Ovine β-lactoglobulin has been isolated from whey fraction of sheep milk and crystallized. The high-resolution structures of two crystal forms (triclinic and trigonal) obtained at pH 7.0 have been determined revealing that ovine protein, similarly to its bovine analog, is dimeric. Access to the binding site located in the eight-stranded antiparallel β-barrel in both structures is blocked by the EF loop that has been found in closed conformation. Similarly to bovine lactoglobulin (BLG), conformation of the EF loop is stabilized by hydrogen bond between Glu89 and Ser116 indicating that Tanford transition might occur with the same mechanism. The substitution at six positions in relation to the most abundant isoform B of BLG also affects the distribution of electrostatic potentials and the total charge.

Direct cross‐aldol reactions of a pyruvate ester with chiral aldehydes, mediated by purely organic catalysts, is described as a crucial step in the synthesis of ulosonic acids. Cinchona alkaloids containing a tertiary amine group efficiently promote direct aldol reactions of a sterically hindered pyruvate ester with various sugar aldehydes. The pyruvic acid ester can be directly used as chemical equivalent of PEP (phosphoenolpyruvate) in imitation of the synthetic principle used in nature. The appropriate combination of a chiral aldehyde with a chiral catalyst allows the flexible preparation of anti‐ or syn‐configured aldols, as desired. As a result, concise syntheses of diverse six‐, seven‐, eight‐, and nine‐carbon ulosonic acid esters are described, by using a biomimetic three‐carbon chain elongation of various sugar aldehydes. Consequently, short and practical syntheses of several ulosonic acids, including three important naturally occurring sugars – 3‐deoxy‐d‐erythro‐hex‐2‐ulosonic acid (KDG), 3‐deoxy‐d‐manno‐oct‐2‐ulosonic acid (KDO), and the rare 3‐deoxyglucosone (3DG), in good overall yields are presented.

Ac hiral dinuclear zincc omplexc an effectively catalyse the direct aldol reactions of pyruvic acid ester with various chiral sugar aldehydes,t hus functionally mimicking the pyruvate-dependent type II aldolases.A pplication of sterically hindered aryl estersa llows for the elusive aldolr eactiono ft he pyruvate donor with controlled anti-selectivity en route to the shorta nd efficient synthesis of 3-deoxy-2-ulosonic acids.Pyruvic acid ester is here used as achemical equivalent of phosphoenol pyruvate (PEP) in imitation of the synthetic principle used in nature. Thep resented biomimetic methodologies use enol formation for the highly efficient and flexiblef ormation of various C 6 -C 9 ulosonic acids.Particularly,efficient and concise syntheses of 3-deoxy-d-erythrohex-2-ulosonica cid (KDG,o verall5 0% yield), 3-deoxy-d-ribo-hept-2-ulosonic acid (DRH, overall 53% yield) and3 -deoxy-d-glycero-d-talo-non-2-ulosonic acid (4-epi-KDN,o verall 78% yield) are described. This direct efficienta pplication of pyruvic estersd oes not require additional demasking steps and thus surpassess previously methodologies utilising masked pyruvic synthons such 2-acetylthiazole and pyruvic aldehyde dimethyl acetal.

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