaiaretic Acid (i- 4-ItydToxy-Z-methoxy-bemyl - 3 - [4 - hydroxy - Z-n hoxybenzylidenel-but-... 

Gravelliferone 8-Methoxy, in G-60037 Guaiaretic acid, G-70033 Hebeclinolide, H-60009 Isobharangin, 1-80048 Polemannone, P-60166 Sirutekkone, S-70048 Vernoflexin, in Z-60001 Zaluzanin C Angeloyl, in Z-60001... 

Chart 1. Determination of the absolute configuration of (— )-guaiaretic acid (1.1a)... 

Subsequent to the isolation of partially 0-demethylated dihydro-guaiaretic acid (1.3c), it was proposed to call this compound or-dihydro-guaiaretic acid, and 1.3b ftwwor-dihydroguaiaretic acid (63). Adoption of this proposal would lead to confusion, in view of the voluminous literature on NDGA (1.3b) (see Section XIII). 

Resin. II. Synthesis of dl-Guaiaretic Acid Dimethyl Ether. J. Chem. Soc. (London) 1934, 1423. 

Additional support for the theory of lignin formation by dehydrogenation of Cg. C3 cinnamyl alcohol precursors is often derived from the widespread occurrence of dimers of the Cg. C3 carbon skeleton, joined by the -carbon atoms in the side chains, in woods and wood exudates. This group of natural products— lignans—has long been recognised and has stimulated a considerable research interest - Typical members of this class are for example (—)-guaiaretic acid (86) and (+)-pinoresinol (87), the... 

The lignans consist of two phenylpropanoid molecules joined by carbon-carbon bonds between the middle carbon atoms of the side chain. Guaiaretic acid, a constituent of gum guaiacum, is a compound of this type. 

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