| Reference | [1]. ACS Sustain Chem Eng. 2020 Jun 29;8(25):9558-9568. doi: 10.1021/acssuschemeng.0c02840. Epub 2020 Jun 1.<br />
Fully Biobased Superpolymers of 2,5-Furandicarboxylic Acid with Different Functional Properties: From Rigid to Flexible, High Performant Packaging Materials.<br />
Guidotti G(1), Soccio M(1), García-Gutiérrez MC(2), Ezquerra T(2), Siracusa V(3), Gutiérrez-Fernández E(2), Munari A(1), Lotti N(1).<br />
Author information: (1)Civil, Chemical, Environmental and Materials Engineering Department, University of Bologna, Via Terracini 28, 40131 Bologna, Italy. (2)Instituto de Estructura de la Materia IEM-CSIC, Consejo Superior de Investigaciones Científicas, Calle Serrano 121, 28006 Madrid, Spain. (3)Dipartimento di Scienze Chimiche, University of Catania, Viale A. Doria 6, 95125 Catania, Italy.<br />
In the present paper, four fully biobased homopolyesters of 2,5-furandicarboxylic acid (2,5-FDCA) with a high molecular weight have been successfully synthesized by two-stage melt polycondensation, starting from the dimethyl ester of 2,5-FDCA and glycols of different lengths (the number of methylene groups ranged from 3 to 6). The synthesized polyesters have been first subjected to an accurate molecular characterization by NMR and gel-permeation chromatography. Afterward, the samples have been successfully processed into free-standing thin films (thickness comprised between 150 to 180 μm) by compression molding. Such films have been characterized from the structural (by wide-angle X-ray scattering and small-angle X-ray scattering), thermal (by differential scanning calorimetry and thermogravimetric analysis), mechanical (by tensile test), and gas barrier (by permeability measurements) point of view. The glycol subunit length was revealed to be the key parameter in determining the kind and fraction of ordered phases developed by the sample during compression molding and subsequent cooling. After storage at room temperature for one month, only the homopolymers containing the glycol subunit with an even number of -CH2- groups (poly(butylene 2,5-furanoate) (PBF) and poly(hexamethylene 2,5-furanoate) (PHF)) were able to develop a three-dimensional ordered crystalline phase in addition to the amorphous one, the other two appearing completely amorphous (poly(propylene 2,5-furanoate (PPF) and poly(pentamethylene 2,5-furanoate) (PPeF)). From X-ray scattering experiments using synchrotron radiation, it was possible to evidence a third phase characterized by a lower degree of order (one- or two-dimensional), called a mesophase, in all the samples under study, its fraction being strictly related to the glycol subunit length: PPeF was found to be the sample with the highest fraction of mesophase followed by PHF. Such a mesophase, together with the amorphous and the eventually present crystalline phase, significantly impacted the mechanical and barrier properties, these last being particularly outstanding for PPeF, the polyester with the highest fraction of mesophase among those synthesized in the present work.<br />
DOI: 10.1021/acssuschemeng.0c02840 PMCID: PMC8007128 PMID: 33796416<br />
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[2]. Beilstein J Org Chem. 2013 Aug 29;9:1768-73. doi: 10.3762/bjoc.9.205. eCollection 2013.<br />
Activation of cryptic metabolite production through gene disruption: Dimethyl furan-2,4-dicarboxylate produced by Streptomyces sahachiroi.<br />
Simkhada D(1), Zhang H, Mori S, Williams H, Watanabe CM.<br />
Author information: (1)Texas A&M University, Department of Chemistry, College Station, TX 77843, USA.<br />
At least 65% of all small molecule drugs on the market today are natural products, however, re-isolation of previously identified and characterized compounds has become a serious impediment to the discovery of new bioactive natural products. Here, genetic knockout of an unusual non-ribosomal peptide synthetase (NRPS) C-PCP-C module, aziA2, is performed resulting in the accumulation of the secondary metabolite, dimethyl furan-2,4-dicarboxylate. The cryptic metabolite represents the first non-azinomycin related compound to be isolated and characterized from the soil bacterium, S. sahachiroi. The results from this study suggest that abolishing production of otherwise predominant natural products through genetic knockout may constitute a means to "activate" the production of novel secondary metabolites that would otherwise lay dormant within microbial genome sequences.<br />
DOI: 10.3762/bjoc.9.205 PMCID: PMC3778384 PMID: 24062841
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