Geranyl hydroquinone

The structures of six new geranyl-hydroquinone-derived compounds, from Cordia alliodora, provide additional support for proposed biogenesis in Cordia species (see Vol. 4, p. 69). The isolation of ethuliacoumarin (260) and cycloethuliacoumarin (261) from Ethulia conyzoides suggests an ocimenone (54) biogenetic origin, ... 

The preparation of coenzyme Q usually involves either 2,3-dimethoxy-5-methylbenzoquinone or hydroquinone as the starting material. Treatment of the hydroquinone with geranyl bromide followed by oxidation affords (61, n = 2) (214). A facile and efficient preparation of ubiquinone-10 (61, n = 10) has been developed (215). 

Antiseptic plant-derived phenols include phenol (Phe-OH, hydroxybenzene, carbolic acid), />-cresol (4-methylphenol), catechol (1,2-dihydroxybenzene), resorcinol (1,3-dihydroxybenzene) and pyrogallol (1,2,3-trihydroxybenzene). Other simple phenols with antimicrobial properties include some related to benzoic acid (benzenecarboxylic acid), namely salicylic acid (2-hydroxybenzoic acid), ginkgoic acid (2-hydroxy-6-(pentadec-8-enyl)benzoic acid), gentisic acid (2,5-dihydroxybenzoic acid), pyrocatechuic acid (3,4-dihydroxybenzoic acid) and gallic acid (3,4,5-trihydroxybenzoic acid). Other plant-derived phenol-related compounds include 4-methylcatechol, 1,3-dihydroxy-5-(heptadec-12-enyl)benzene, hydroquinone (1,4-dihy-droxybenzene), 1,4-dihydroxy-2-geranyl (di-isoprenyl)benzene and 4-methoxybenzaldehyde (/>-anisealdehyde). 

To a stirred suspension of 176 mg sodium hydride (60% in oil, 4.4 mmol) in 20 mL THE at room temperature under argon atmosphere was added 0.376 g phenol (4.0 mmol) in portions followed by a catalytic amount of hydroquinone. The mixture was stirred for 0.5 h. HMPA (2 mL) and 0.74 mL geranyl chloride (4.0 mmol) were successively added. The whole mixture was stirred for 1 day. After decomposition of excess sodium hydride with 0.5 niL methanol, the mixture was poured onto ice water and extracted with ether. The combined organic layers were dried, concentrated, and purified by column chromatography on silica gel (hexane-dichloromethane as eluent). 

Compounds Derived by Alkylation with Geranyl-OPP Monoterpene-Derived Compounds of Marijuana Hydroquinone Derivatives in Cordia Species Chemosystematic Use of Monoterpene Chemical Data Chemosystematic Study of Citrus Species Chemosystematic Study of Gymnosperms Chemosystematic Studies in Mints Biological Activity... 

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