Dehydrodiconiferyl alcohol

A crude enzyme preparation from Vinca rosea catalyzed the enantioselective coupling of coniferyl alcohol to give rise to an optically active C8-C5 neolignan, dehydrodiconiferyl alcohol, with a ratio of (—)-enantiomer to (+)-enantiomer of 2 1 (Fig. 12.10) [66],... 

Orr JD, Lynn DG (1992) Biosynthesis of dehydrodiconiferyl alcohol glucosides implications for the control of tobacco ceU growth. Plant Physiol 98 343-352... 

Dehydrodiconiferyl alcohol-9 - p-D-glucopyranoside P1SO044 Dotriacontanoic acid Wax Eetuloyl-a-L-arabinofuranosyl(phenyl-... 

Finally, there were recently isolated an optically active phenolic compound, dehydrodiconiferyl alcohol (2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropenyl) - 7-methoxy - 3-benzofuranyl-methanol) (70),192 and a complex 2,3-dihydro-2-phenylbenzofuran, hordanatin A, an antifungal factor 193 it has recently been synthesized,194 and may play a part in the lignification process. 

At a certain stage during the dehydrogenation, the dehydrodiconiferyl alcohol (XVII) produced comprises about 15% of the total lignols formed 22). It arises by combination of Rb (XII) and Rc (XIII). Since it also originates from Rn, it is optically inactive as are all the other lignols and... 

The same chromophore is present in the p-quinonemethide precursors of DL-pinoresinol (twice) and dehydrodiconiferyl alcohol (once). Measurements in a fast-recording ultraviolet spectrometer (Cary apparatus) indicated a half-life of the quinonemethides of about 1 hour (dilute solution in 70% aqueous dioxane at 20°C. and pH 5.5) (5, 18). They may also become stabilized to a small extent by polymerization (see XLIV). Since the quinonemethide (XXI) has no opportunity to become stabilized by intramolecular prototropy, it adds on external electrolytes, particularly hydroxyl compounds and preferably water 31). 

The yield of guaiacylglycerol 0-coniferyl ether (XXII) 31) probably surpasses even pinoresinol (XIX) and dehydrodiconiferyl alcohol (XVII). So far it has not been obtained in crystalline form, possibly because of its labile benzyl alcohol group. A derivative has been obtained in the crystalline state and has also been synthesized 15). Guaiacylglycerol 0-coniferyl ether also occurs to a small extent in spruce cambium and has been isolated from spruce lignin as a crystalline derivative 42). 

Dehydrotriconiferyl alcohol (XLI) (39) is another trilignol whose formation among the intermediates can be explained by interaction of Rb and a corresponding Rc radical of dehydrogenated dehydrodiconiferyl alcohol (XVII). 

Guaiacylglycerol /3-coniferyl-7-dehydrodiconiferyl ether (XLIII) 16) is a tetralignol of the same kind as the last trilignol and originates by addition of preformed dehydrodiconiferyl alcohol (XVII) onto the dimeric quinonemethide (XXI). It is more stable as the trilignol (XLII). 

The structure of the phenylcoumarone (XXII) 26) was derived from analytical and spectral investigation and was confirmed by a synthesis 29) starting from dehydrodiconiferyl alcohol (XXVII). The latter compound (XXVII) was converted by monoperphthalic acid into an epoxide whose side chain was equivalent to that of an arylglycerol. By properly performed acidolysis, the epoxide side chain therefore was converted into the primary ketol structure, and at the same time the hydroxymethyl-substituted phenylcoumaran system see XXVII) was converted into the methyl-substituted phenylcoumarone system of XXII (Figure 8). 

Recently, Freudenberg and co-workers (//) briefly reported the isolation of small amounts of dehydrodiconiferyl alcohol (XXVII) from the methanolysis of wood at room temperature. By this procedure, again, only benzyl aryl ether-linked terminal dimers can be obtained whereas acidolysis liberates (a- and) /3-ether-linked phenylcoumaran systems from the core of the lignin molecule as well. 

A stereocontrolled synthesis of the biologically active neolignan (+)-dehydrodiconiferyl alcohol, which was isolated from several Taxus species, was achieved via Evans asymmetric aldol condensation [58] using ferulic acid amide derived from D-phenylalanine. The reaction steps are shown in Fig. 9. This stereocontrolled reaction is also useful for preparing the enantiomer of (+)-dehydroconiferyl alcohol using chiral auxiliary oxazolidinone prepared from L-phenylalanine. This reaction also enables the syntheses of other natural products that possess the same phenylcoumaran framework. 

The main products of coniferyl alcohol dimerization by peroxidase (Scheme XI) are the neolignans, pinoresinol (XXVII), dehydrodiconiferyl alcohol (XXVni) and guaiacylglycerol-P-O-coniferyl alcohol ether... 

The formation of Cp—Car bonds is illustrated by the generation of dehydrodiisoeugenol (286) from ( )-isoeugenol (257), enzymically with a mushroom juice (45%) yield, with horseradish peroxidase (65%), ° with iron(III) chloride (53%), by photooxidation (20%) and by (-)-a-phenylethylamine-copper(ll) nitrate (21%). In the last case a low enantiomeric excess was recorded. Coniferyl alcohol can be oxidized to dehydrodiconiferyl alcohol (287) with various enzyme oxidases. The cis... 

Dakin oxidation 419, 420 Dakin rearrangement 799, 800 Dehalogenation 1098-1100 Dehydrodiconiferyl alcohol, mass spectrum of... 

Only one specie, H. lawsoniae has been found to contain lignans. Novel sesquilignans named as hedyotol A, -B, -C and -D (66-69) [16] and their acetyl derivatives, (+)-pinoresinol, (+) medioresinol, (+)-syringaresinol, (-)-dehydrodiconiferyl alcohol, (70-73) as well as the novel dilignans, hedyotisol A, -B and -C (74-76) have been isolated from this plant (Table 7) [17]. 

An epimeric pair of dehydrodiconiferyl alcohol P-o-gly-cosides (23, 24) from crown gall Agrobacterium tumefa-ciens) tumors in transformed Catharanthus roseus cultures has been shown to promote cell division and replace the cytokinin requirement in tobacco cells (Fig. 8.10) (Binns et al., 1987 Lynn et al., 1987). 

Constit. of Vladimiria souliei. Obt. as a mixt. with Vladinol E (see Dehydrodiconiferyl alcohol, D-20016). (2R Syform [126253-41-6]... 

Benzyl 4,6-O-benzylidene-a-D-glucopyranoside, in B-30019 Benzyl 4,6-0-benzylidene-y -D-glucopyranoside, in B-30019 Dehydrodiconiferyl alcohol, D-20016... 

Dehydrobrucein A, in D-10029 Dehydrodiconiferyl alcohol 3 -0-/ -D-Glucopyranoside, in D-20016 Dehydrodiconiferyl alcohol 4"-0-/ -d-Glucopyranoside, in D-20016 Dehydro coniferyl alcohol S-O-fi-D-Glucopyranoside, in D-20016... 

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