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Приказ резултата 2061-2069 од 2069
Synthesis of endoperoxides by domino reactions of ketones and molecular oxygen
(Royal Soc Chemistry, Cambridge, 2015)
Domino reactions of ketones with molecular oxygen in the presence of potassium hydroxide and potassium t-butoxide afford cyclic hydroperoxy acetals (3,5-dihydroxy-1,2-dioxanes). Mixed endoperoxides can also be obtained in ...
Cyclization Reactions of Oxyallyl Cation. A Method for Cyclopentane Ring Formation
(American Chemical Society (ACS), 2019)
Unsaturated oxyallyl cations with a suitably positioned alkene bond undergo 5-exo-cyclization with the formation of vinylcyclopentane derivatives. Alkyne analogues provide allenes. The reaction proceeds with a moderate to ...
Synthesis of vinyldihydropyran by cooperative catalysis
(Serbian Chemical Soc, Belgrade, 2016)
Delta(5)-Unsaturated aldehydes with a suitably positioned allylic halide, or phosphate, leaving group undergo doubly-catalyzed cyclization to give dihydropyran derivatives. The cyclization proceeds under the synergetic ...
Gold(I)-Catalyzed Domino Cyclizations of Diynes for the Synthesis of Functionalized Cyclohexenone Derivatives. Total Synthesis of (-)-Gabosine H and (-)-6-epi-Gabosine H
(American Chemical Society (ACS), 2016)
1,6-Diynes with a t-butylcarbonate group in the propargylic position undergo gold(I)-catalyzed dominocyclization which affords alpha-hydroxycyclohexenones. The described sequence can be applied on functionalized, highly ...
Substrate Stereocontrol in the Intramolecular Organocatalyzed Tsuji-Trost Reaction: Enantioselective Synthesis of Allokainates
(American Chemical Society (ACS), 2014)
Organocatalyzed Tsuji-Trost cyclization of 3b proceeds with asymmetric induction and allows for stereoselective synthesis of (+)-allokainic acid. The stereochemical outcome of the cyclization was predicted by calculations.
Total synthesis and biological evaluation of atrop-O-benzyl-desmethylabyssomicin C
(Royal Soc Chemistry, Cambridge, 2014)
The total synthesis of desmethylabyssomicin C analogue 1 was accomplished using diastereotopos-selective ring closing metathesis and Nozaki-Hiyama-Kishi cyclization as the key steps. The synthetic analogue retained its ...
Total synthesis and biological evaluation of (-)-atrop-abyssomicin C
(Royal Soc Chemistry, Cambridge, 2013)
Enantioselective synthesis of a marine antibiotic (-)-atrop-abyssomicin C was accomplished in 21 steps, in 1.8% overall yield (4%, based on the recovered starting material). The key steps of the synthesis are the formation ...
Synthetic studies towards D-modified paclitaxel analogues / Sintetičke studije analoga paklitaksela sa modifikovanim D-prstenom
(Serbian Chemical Soc, Belgrade, 2012)
A synthetic sequence has been developed for the preparation of 9,10- di-O-diacetyl-4-desmethylene-4β-(3-butenyl)-4α-hydroxy-5-O-mesyltaxicin I- -1,2-carbonate 3, an intermediate in an attempted synthesis of a cyclobutane ...
Double Asymmetric Induction in Organocatalyzed Aldol Reactions: Total Synthesis of (+)-2-epi-Hyacinthacine A(2) and (-)-3-epi-Hyacinthacine A(1)
(Wiley-V C H Verlag Gmbh, Weinheim, 2013)
The stereodivergent synthesis of two hyacinthacine analogues, which relies on an organocatalyzed aldol addition, is described. The aldol addition of dioxanone to an -N-carbobenzyloxy-substituted chiral aldehyde, promoted ...