Achieving Complexity at the Bottom. 2,6-Bis(arylidene)cyclohexanones and Anthocyanins: The Same General Multistate of Species.

As in supramolecular chemistry, complexity could also be achieved through a bottom-up approach. Anthocyanins and related compounds such as the compound ()-6-(dimethylamino)-4-(4-(dimethylamino)-2-hydroxybenzylidene)-1,2,3,4-tetrahydroxanthylium chloride (), here reported, exhibit this type of complexity. The thermodynamics and kinetics of the complex multistate of species of compound were studied by conventional and stopped-flow UV-visible spectrophotometry as well as by NMR.

Biodegradable Oligoesters of ε-Caprolactone and 5-Hydroxymethyl-2-Furancarboxylic Acid Synthesized by Immobilized Lipases.

Following the latest developments, bio-based polyesters, obtained from renewable raw materials, mainly carbohydrates, can be competitive for the fossil-based equivalents in various industries. In particular, the furan containing monomers are valuable alternatives for the synthesis of various new biomaterials, applicable in food additive, pharmaceutical and medical field. The utilization of lipases as biocatalysts for the synthesis of such polymeric compounds can overcome the disadvantages of high temperatures and metal catalysts, used by the chemical route.

Biocatalytic Route for the Synthesis of Oligoesters of Hydroxy-Fatty acids and ϵ-Caprolactone.

Developments of past years placed the bio-based polyesters as competitive substitutes for fossil-based polymers. Moreover, enzymatic polymerization using lipase catalysts has become an important green alternative to chemical polymerization for the synthesis of polyesters with biomedical applications, as several drawbacks related to the presence of traces of metal catalysts, toxicity and higher temperatures could be avoided. Copolymerization of ϵ-caprolactone (CL) with four hydroxy-fatty acids (HFA) from renewable sources, 10-hydroxystearic acid, 12-hydroxystearic acid, ricinoleic acid, and 16-hydroxyhexadecanoic acid, was carried out using commercially available immobilized lipases from Candida antarctica B, Thermomyces lanuginosus, and Pseudomonas stutzeri, as well as a native lipase.