78132-75-9Relevant academic research and scientific papers
One and Two-Carbon Homologation of Primary and Secondary Alcohols to Corresponding Carboxylic Esters Using β-Carbonyl BT Sulfones as a Common Intermediate
Bon, David J.-Y. D.,Ková?, Ond?ej,Ferugová, Vendula,Zále?ák, Franti?ek,Pospí?il, Ji?í
, p. 4990 - 5001 (2018/05/17)
Herein we report the efficient one- and two-carbon homologation of 1° and 2° alcohols to their corresponding homologated esters via the Mitsunobu reaction using β-carbonyl benzothiazole (BT) sulfone intermediates. The one-carbon homologation approach uses standard Mitsunobu C-S bond formation, oxidation and subsequent alkylation, while the two-carbon homologation uses a less common C-C bond forming Mitsunobu reaction. In this latter case, the use of β-BT sulfone bearing esters lowers the pKa sufficiently enough for the substrate to be used as a carbon-based nucleophile and deliver the homologated β-BT sulfone ester, and this superfluous sulfone group can then be cleaved. In this paper we describe several methods for the effective desulfonylation of BT sulfones and have developed methodology for one-pot alkylation-desulfonylation sequences. As such, overall, a one-carbon homologation sequence can be achieved in a two-pot (four step) procedure and the two-carbon homologation in a two-pot (three step) procedure (three-pot; four step when C-acid synthesis is included). This methodology has been applied to a wide variety of functionality (esters, silyl ethers, benzyls, heteroaryls, ketones, olefins and alkynes) and are all tolerated well providing good to very good overall yields. The power of our method was demonstrated in site-selective ingenol C20 allylic alcohol two-carbon homologation.
Discovery and SAR study of hydroxyacetophenone derivatives as potent, non-steroidal farnesoid X receptor (FXR) antagonists
Liu, Peng,Xu, Xing,Chen, Lili,Ma, Lei,Shen, Xu,Hu, Lihong
, p. 1596 - 1607 (2014/03/21)
Compound 1 (IC50 = 35.2 ± 7.2 μM), a moderate FXR antagonist was discovered via high-throughput screening. Structure-activity relationship studies indicated that the shape and the lipophilicity of the substituents of the aromatic ring affect the activity dramatically, increasing the shape and the lipophilicity of the substituents of the aromatic ring enhances the potency of FXR antagonists. Especially, when the OH at C2 position of the aromatic ring was replaced by the OBn substituent (analog 2b), its activity could be improved to IC50 = 1.1 ± 0.1 μM. Besides, the length of the linker and the tetrazole structure are essential for retaining the activity.
Selective hydrogenolysis of benzyl ethers in the presence of benzylidene acetals with Raney nickel
Vincent, Aurélie,Prunet, Jo?lle
, p. 4075 - 4077 (2007/10/03)
A simple method to remove selectively a benzyl group protecting a hydroxyl function in the presence of a benzylidene acetal by catalytic hydrogenolysis with Raney nickel is reported. This method was successfully applied to the synthesis of the C1-C14 fragment of dolabelides.
Syntheses of model compounds related to an antigenic epitope in pectic polysaccharides from Bupleurum falcatum L.
Hada, Noriyasu,Ogino, Tomoko,Yamada, Haruki,Takeda, Tadahiro
, p. 7 - 17 (2007/10/03)
Stereocontrolled syntheses of model compounds related to a category of the major antigenic epitope against anti-bupleurum 2IIc/PG-1-IgG from an anti-ulcer pectic polysaccharide are described. Glycosylation of the glucuronic acid donors methyl(2,3-di-O-ben
Intramolecular photocyclisation reactions of 5-tert-butyldimethylsilyloxymethyl-3-(3-formylpropyl)furan-2(5H)-one: Formation of bicyclic and spirobicyclic lactones
Brown, David,Drew, Michael G. B.,Mann, John
, p. 3651 - 3655 (2007/10/03)
5-tert-Butyldimethylsilyloxymethyl-3-(3-formylpropyl)furan-2(5H)-one has been synthesised and upon irradiation yields either one homochiral bicyclic lactone or a mixture of spirobicyclic lactones (in modest yield) depending upon the irradiation conditions.
Manganese(III)-based oxidative freeradical reaction of α-allyl-β-keto ester with molecular oxygen
Ohshima, Takashi,Sodeoka, Mikiko,Shibasaki, Masakatsu
, p. 8509 - 8512 (2007/10/02)
Oxidative reactions of α-allyl-β-keto esters 5 with Mn(OAc)3·2H2O give the δ-hydroxy-β-,γ-unsaturated-α-keto esters 6 in good yields. The mechanism of this reaction is discussed.
TRIPHENYLCARBENIUM AND TRIS(P-BROMOPHENYL)AMMONIUMYL ION INDUCED LACTONIZATIONS OF ω-BENZYLOXY AND ω-P-METHOXYBENZYLOXY METHYL ESTERS
Hoye, Thomas R.,Kurth, Mark J.,Lo, Vincent
, p. 815 - 818 (2007/10/02)
The title reaction leads to smooth generation of five and six membered lactones via direct nucleophilic participation of the carbomethoxy group in intermediates of type 3.
