Synthesis and determination of the absolute configuration of fugomycin and desoxyfugomycin: CD spectroscopy and fungicidal activity of butenolides.

  title={Synthesis and determination of the absolute configuration of fugomycin and desoxyfugomycin: CD spectroscopy and fungicidal activity of butenolides.},
  author={Manfred Braun and Andreas Hohmann and Jaykumar Rahematpura and Corinna B{\"u}hne and Stefan Grimme},
  volume={10 18},
The dibromoalkenes (S)-3 and (R)- and (S)-4 are intermediates in the syntheses of the naturally occurring fungicidal butenolides fugomycin (1) and desoxyfugomycin (2), respectively. The stereoselective bromine-lithium exchange that leads to the carbenoid 12 and the vinyllithium reagent 17 a on the one hand, and palladium-catalyzed coupling reactions of the dibromoalkene 3 and the bromolactone 22 on the other are key steps en route to the butenolides 1 and 2. The chiral building blocks (S)-3, (R… 
2-(p-Tolylsulfinyl)benzyl halides as efficient precursors of optically pure trans-2,3-disubstituted aziridines.
Experimental results suggest substituted 2-p-tolylsulfinyl benzylcarbanions evolve through benzyl halocarbenoids as intermediates, whereas theoretical calculations support the formation of benzyl carbanions.
A Comparative Mechanistic and Kinetic Study of the Synthesis Reaction of 3, 4, 5‐Substituted Furan‐2(5H)‐ones: Solvent Effect
Solvent can influence kinetics and mechanism of a chemical reaction. Herein, the different behavior of solvent media on the competitive mechanism between benzaldehyde (1), 4-ethylaniline (2) and
Anti-inflammatory and α-Glucosidase Inhibitory Activities of Labdane and Norlabdane Diterpenoids from the Rhizomes of Amomum villosum.
A new tetranorditerpenoid (1), two new labdane diterpenoids (2, 3), and nine known analogues (4-12) were isolated from the rhizomes of Amomum villosum var. xanthioides. Compound 1 is an unprecedented
Gold(III) chloride catalyzed synthesis of chiral substituted 3-formyl furans from carbohydrates: application in the synthesis of 1,5-dicarbonyl derivatives and furo[3,2-c]pyridine.
To demonstrate the potentiality of chiral 3-formyl furan derivatives, a TiBr4 -catalyzed reaction of these derivatives has been shown to offer efficient access to 1,5-dicarbonyl compounds, which on treatment with NH4 OAc in slightly acidic conditions afforded substituted furo[3,2-c]pyridine.
Chiral aromatase and dual aromatase-steroid sulfatase inhibitors from the letrozole template: synthesis, absolute configuration, and in vitro activity.
The results suggest that a new structural class of DASI for potential treatment of hormone-dependent breast cancer has been identified, and this is the first report of STS inhibition by an enantiopure nonsteroidal compound.
Effect of different substituents on the one-pot formation of 3,4,5-substituted furan-2(5H)-ones: a kinetics and mechanism study
The kinetics of reactions between benzaldehyde and diethyl acetylenedicarboxylate with para-substituted anilines for the one-pot formation of 3,4,5-substituted furan-2(5H)-ones have been studied
Enantioselective syntheses and configuration assignments of gamma-chiral butenolides from Plagiomnium undulatum: butenolide synthesis from tetronic acids.
Both enantiomers of the gamma-chiral alpha,beta-dimethylated butyrolactones nat-1 and nat-2 from the moss Plagiomnium undulatum were synthesized stereoselectively through butenolides and tetronic
Tellurium-promoted stereoselective hydrodebromination of 1,1-dibromoalkenes: synthesis of (E)-bromoalkenes
We describe herein an efficient and simple method for the stereoselective hydrodebromination of 1,1-dibromoalkenes by using a catalytic amount of the nucleophilic species of tellurium, generated in
Galiellalactone analogs and their possible precursors from Sarcosomataceae.


Stereoselective Synthesis of Highly Functionalized Cyclopropanes. Application to the Asymmetric Synthesis of (1S,2S)-2,3-Methanoamino Acids.
Molecular mechanics calculations using a modified MM2 type force field adapted to the pi-allyl palladium complexes have explained the reversibility of the palladium-catalyzed cyclization step, responsible for the low enantioselectivity observed and for the formation of byproducts, i.e., azepine derivatives 8a,b arising from subsequent aza Cope ring expansion.
Synthesis of Enantiomeric N -(2-Phosphonomethoxypropyl) Derivatives of Purine and Pyrimidine Bases. II. The Synthon Approach
Another approach to ( R )- and ( S )- N -(2-phosphonomethoxypropyl) derivatives of purine and pyrimidine bases (PMP derivatives) I and II is described, consisting in alkylation of the heterocyclic
The Stille Reaction of 1,1-Dibromo-1-alkenes: Preparation of Trisubstituted Alkenes and Internal Alkynes.
  • W. Shen, Le Wang
  • Chemistry, Biology
    The Journal of organic chemistry
  • 1999
This new method for internal alkyne preparation is general, requires very mild reaction conditions, and gives high yields.
Stereoselective Hydrogenolysis of 1,1-Dibromo-1-alkenes and Stereospecific Synthesis of Conjugated (Z)-Alkenyl Compounds
The Pd-catalyzed hydrogenolysis of 1,1-dibromoalkenes with Bu3SnH occurs at room temperature stereoselectively to give (Z)-1-bromo-1-alkenes. We sought to determine the optimal reaction conditions
Palladium-Catalyzed Cyclocarbonylation of Terminal and Internal Alkynols to 2(5H)-Furanones
A series of substituted alkynols, containing alkyl, phenyl, and vinyl groups at the acetylenic terminal, were found to undergo direct carbonylation to the corresponding substituted 2(5H)-furanones in
Chiral vinyl anions for «carbonyl umpolung». Highly stereoselective addition of a novel enantiomerically pure vinyllithium reagent to aldehydes
The vinyllithium reagent 13 and its enantiomer are generated by a bromine/lithium exchange reaction starting from dibromoalkenes 11 and 12, both available from the corresponding enantiomer of alkyl
Stereoselective radical additions of γ-oxy-α,β-unsaturated ester derivatives; 1,2-asymmetric induction in acyclic and cyclisation systems
Examination was made of 1,2-asymmetric induction in the addition of alkyl radicals to γ-oxy-α,β-unsaturated ester derivatives 1 and 2 prepared from ethyl lactate and