Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Seit Februar 2021 bietet Wolfgang Brandt, ehemaliger Leiter der Arbeitsgruppe Computerchemie am IPB, sein Citizen Science-Projekt zur Pilzbestimmung an. Dafür hat er in regelmäßigen Abständen öffentliche Vorträge zur Vielfalt…
Zanatta, N.; Mittersteiner, M.; Aquino, E. C.; Budragchaa, T.; Wessjohann, L. A.; Bonacorso, H. G.; Martins, M. A. P.;Synthesis of methylene-bridged trifluoromethyl azoles using 5-(1,2,3-Triazol-1-yl)enonesSynthesis54439-450(2022)DOI: 10.1055/s-0040-1719837
A protocol for synthesizing triazole-containing pyrazolines and pyrazoles selectively using trifluoromethylated 5-(1,2,3-triazol-1-yl)enones as starting materials, is reported. The selectivity of the reaction was controlled by the nature of the hydrazine or derivative used: free hydrazines furnished the 1,5-regiosiomer exclusively in yields up to 98%, whereas protected hydrazines provided the 1,3-regioisomer in yields up to 77%. To demonstrate the synthetic versatility of the triazole-based enone, reactions with other unsymmetrical dinucleophiles (hydroxylamine hydrochloride and S-methyl isothiourea sulfates) allowed the selective preparation of triazole-containing isoxazoline and pyrimidine rings.
Publikation
Wouters, A. D.; Bessa, A. B.; Sachini, M.; Wessjohann, L. A.; Lüdtke, D. S.;Boron-Zinc Exchange in The Diastereoselective Arylation of Sugar-Based Aldehydes: Stereoselective Synthesis of (+)-7-epi-Goniofufurone and AnaloguesSynthesis452222-2233(2013)DOI: 10.1055/s-0033-1339285
The substrate-controlled diastereoselective arylation of chiral aldehydes readily available from carbohydrates is described, using the boron–zinc exchange reaction to generate the transferable aryl groups. The methodology developed was applied to the total synthesis of the styryllactone (+)-7-epi-goniofufurone and analogues thereof.
Publikation
Gulyas-Fekete, G.; Boluda, C. J.; Westermann, B.; Wessjohann, L. A.;Anti-Friedel-Crafts-Type Substitution To Form Biaryl LinkagesSynthesis453038-3043(2013)DOI: 10.1055/s-0033-1339682
The ipso-substitution of one (or two) hydroxy groups of phloroglucinol with arene nucleophiles (e.g., o-xylene, tetralin, biphenyl) can be achieved easily under Friedel–Crafts-type conditions with or without the use of organic solvents affording a variety of 3,5-dihydroxybiphenyls (57–89% yields). The new method has significant practical advantages compared to classical biaryl-coupling routes.
Publikation
Henze, M.; Kreye, O.; Brauch, S.; Nitsche, C.; Naumann, K.; Wessjohann, L. A.; Westermann, B.;Photoaffinity-Labeled Peptoids and Depsipeptides by Multicomponent ReactionsSynthesis20102997-3003(2010)DOI: 10.1055/s-0030-1258182
Photoaffinity tags can be incorporated easily into peptoids and congeners by the Ugi and Passerini multicomponent reactions. Products related to photo-methionine and photo-leucine can be accomplished by diazirine-containing building blocks. The same protocols can be used to synthesize derivatives with benzophenone photo cross-linkers.