1246810-76-3Relevant academic research and scientific papers
Regio- and Stereoselective Syntheses of 7-Oxabicyclo[2.2.1]heptanes via a Gold(I)-Catalyzed Cycloisomerization of Alkynediols: Asymmetric Total Synthesis of Farnesiferol C
Gu, Yue-Qing,Zhang, Peng-Peng,Fu, Jun-Kai,Liu, Song,Lan, Yu,Gong, Jian-Xian,Yang, Zhen
, p. 1392 - 1397 (2016)
A highly regio- and stereoselective method to construct a broad range of 7-oxabicyclo[2.2.1]heptanes, which proceeds through a sequential reaction involving gold(I)-catalyzed cycloisomerization of alkynediols and sequential semi-pinacol-type 1,2-alkyl migration, was developed. The developed chemistry was applied to the asymmetric total synthesis of the natural product farnesiferol C.
Synthesis and Structure Revision of Dichrocephones A and B
Schmiedel, Volker M.,Hong, Young J.,Lentz, Dieter,Tantillo, Dean J.,Christmann, Mathias
, p. 2419 - 2422 (2018)
Herein, we report the first enantioselective synthesis of dichrocephones A and B, which are cytotoxic triquinane sesquiterpenes with a dense array of stereogenic centers within a strained polycyclic environment. Key features include the application of a catalytic asymmetric Wittig reaction, followed by stereoselective functionalization of the propellane core into a pentacyclic intermediate. Double reductive ring cleavage yielded the proposed structure of dichrocephone A. Mismatched spectroscopic data for our synthetic material compared to the natural isolate led us to revise the previously proposed configuration based on biosynthetic considerations and NMR calculations. Implementation of these findings culminated in the synthesis of dichrocephones A and B.
New transmetalation reagents for the gold-catalyzed visible light-enabled C(sp or sp2)-C(sp2) cross-coupling with aryldiazonium salts in the absence of a photosensitizer
Witzel, Sina,Sekine, Kohei,Rudolph, Matthias,Hashmi, A. Stephen K.
, p. 13802 - 13804 (2018)
The scope of photosensitizer-free visible light-driven gold-catalyzed cross-coupling was evaluated by a wide variety of organoboron and organosilicon species using four equivalents of aryldiazonium salts and (4-CF3-C6H4)3PAuCl in MeOH. In addition, a C(sp or sp2)-C(sp2) cross-coupling of organotrimethylsilanes and aryldiazonium salts was investigated. The reactions can be conducted under very mild reaction conditions, with a reduced amount of aryldiazonium salt (1.2 equiv.) by using a catalytic amount of Ph3PAuNTf2 in MeCN under irradiation with blue LEDs at room temperature.
Gold(I)-Catalyzed Cascade: Synthesis of 2,5-Disubstituted Pyrroles from N -Sulfonyl-2-(1-ethoxypropargyl)azetidines through Cyclization/Nucleophilic Substitution/Elimination
Pertschi, Romain,Miaskiewicz, Solène,Weibel, Jean-Marc,Pale, Patrick,Blanc, Aurélien
, p. 4151 - 4162 (2017)
N -Sulfonyl-2-(1-ethoxypropargyl)azetidine derivatives undergo a gold-catalyzed rearrangement in the presence of various alcohols furnishing the 2,5-disubstituted pyrroles in excellent yields (11 examples, 63-86%). Iodide or deuterium trappings of organogold intermediate as well as kinetic study confirmed the postulated cyclization/nucleophilic substitution/elimination mechanism..
Synthetic (N, N-Dimethyl)doxorubicin Glycosyl Diastereomers to Dissect Modes of Action of Anthracycline Anticancer Drugs
Wander, Dennis P. A.,Van Der Zanden, Sabina Y.,Vriends, Merijn B. L.,Van Veen, Branca C.,Vlaming, Joey G. C.,Bruyning, Thomas,Hansen, Thomas,Van Der Marel, Gijsbert A.,Overkleeft, Herman S.,Neefjes, Jacques J. C.,Codée, Jeroen D. C.
, p. 5757 - 5770 (2021)
Anthracyclines are effective drugs in the treatment of various cancers, but their use comes with severe side effects. The archetypal anthracycline drug, doxorubicin, displays two molecular modes of action: DNA double-strand break formation (through topoisomerase IIα poisoning) and chromatin damage (via eviction of histones). These biological activities can be modulated and toxic side effects can be reduced by separating these two modes of action through alteration of the aminoglycoside moiety of doxorubicin. We herein report on the design, synthesis, and evaluation of a coherent set of configurational doxorubicin analogues featuring all possible stereoisomers of the 1,2-amino-alcohol characteristic for the doxorubicin 3-amino-2,3-dideoxyfucoside, each in nonsubstituted and N,N-dimethylated forms. The set of doxorubicin analogues was synthesized using appropriately protected 2,3,6-dideoxy-3-amino glycosyl donors, equipped with an alkynylbenzoate anomeric leaving group, and the doxorubicin aglycon acceptor. The majority of these glycosylations proceeded in a highly stereoselective manner to provide the desired axial α-linkage. We show that both stereochemistry of the 3-amine carbon and N-substitution state are critical for anthracycline cytotoxicity and generally improve cellular uptake. N,N-Dimethylepirubicin is identified as the most potent anthracycline that does not induce DNA damage while remaining cytotoxic.
Construction of eight-membered carbocycles through gold catalysis with acetylene-tethered silyl enol ethers
Iwai, Tomohiro,Okochi, Hiori,Ito, Hideto,Sawamura, Masaya
, (2013)
Semihollow triethynylphosphanes were synthesized and employed as ligands in the gold-catalyzed 8-exo-dig cyclization of acetylene-tethered silyl enol ethers to obtain eight-membered-ring carbocycles (see scheme). The gold-phosphane catalysts promoted eith
Synthesis of Polysubstituted Fused Pyrroles by Gold-Catalyzed Cycloisomerization/1,2-Sulfonyl Migration of Yndiamides
Smith, Philip J.,Jiang, Yubo,Tong, Zixuan,Pickford, Helena D.,Christensen, Kirsten E.,Nugent, Jeremy,Anderson, Edward A.
supporting information, p. 6547 - 6552 (2021/08/30)
Yndiamides (bis-N-substituted alkynes) are valuable precursors to azacycles. Here we report a cycloisomerization/1,2-sulfonyl migration of alkynyl-yndiamides to form tetrahydropyrrolopyrroles, unprecedented heterocyclic scaffolds that are relevant to medicinal chemistry. This functional group tolerant transformation can be achieved using Au(I) catalysis that proceeds at ambient temperature, and a thermally promoted process. The utility of the products is demonstrated by a range of reactions to functionalize the fused pyrrole core.
Why can a gold salt react as a base?
Anania, Mariarosa,Ja?íková, Lucie,Ja?ík, Juraj,Roithová, Jana
supporting information, p. 7841 - 7852 (2017/10/06)
This study shows that gold salts [(L)AuX] (L = PMe3, PPh3, JohnPhos, IPr; X = SbF6, PF6, BF4, TfO, Tf2N) act as bases in aqueous solutions and can transform acetone to digold acetonyl complexes [(L)2Au2(CH2COCH3)]+ without any additional base present in solution. The key step is the formation of digold hydroxide complexes [(L)2Au2(OH)]+. The kinetics of the formation of the digold complexes and their mutual transformation is studied by electrospray ionization mass spectrometry and the delayed reactant labelling method. We show that the formation of digold hydroxide is the essential first step towards the formation of the digold acetonyl complex, the reaction is favoured by more polar solvents, and the effect of counter ions is negligible. DFT calculations suggest that digold hydroxide and digold acetonyl complexes can exist in solution only due to the stabilization by the interaction with two gold atoms. The reaction between the digold hydroxide and acetone proceeds towards the dimer {[(L)Au(OH)]·[(L)Au(CH3COCH3)]+}. The monomeric units interact at the gold atoms in the perpendicular arrangement typical of the gold clusters bound by the aurophilic interaction. The hydrogen is transferred within the dimer and the reaction continues towards the digold acetonyl complex and water.
Photosensitizer-Free, Gold-Catalyzed C–C Cross-Coupling of Boronic Acids and Diazonium Salts Enabled by Visible Light
Witzel, Sina,Xie, Jin,Rudolph, Matthias,Hashmi, A. Stephen K.
supporting information, p. 1522 - 1528 (2017/05/05)
The first photosensitizer-free visible light-driven, gold-catalyzed C–C cross-couplings of arylboronic acids and aryldiazonium salts are reported. The reactions can be conducted under very mild conditions, using a catalytic amount of tris(4-trifluoromethyl)phosphinegold(I) chloride [(4-CF3-C6H4)3PAuCl] with methanol as the solvent allowing an alternative access to a variety of substituted biaryls in moderate to excellent yields with broad functional group tolerance. (Figure presented.).
Gold(I)-catalyzed synthesis of dihydrodibenzoquinolizinium salts
Marien, Niels,Verniest, Guido
supporting information, p. 1996 - 2000 (2017/06/09)
A gold-catalyzed cyclization of 1-alkynyl-2-aryl tetrahydroisoquinolines is described for the synthesis of novel dihydrodibenzoquinolizinium salts. The reaction mechanism is likely to involve a 6-endo-dig cyclization and subsequent oxidation by air to give a relatively stable arylgold intermediate. This gold species undergoes protodeauration under acidic conditions to afford the title compounds. An NMR study was performed to gain further evidence and insight on the presence of the arylgold intermediate and the reaction mechanism. (Figure presented.).
