2983-65-5Relevant articles and documents
Enzymatic Specific Production and Chemical Functionalization of Phenylpropanone Platform Monomers from Lignin
Ohta, Yukari,Hasegawa, Ryoichi,Kurosawa, Kanako,Maeda, Allyn H.,Koizumi, Toshio,Nishimura, Hiroshi,Okada, Hitomi,Qu, Chen,Saito, Kaori,Watanabe, Takashi,Hatada, Yuji
, p. 425 - 433 (2017)
Enzymatic catalysis is an ecofriendly strategy for the production of high-value low-molecular-weight aromatic compounds from lignin. Although well-definable aromatic monomers have been obtained from synthetic lignin-model dimers, enzymatic-selective synthesis of platform monomers from natural lignin has not been accomplished. In this study, we successfully achieved highly specific synthesis of aromatic monomers with a phenylpropane structure directly from natural lignin using a cascade reaction of β-O-4-cleaving bacterial enzymes in one pot. Guaiacylhydroxylpropanone (GHP) and the GHP/syringylhydroxylpropanone (SHP) mixture are exclusive monomers from lignin isolated from softwood (Cryptomeria japonica) and hardwood (Eucalyptus globulus). The intermediate products in the enzymatic reactions show the capacity to accommodate highly heterologous substrates at the substrate-binding sites of the enzymes. To demonstrate the applicability of GHP as a platform chemical for bio-based industries, we chemically generate value-added GHP derivatives for bio-based polymers. Together with these chemical conversions for the valorization of lignin-derived phenylpropanone monomers, the specific and enzymatic production of the monomers directly from natural lignin is expected to provide a new stream in “white biotechnology” for sustainable biorefineries.
Rh-Catalyzed Decarbonylative Addition of Salicylaldehydes with Vinyl Ketones: Synthesis of Taccabulins A–E
Rao, Maddali L. N.,Ramakrishna, Boddu S.
, p. 7545 - 7554 (2019/12/15)
A rhodium-catalyzed decarbonylative addition of salicylaldehydes with vinyl ketones was developed to synthesize o-hydroxydihydrochalcones (2-hydroxyphenethyl ketones). These decarbonylative addition reactions afforded various functionalized o-hydroxydihydrochalcones in moderate to good yields with broad functional group tolerance and selectivity. This method was also applied further in the divergent synthesis of dihydrochalcone derived taccabulins A–E.
Synthesis of the natural product descurainolide and cyclic peptides from lignin-derived aromatics
Ojo, O. Stephen,Nardone, Brunello,Musolino, Stefania F.,Neal, Andrew R.,Wilson, Liam,Lebl, Tomas,Slawin, Alexandra M. Z.,Cordes, David B.,Taylor, James E.,Naismith, James H.,Smith, Andrew D.,Westwood, Nicholas J.
supporting information, p. 266 - 273 (2018/01/17)
Alternative sources of potential feedstock chemicals are of increasing importance as the availability of oil decreases. The biopolymer lignin is viewed as a source of useful mono-aromatic compounds as exemplified by the industrial scale production of vanillin from this biomass. Alternative lignin-derived aromatics are available in pure form but to date examples of the use of these types of compounds are rare. Here we address this issue by reporting the conversion of an aromatic keto-alcohol to the anti- and syn-isomers of Descurainolide A. The key step involves a rhodium-catalyzed allylic substitution reaction. Enantio-enriched allylic alcohols were generated via an isothiourea-catalyzed kinetic resolution enabling access to both the (2R,3R) and (2S,3S) enantiomers of anti-Descurainolide A. In addition we show that the lignin-derived keto-alcohols can be converted into unnatural amino acid derivatives of tyrosine. Finally, these amino acids were incorporated into cyclic peptide scaffolds through the use of both chemical and an enzyme-mediated macrocylisation.
