- Enantioselective synthesis of 3-substituted 1,2-oxazinanes via organocatalytic intramolecular aza-Michael addition
-
A highly enantioselective intramolecular 6-exo-trig aza-Michael addition was developed to afford chiral 3-substituted 1,2-oxazinanes in high yields (up to 99% yield) and good enantioselectivities (up to 98/2 er). These reactions were enabled by a quinine-derived primary-tertiary diamine as a catalyst and pentafluoropropionic acid (PFP) as a co-catalyst.
- Cheng, Shuanghua,Yu, Shouyun
-
-
Read Online
- Study of Intermediates in Iridium-(Phosphoramidite,Olefin)-Catalyzed Enantioselective Allylic Substitution
-
Experimental mechanistic studies of iridium-catalyzed, enantioselective allylic substitution enabled by (phosphoramidite,olefin) ligands are reported. (η2-Allylic alcohol)iridium(I) and (η3-allyl)iridium(III) complexes were synthesiz
- R?ssler, Simon L.,Krautwald, Simon,Carreira, Erick M.
-
-
Read Online
- Sequential deoxyfluorination approach for the synthesis of protected α,β,γ-trifluoro-δ-amino acids
-
Backbone-homologated amino acids have been synthesized, containing three vicinal fluorine atoms placed stereospecifically along the carbon chain. Different trifluoro stereoisomers are found to have contrasting conformations, consistent with known stereoel
- Cheerlavancha, Raju,Lawer, Aggie,Cagnes, Marina,Bhadbhade, Mohan,Hunter, Luke
-
-
Read Online
- Synthesis of 2-(3-Arylallylidene)-3-oxindoles via Dirhodium(II)-Catalyzed Reaction of 3-Diazoindolin-2-imines with 1-Aryl-Substituted Allylic Alcohols and Computational Insights
-
A straightforward approach for the synthesis of 2-(3-arylallylidene)-3-oxindoles has been achieved by the dirhodium(II)-catalyzed reaction of 3-diazoindolin-2-imines with 1-aryl-substituted allylic alcohols. This protocol employs easily accessible feedsto
- Gao, Ke,Kou, Luyao,Fu, Rui,Bao, Xiaoguang
-
-
Read Online
- The Pharmacological Heterogeneity of Nepenthone Analogs in Conferring Highly Selective and Potent κ-Opioid Agonistic Activities
-
To develop novel analgesics with no side effects or less side effects than traditional opioids is highly demanded to treat opioid receptor mediated pain and addiction issues. Recently, κ-opioid receptor (KOR) has been established as an attractive target,
- Li, Wei,Long, Jian-Dong,Qian, Yuan-Yuan,Long, Yu,Xu, Xue-Jun,Wang, Yu-Jun,Shen, Qing,Wang, Zuo-Neng,Yang, Xi-Cheng,Xiao, Li,Sun, Hong-Peng,Xu, Yu-Long,Chen, Yi-Yi,Xie, Qiong,Wang, Yong-Hui,Shao, Li-Ming,Liu, Jing-Gen,Qiu, Zhui-Bai,Fu, Wei
-
-
Read Online
- Synthesis of C5-allylindoles through an iridium-catalyzed asymmetric allylic substitution/oxidation reaction sequence of N-alkyl indolines
-
Iridium/Br?nsted acid cooperative catalyzed asymmetric allylic substitution reactions at the C5 position of indolines have been reported for the first time. The highly efficient protocol allows rapid access to various C5-allylated products in good to high
- Lu, Jiamin,Xu, Ruigang,Zeng, Haixia,Zhong, Guofu,Wang, Meifang,Ni, Zhigang,Zeng, Xiaofei
-
supporting information
p. 3426 - 3431
(2021/05/07)
-
- Mild Darzens Annulations for the Assembly of Trifluoromethylthiolated (SCF3) Aziridine and Cyclopropane Structures
-
We report mild new annulation approaches to trisubstituted trifluoromethylthiolated (SCF3) aziridines and cyclopropanes via Darzens inspired protocols. The products of these anionic annulations, rarely studied previously, possess attractive features rendering them valuable building blocks for synthesis platforms. In this study, trisubstituted acetophenone nucleophiles bearing SCF3 and bromine substituents in their α position were shown to undergo [2 + 1] annulations with vinyl ketones and tosyl-protected imines under mild reaction conditions.
- Delost, Michael D.,Njardarson, Jon T.
-
supporting information
p. 6121 - 6125
(2021/08/16)
-
- Size-Exclusion Borane-Catalyzed Domino 1,3-Allylic/Reductive Ireland–Claisen Rearrangements: Impact of the Electronic and Structural Parameters on the 1,3-Allylic Shift Aptitude
-
The reductive Ireland–Claisen rearrangement through borane-mediated hydrosilylation is reported. The method employs a borane catalyst with a special structural design and affords access to synthetically relevant products with high diastereoselectivity. Depending on electronic and structural parameters, the reaction can be coupled with a 1,3-allylic shift, thus the valence isomer of the Ireland–Claisen product is formed.
- Fegyverneki, Dániel,Kolozsvári, Natália,Molnár, Dániel,Egyed, Orsolya,Holczbauer, Tamás,Soós, Tibor
-
supporting information
p. 2179 - 2183
(2019/01/04)
-
- Manganese-Catalyzed Ring-Opening Coupling Reactions of Cyclopropanols with Enones
-
A manganese-catalyzed ring-opening coupling reaction of cyclopropanols with enones for the facile and efficient preparation of 1,6-diketones is described. A wide array of synthetically important 1,6-diketones bearing manifold functional groups are obtained with up to 93% yield. These reactions feature broad substrate scopes, environmentally benign conditions, inexpensive catalyst, and operational simplicity.
- Zhang, Yong-Hui,Zhang, Wen-Wei,Zhang, Ze-Yu,Zhao, Kai,Loh, Teck-Peng
-
supporting information
p. 5101 - 5105
(2019/07/03)
-
- Structural Modification of Natural Product Ganomycin i Leading to Discovery of a α-Glucosidase and HMG-CoA Reductase Dual Inhibitor Improving Obesity and Metabolic Dysfunction in Vivo
-
It is a great challenge to develop drugs for treatment of metabolic syndrome. With ganomycin I as a leading compound, 14 meroterpene derivatives were synthesized and screened for their α-glucosidase and HMG-CoA reductase inhibitory activities. As a result, a α-glucosidase and HMG-CoA reductase dual inhibitor ((R,E)-5-(4-(tert-butyl)phenyl)-3-(4,8-dimethylnona-3,7-dien-1-yl)furan-2(5H)-one, 7d) with improved chemical stability and long-term safety was obtained. Compound 7d showed multiple and strong in vivo efficacies in reducing weight gain, lowering HbAlc level, and improving insulin resistance and lipid dysfunction in both ob/ob and diet-induced obesity (DIO) mice models. Compound 7d was also found to reduce hepatic steatosis in ob/ob model. 16S rRNA gene sequencing, SCFA, and intestinal mucosal barrier function analysis indicated that gut microbiota plays a central and causative role in mediating the multiple efficacies of 7d. Our results demonstrate that 7d is a promising drug candidate for metabolic syndrome.
- Wang, Kai,Bao, Li,Zhou, Nan,Zhang, Jinjin,Liao, Mingfang,Zheng, Zhongyong,Wang, Yujing,Liu, Chang,Wang, Jun,Wang, Lifeng,Wang, Wenzhao,Liu, Shuangjiang,Liu, Hongwei
-
p. 3609 - 3625
(2018/05/01)
-
- 1,3-Dioxa-[3,3]-sigmatropic Oxo-Rearrangement of Substituted Allylic Carbamates: Scope and Mechanistic Studies
-
An unexpected 1,3-dioxa-[3,3]-sigmatropic rearrangement during the treatment of aryl- and alkenyl-substituted allylic alcohols with activated isocyanates is reported. The reorganization of bonds is highly dependent on the electron density of the aromatic
- Agirre, Maddalen,Henrion, Sylvain,Rivilla, Ivan,Miranda, José I.,Cossío, Fernando P.,Carboni, Bertrand,Villalgordo, José M.,Carreaux, Fran?ois
-
p. 14861 - 14881
(2019/01/04)
-
- Carbene-Catalyzed Reductive Coupling of Nitrobenzyl Bromide and Nitroalkene via the Single-Electron-Transfer (SET) Process and Formal 1,4-Addition
-
A carbene-catalyzed reductive 1,4-addition of nitrobenzyl bromides to nitroalkenes is disclosed. The reaction proceeds via a carbene-enabled single-electron-transfer process that generates radicals as key intermediates. The present study expands the potentials of carbene catalysis and offers unusual transformations for common substrates in organic synthesis.
- Wang, Yuhuang,Du, Yu,Huang, Xuan,Wu, Xingxing,Zhang, Yuexia,Yang, Song,Chi, Yonggui Robin
-
supporting information
p. 632 - 635
(2017/02/10)
-
- Rhodium-Catalyzed Asymmetric N?H Functionalization of Quinazolinones with Allenes and Allylic Carbonates: The First Enantioselective Formal Total Synthesis of (?)-Chaetominine
-
An unprecedented asymmetric N?H functionalization of quinazolinones with allenes and allylic carbonates was successfully achieved by rhodium catalysis with the assistance of chiral bidentate diphosphine ligands. The high efficiency and practicality of this method was demonstrated by a low catalyst loading of 1 mol % as well as excellent chemo-, regio-, and enantioselectivities with broad functional group compatibility. Furthermore, this newly developed strategy was applied as key step in the first enantioselective formal total synthesis of (?)-chaetominine.
- Zhou, Yirong,Breit, Bernhard
-
supporting information
p. 18156 - 18160
(2017/12/13)
-
- Expanding the scope of the Babler–Dauben oxidation: 1,3-oxidative transposition of secondary allylic alcohols
-
We report the catalytic chromium-mediated oxidation of secondary allylic alcohols to give α,β-unsaturated aldehydes with exclusive (E)-stereoselectivity. This facile procedure employs catalytic PCC (5?mol?%) and periodic acid (H5IO6) as a co-oxidant. This transformation occurs specifically with aromatic substituted allyl alcohols containing both electron withdrawing and electron donating substituents as well as a range of functional groups.
- Killoran, Patrick M.,Rossington, Steven B.,Wilkinson, James A.,Hadfield, John A.
-
supporting information
p. 3954 - 3957
(2016/08/09)
-
- Tandem Benzylic Oxidation/Dihydroxylation of α-Vinyl- and α-Alkenylbenzyl Alcohols
-
A de novo tandem benzylic oxidative dihydroxylation of α-vinyl- and α-alkenylbenzyl alcohols has been developed to give α,β-dihydroxypropiophenones (=2,3-dihydroxy-1-phenylpropan-1-ones) and α,β-dihydroxyalkyl phenones. This method was shown to be substrate-selective and specific for the oxidation of benzylic alcohols.
- Fernandes, Rodney A.,Kattanguru, Pullaiah
-
-
- Divergent Gold(I)-Catalyzed Skeletal Rearrangements of 1,7-Enynes
-
The gold(I) complex catalyzed cycloisomerization and skeletal rearrangement of 1,n-enynes (n=5-7) is a powerful methodology for the efficient synthesis of complex molecular architectures. In contrast to 1,6-enynes, readily accessible homologous 1,7-enynes are largely unexplored in such transformations. Here, the divergent skeletal rearrangement of all-carbon 1,7-enynes by catalysis with a cationic gold(I) complex is reported. Depending on electronic and steric factors, differently substituted 1,7-enynes react via different carbocations formed from a common gold carbene intermediate to yield on the one hand novel exocyclic allenes and on the other hand tricyclic hexahydro-anthracenes through a novel dehydrogenative Diels-Alder reaction. Two birds with a gold-stone! Divergent gold(I) catalysis unraveled a novel cycloisomerization and a dehydrogenative Diels-Alder reaction of 1,7-enynes.
- Mei?, Rebecca,Kumar, Kamal,Waldmann, Herbert
-
supporting information
p. 13526 - 13530
(2015/09/22)
-
- Iridium-catalyzed enantioselective allylation of silyl enol ethers derived from ketones and α,β-unsaturated ketones
-
The unified Ir-catalyzed enantioselective allylic substitution reactions of silyl enol ethers derived from ketones and α,β-unsaturated ketones with branched, racemic allylic alcohols are described. This transformation is catalyzed by the Carreira system and proceeds without fluoride, and with high ee and b:l ratio. The synthetic utility of this method was illustrated by the concise enantioselective total synthesis of marine natural products calyxolane A, B and by the assignment of the absolute configuration of calyxolane A.
- Liang, Xiao,Wei, Kun,Yang, Yu-Rong
-
supporting information
p. 17471 - 17474
(2015/12/09)
-
- Ruthenium-catalyzed tandem-isomerization/asymmetric transfer hydrogenation of allylic alcohols
-
A one-pot procedure for the direct conversion of racemic allylic alcohols to enantiomerically enriched saturated alcohols is presented. The tandem-isomerization/ asymmetric transfer hydrogenation process is efficiently catalyzed by [{Ru(p-cymene)Cl2}2] in combination with the a-amino acid hydroxyamide ligand 1, and performed under mild conditions in a mixture of ethanol and THF. The saturated alcohol products are isolated in good to excellent chemical yields and in enantiomeric excess up to 93%.
- Slagbrand, Tove,Lundberg, Helena,Adolfsson, Hans
-
supporting information
p. 16102 - 16106
(2015/01/09)
-
- Direct, enantioselective iridium-catalyzed allylic amination of racemic allylic alcohols
-
The direct route: Iridium-catalyzed direct conversion of branched allylic alcohols into enantioenriched branched primary allylic amines is highly regio- and enantioselective (see scheme; coe=cyclooctene). Copyright
- Lafrance, Marc,Roggen, Markus,Carreira, Erick M.
-
supporting information; experimental part
p. 3470 - 3473
(2012/06/01)
-
- New inhibitors of colony spreading in Bacillus subtilis and Bacillus anthracis
-
We have recently characterized sliding motility in Bacillus subtilis strains that lack functional flagella, and here describe the discovery of inhibitors of colony spreading in these strains as well as the aflagellate pathogen, Bacillus anthracis. Aflagel
- Hao, Xin,Nguyen, Tam,Kearns, Daniel B.,Arpin, Carolynn C.,Fall, Ray,Sammakia, Tarek
-
scheme or table
p. 5583 - 5588
(2011/10/12)
-
- Kinetic resolution of allylic alcohols via stereoselective acylation catalyzed by lipase PS-30
-
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic allylic alcohols has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 968. Substituent effect is briefly discussed.
- Chen, Peiran,Xiang, Peng
-
supporting information; experimental part
p. 5758 - 5760
(2011/12/03)
-
- Ruthenium-catalyzed synthesis of allylic alcohols: Boronic acid as a hydroxide source
-
Secondary allylic alcohols were synthesized from linear allylic halides or carbonates using a catalytic amount of a ruthenium complex in the presence of boronic acid. The effects of solvent, base, ruthenium precursor, and boronic acid were fully explored, and the scope of the reaction was extended to various sub-strates. We also describe a preliminary investigation towards an enantioselective process.
- Bouziane, Asmae,Helou, Marion,Carboni, Bertrand,Carreaux, Francois,Demerseman, Bernard,Bruneau, Christian,Renaud, Jean-Luc
-
experimental part
p. 5630 - 5637
(2009/05/27)
-
- Pentamethylcyclopentadienyl ruthenium: an efficient catalyst for the redox isomerization of functionalized allylic alcohols into carbonyl compounds
-
The catalytic activity of the ruthenium(II) complex [RuCp*(CH3CN)3][PF6] 1 in the transposition of allylic alcohols into carbonyl compounds, in acetonitrile, is reported. This catalyst has proven to be able to catalyze the transformation of poorly reactive and/or functionalized substrates under smooth conditions.
- Bouziane, Asmae,Carboni, Bertrand,Bruneau, Christian,Carreaux, Fran?ois,Renaud, Jean-Luc
-
experimental part
p. 11745 - 11750
(2009/04/11)
-
- Tandem oxidation/halogenation of aryl allylic alcohols under Moffatt-Swern conditions
-
(Chemical Equation Presented) Aryl allylic alcohols are converted to halogenated unsaturated ketones or allylic halides using excess Moffatt-Swern reagent. Electron-poor aromatic rings favor formation of the halogenated ketone, while electron-donating substituents in the ortho or para positions favor formation of the allylic halide. The oxidation/halogenation reaction performs well with both oxalyl chloride and oxalyl bromide, providing access to the corresponding chlorides or bromides, respectively.
- Yin, Jiandong,Gallis, Christina E.,Chisholm, John D.
-
p. 7054 - 7057
(2008/02/11)
-
- [(NHC)Au1]-catalyzed rearrangement of allylic acetates
-
Equation Presented [(NHC)AuCl] complexes (NHC = N-heterocyclic carbene), in conjunction with a silver salt, were found to efficiently catalyze the rearrangement of allylic acetates under both conventional and microwave-assisted heating. The optimization of several reaction parameters (solvent, silver salt, and ligand) as well as a study of the reaction scope are reported. The steric hindrance of the ligand bound to gold was found crucial for the outcome of the reaction as only extremely bulky ligands permitted the isomerization.
- Marion, Nicolas,Gealageas, Ronan,Nolan, Steven P.
-
p. 2653 - 2656
(2008/02/09)
-
- Design, synthesis, and biological evaluation of cyclic and acyclic nitrobenzylphosphoramide mustards for E. coli nitroreductase activation
-
In efforts to obtain anticancer prodrugs for antibody-directed or gene-directed enzyme prodrug therapy using E. coli nitroreductase, a series of nitrobenzylphosphoramide mustards were designed and synthesized incorporating a strategically placed nitro gro
- Jiang, Yongying,Han, Jiye,Yu, Chengzhi,Vass, Simon O.,Searle, Peter F.,Browne, Patrick,Knox, Richard J.,Hu, Longqin
-
p. 4333 - 4343
(2007/10/03)
-
- A short enantioselective synthesis of (-)-chloramphenicol and (+)-thiamphenicol using tethered aminohydroxylation
-
An efficient enantioselective synthesis of (-)-chloramphenicol (1) and (+)-thiamphenicol (2) is described. These antibiotics have been synthesized from commercially available 4-nitrobenzaldehyde and 4-(methylthio)benzaldehyde, respectively, using tethered aminohydroxylation and Sharpless asymmetric epoxidation as the chirality inducing steps.
- George, Shyla,Narina, Srinivasarao V.,Sudalai, Arumugam
-
p. 10202 - 10207
(2007/10/03)
-
- Nitroaryl phosphoramide compositions and methods for targeting and inhibiting undesirable cell growth or proliferation
-
The present invention relates to nitroaryl-substituted phosphoramide prodrug compounds and methods of producing the same for use in targeting and inhibiting undesirable cell growth or proliferation.
- -
-
-
- A short stereoselective synthesis of (-)-chloramphenicol and (+)-thiamphenicol
-
A common strategy for the synthesis of (-)-chloramphenicol and (+)-thiamphenicol is described. These antibiotics have been synthesized from commercially available 4-nitrobenzaldehyde and 4-(methylthio)benzaldehyde in three and four steps, respectively.
- Bhaskar,Satish Kumar,Venkateswara Rao
-
p. 1279 - 1283
(2007/10/03)
-
- Nitroaryl Phosphoramides as Novel Prodrugs for E. coli Nitroreductase Activation in Enzyme Prodrug Therapy
-
Cyclic and acyclic nitroaryl phosphoramide mustard analogues were activated by E. coli nitroreductase, an enzyme explored in GDEPT. The more active acyclic 4-nitrobenzyl phosphoramide mustard (7) showed 167 500x selective cytotoxicity toward nitroreductase-expressing V79 cells with an IC50 as low as 0.4 nM. This is about 100x more active and 27x more selective than CB1954 (1). The superior activity was attributed to its better substrate activity (kcat/Km 19x better than 1) and/or excellent cytotoxicity of phosphoramide mustard released.
- Hu, Longqin,Yu, Chengzhi,Jiang, Yongying,Han, Jiye,Li, Zhuorong,Browne, Patrick,Race, Paul R.,Knox, Richard J.,Searle, Peter F.,Hyde, Eva I.
-
p. 4818 - 4821
(2007/10/03)
-
- Structure-activity relationships of (1'S)-1'-acetoxychavicol acetate, a major constituent of a Southeast Asian condiment plant Languas galanga, on the inhibition of tumor-promoter-induced Epstein-Barr virus activation
-
The structure-activity relationships of (1'S)-1'-acetoxychavicol acetate (ACA), a cancer chemopreventive agent of food origin, were investigated in an inhibitory test of tumor promoter teleocidin B-4-induced Epstein-Barr virus (EBV) activation in Raji cel
- Murakami, Akira,Toyota, Kazuo,Ohura, Shin,Koshimizu, Koichi,Ohigashi, Hajime
-
p. 1518 - 1523
(2007/10/03)
-