Bognár Rezső szerves kémikus egyetemi tanár, akadémikus, tudománypolitikus (1913-1990)

rezső bognár, Professor of organic cheMistry, MeMber of the hungarian acadeMy of arts and sciences, scientific adviser. Rezső Bognár was one of the most outstanding students of Géza Zemplén, the irst great educator of organic chemistry in Hungary. When the School of Sciences was established in 1949 at the University of Debrecen, Professor Bognár was appointed head of the Department of Organic Chemistry. As a result of this decision, he became the founding father of organic chemistry work in Debrecen. Hewas soon elected member of the Hungarian Academy of Arts and Sciences and he served for two terms as Rector of Lajos Kossuth University of Arts and Sciences. Professor Bognár was founding president of the Debrecen Academic Committee, which position he held until his death. It was as the result of his nationally recognized public activity that the headquarters in Debrecen of DAB (=the Debrecen Academic Committee) and the Chemistry Building on the Debrecen campus were erected. He also organized the Antibio tic Chemical Research Group of the Hungarian Academy. he researchers of the Bognár school have brought out over 400 scientiic publications and submitted a large number of patents pertaining to the themes of the chemistry of carbohydrates, antibiotics, alkaloids, and lavonoids.His activities in the Hungarian National Assembly and the Hungarian Academy of Arts and Sciences have greatly contributed to the numerous successes of our university

Photoinitiated Thiol-Ene Reactions of Various 2,3-Unsaturated O-,C- S- and N-Glycosides – Scope and Limitations Study

The photoinitiated thiol-ene addition reaction is a highly stereo- and regioselective, and environmentally friendly reaction proceeding under mild conditions, hence it is ideally suited for the synthesis of carbohydrate mimetics. A comprehensive study on UV-light-induced reactions of 2,3- unsaturated O-, C-, S- and N-glycosides with various thiols was performed. The effect of experimental parameters and structural variations of the alkenes and thiols on the efficacy and regio- and stereoselectivity of the reactions was systematically studied and optimized. The type of anomeric heteroatom was found to profoundly affect the reactivity of 2,3-unsaturated sugars in the thiol-ene couplings. Hydrothiolation of 2,3-dideoxy O-glycosyl enosides efficiently produced the axially C2-S-substituted addition products with high to complete regioselectivity. Moderate efficacy and varying regio- and stereoselectivity were observed with 2,3- unsaturated N-glycosides and no addition occurred onto the endocyclic double bond of C-glycosides. Upon hydrothiolation of 2,3-unsaturated S-glycosides, the addition of thiyl radicals was followed by elimination of the thiyl aglycone resulting in 3-S-substituted glycals

New semisynthetic teicoplanin derivatives have comparable in vitro activity to that of oritavancin against clinical isolates of VRE

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A low-temperature, photoinduced thiol-ene click reaction: a mild and efficient method for the synthesis of sugar-modified nucleosides

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Photoinitiated Thiol-Ene Reactions of Various 2,3-Unsaturated O-, C- S- and N-Glycosides: scope and Limitations Study

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A synthetic and in silico study on the highly regioselective Diels-Alder reaction of the polyenic antifungal antibiotics natamycin and flavofungin

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Új antibiotikum-származékok szintézise = Synthesis of new antibiotic derivatives

A leinamicin nevű, DNS-hasító daganatellenes antibiotikum hatásáért felelős molekularészletét szintetikusan beültettük nukleozidokba, s így a daunomicin biológai aktivitásához hasonló értékű citotoxikus származékokat nyertünk. Acetilénkötést tartalmazó leinamicinanalógunk szintén hatásosnak bizonyult, s hozzájárult az antibiotikum hatásmechanizmusának felderítéséhez. Megvalósítottuk antibakteriális, a vankomicin-családhoz tartozó glikopeptid-antibiotikumok és daganatellenes antraciklin-antibiotikumok négyögsavdiamid molekularészlet segítségével kialakított konjugátumainak, illetve dimerjeinek szintézisét, s több esetben igen kedvező biológiai hatású származékokat kaptunk. Tanulmányoztuk szénhidrátok, antibiotikumok, nukleozidok telekelikus dimerjeinek biológiai hatását, illetve különleges aggregációs tulajdonságukat,. Metilgallátból kiindulva oxidatív dezaromatizációval, s cikloaddíciós reakciót felhasználva a perikozin nevű, citotoxikus antibiotikum áthidalt gyűrűs analógját szintetizáltuk. | The active structural portion of the DNA-cleaving anticancer antibiotic leinamycin was synthetically built into nucleosides. In this way new leinamycin analogs were obtained with citotoxicity comparable to that of daunomycin. A new type of leinamycin analog containing carbon-carbon triple bond was synthesized and it gave an important information for elucidation of mechanism of action of leinamycin. Using the squaric amide linker new conjugates and dimers of antibacterial glycopeptide antibiotics of the vancomycin group and of anticancer anthracyclines have been synthesized. Some of the conjugates possess very promising biological activity. The aggregation properties and antibacterial activity of telechelic dimers of antibiotics, carbohydrates and nucleosides have been studied. Bicyclic analogs of the cytotoxic antibiotic pericosin was synthesized from methyl gallate