A new enantioselective total synthesis of pachastrissamine (jaspine B) was achieved from a known alpha,beta-unsaturated aldehyde by utilizing Córdova's asymmetric epoxidation as the chirality-inducing step. The 2,3-cis stereochemistry of pachastrissamine was established via intramolecular epoxide ring opening of a gamma,delta-epoxy-alpha,beta-unsaturated ester intermediate coupled with oxy-Mich...

We describe here a Tf₂NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic ...

A one-pot, two step synthesis of highly substituted imidazoles has been carried out in good to excellent yields for the first time via a cascade intermolecular aza-SN2'-intramolecular aza-Michael addition involving a variety of Morita-Baylis-Hillman acetates of nitroalkenes and amidines in the presence of DABCO at room temperature. The synthetic and biological utility of the products has been d...

The asymmetric synthesis of the orthogonally funtionalised compounds tert-butyl 2-N-benzyl-N-alpha-methylbenzylamino-5-methoxycarbonylmethylcyclopentane- 1-carboxylate and methyl 2-N-benzyl-N-alpha-methylbenzylamino-5-carboxymethylcyclo- pentane-1-carboxylate by a domino reaction of tert-butyl methyl (E,E)-octa-2,6- diendioate with lithium N-alpha-methylbenzyl-N-benzylamide initiated by a Micha...

Kinesin, dynein, and some myosin motor proteins transport cargoes within the cell by “walking” along polymeric filaments, that is carrying out successive, repetitive, mostly directional changes of their point of contact with the molecular track without completely detaching from it. These extraordinary biomolecules are inspiring scientists to mimic aspects of their dynamics to create artificial ...

Here we describe a direct access to 2,2,3-trisubstituted syn γ-nitroaldehydes by addition of α-branched aryl acetaldehydes nitroolefins promoted cinchona based squaric acid-derived amino acid peptide. Different α-methyl arylacetaldehydes react with β-aromatic and β-alkyl afford the Michael adducts in high enantioselectivity syn-selectivity. NMR experiments DFT calculations predict reaction occu...

A but-3-yn-2-one-based 7-diethylaminocoumarin dye was exploited as a fluorescent probe to specifically detect Cys over Hcy/GSH in pure PBS buffer. The probe itself is nonfluorescent due to the donor-excited photoinduced electron transfer (d-PET) process. The Cys-induced Michael addition-rearrangement cascade reaction leads to an amino-substituted product with strong fluorescence due to inhibiti...

Four novel paulomycin derivatives have been isolated from S. albus J1074 grown in MFE culture medium. These compounds are structural analogs of antibiotics 273a2α and 273a2β containing a thiazole moiety, probably originated through an intramolecular Michael addition. The novel, thiazole, moiety-containing paulomycins show a lower antibiotic activity than paulomycins A and B against Gram-positiv...

Pyrazolines, which are nitrogen including five-membered heterocyclic structures, have been used in the organic and pharmaceutical industries. This study aimed was to synthesize characterizes new series of 3,5-diphenyl-4,5-dihydro-1H-pyrazole derivatives. The pyrazoline compounds synthesized from chalcones hydrazine hydrate two steps. In first step, were 2-amino acetophenone various substituted ...