Laccase-catalyzed oxidative phenolic coupling of vanillidene derivatives

Renewable (semi)aromatic polyesters from symmetrical vanillin-based dimers

“…13,14,15,16,17,18,19,20,21,22,23 Recently, with the increasing interest on renewable resources, several bio-based polymers were produced from vanillin or its derivatives. 44 Also employing laccase from Trametes versicolor we recently developed an efficient enzymatic C-C coupling process -with a high yield and a high selectivity-yielding pure dimers of vanillin and some other phenol substrates. 24 Meier and coworkers also reported the synthesis of 100% bio-based polymers from vanillin and vegetable oil derivatives by acyclic diene metathesis polymerization (ADMET), thiol-ene addition and polycondensation.…”

The Amaryllidaceae alkaloids: biosynthesis and methods for enzyme discovery

“…The P450s CYP81Q1, CYP719A1, CYP719A13, CYP719A14, DesC, and KtnC have been shown to catalyze phenol-phenol coupling reactions and are proposed to act by a diradical mechanism (Ikezawa et al, 2003; Ono et al, 2006; Díaz Chávez et al, 2011; Mazzaferro et al, 2015). Other enzyme groups noted for their ability to perform phenol-phenol’ coupling reactions are laccases and peroxidases (Schlauer et al, 1998; Constantin et al, 2012). In the Amaryllidaceae, two forms of methylation are common: O -methylation and N -methylation.…”

“…pseudonarcissus (Kilgore et al, 2014). The three common phenol-phenol’ coupling reactions that follow require the same biochemistry to operate and are likely catalyzed by cytochrome P450 enzymes, laccases, or peroxidases (Schlauer et al, 1998; Ikezawa et al, 2003; Ono et al, 2006; Díaz Chávez et al, 2011; Constantin et al, 2012). The extensive work studying the biosynthesis of the derivatives generated from phenol-phenol’ coupling products has been reviewed recently and is beyond the scope of this review (Kornienko and Evidente, 2008; Bastida et al, 2011; Jin, 2013; Takos and Rook, 2013).…”

Enantioselective Phenol Coupling by Laccases in the Biosynthesis of Fungal Dimeric Naphthopyrones

“…Laccases are copper-dependent one-electron oxidases that act on phenolic compounds,generating phenoxy radicals that undergo subsequent coupling reactions,including CÀC, CÀO, and CÀNb ond formations.T ypically,t he outcome of these downstream reactions is not controlled by the laccase,t hus leading to amixture of regio-and stereoisomeric products. [1][2][3][4] Recent research on polyketide dimerization in fungi led to the discovery of regioselective laccases. [5,6] In these examples,the polyketide monomers possess several activated positions,o f which only one is selected for coupling by adistinct laccase.In contrast to inherent regioselectivity,e nantioselectivity has only been found when laccases were combined with other proteins.…”

“…[11][12][13][14][15] Thea rchetype is ustilaginoidin A ( 1), which is composed of two identical g-naphthopyrone moieties (Figure 1). Theo ther congeners differ from ustilaginoidin A( 1)b yD 2 double-bond saturation, methylation at position 3, or ac ombination of the two as in chaetochromin A ( 2). Given that they possess three possible positions for C À C bond formation (positions 7, 9, and 10), monomeric gnaphthopyrones can theoretically be coupled to six regioisomeric dimers through oxidative phenol coupling.H owever, exclusively 9,9'-coupled dimers are found in ustilaginoidin producers,s ot he coupling was expected to proceed in ar egioselective manner.…”