7554-28-1Relevant articles and documents
A Concise Stereoselective Total Synthesis of Methoxyl Citreochlorols and Their Structural Revisions
Sunnapu, Ranganayakulu,Rajendar, Goreti
, p. 1637 - 1642 (2021/03/15)
A concise, stereoselective and protecting group free approaches for the total synthesis of (?)-(2S,4R)- and (+)-(2R,4S)-3′-methoxyl citreochlorols and their stereoisomers are demonstrated. All four stereoisomers were synthesized to establish the absolute stereochemistry of the reported structures and the structures were revised accordingly. The approach involves chelation controlled regioselective reduction of a diester, silyl iodide promoted ring-opening iodo esterification of lactones, highly chemo- and regioselective ring-opening of an epoxy ester, dichloromethylation of a carboxyl group, and syn- and anti-selective reduction of the resulted β-hydroxy ketone as key steps.
Stereoselective Synthesis of Coreoside D and Determination of Its Absolute Configuration
Imaizumi, Ryoya,Ogawa, Narihito
supporting information, p. 1409 - 1412 (2020/11/23)
We report the stereoselective synthesis of (3 S)- and (3 R)-coreoside D. The conjugated diyne in the C1-C14 moiety was synthesized through two types of palladium-catalyzed cross-coupling reaction. The introduction of the glucopyranose was achieved by a gl
Plant growth regulators and Axl and immune checkpoint inhibitors from the edible mushroom Leucopaxillus giganteus
Choi, Jae-Hoon,D’Alessandro-Gabazza, Corina N.,Gabazza, Esteban C.,Harada, Etsuko,Hirai, Hirofumi,Kawagishi, Hirokazu,Malya, Irine Yunhafita,Toda, Masaaki,Wu, Jing,Yasuma, Taro
, p. 1332 - 1338 (2020/03/31)
A novel compound, (R)-4-ethoxy-2-hydroxy-4-oxobutanoic acid (1), and six known compounds (2–7) were isolated from the fruiting bodies of the wild edible mushroom Leucopaxillus giganteus. The planar structure of 1 was determined by the interpretation of spectroscopic data analysis. The absolute configuration of 1 was determined by comparing specific rotation of the synthetic compounds. In the plant regulatory assay, the isolated compounds (1–7) and the chemically prepared compounds (8–10) were evaluated their biological activity against the lettuce (Lactuca sativa) growth. Compounds 1 and 3–10 showed the significant regulatory activity of lettuce growth. 1 showed the strongest inhibition activity among the all the compounds tested. In the lung cancer assay, all the compounds were assessed the mRNA expression of Axl and immune checkpoints (PD-L1, PD-L2) in the human A549 alveolar epithelial cell line by RT-PCR. Compounds 1–10 showed significant inhibition activity against Axl and/or immune checkpoint.
A cross-metathesis approach to novel pantothenamide derivatives
Guan, Jinming,Hachey, Matthew,Puri, Lekha,Howieson, Vanessa,Saliba, Kevin J.,Auclair, Karine
supporting information, p. 963 - 968 (2016/07/06)
Pantothenamides are known for their in vitro antimicrobial activity. Our group has previously reported a new stereoselective route to access derivatives modified at the geminal dimethyl moiety. This route however fails in the addition of large substituents. Here we report a new synthetic route that exploits the known allyl derivative, allowing for the installation of larger groups via cross-metathesis. The method was applied in the synthesis of a new pantothenamide with improved stability in human blood.
Visible light photoredox-catalyzed deoxygenation of alcohols
Rackl, Daniel,Kais, Viktor,Kreitmeier, Peter,Reiser, Oliver
supporting information, p. 2157 - 2165 (2015/01/09)
Carbon-oxygen single bonds are ubiquitous in natural products whereas efficient methods for their reductive defunctionalization are rare. In this work an environmentally benign protocol for the activation of carbon-oxygen single bonds of alcohols towards a reductive bond cleavage under visible light photocatalysis was developed. Alcohols were activated as 3,5-bis(trifluoromethyl)-substituted benzoates and irradiation with blue light in the presence of [Ir(ppy)2( dtb-bpy)](PF6 ) as visible light photocatalyst and Hünig's base as sacrificial electron donor in an acetonitrile/water mixture generally gave good to excellent yields of the desired defunctionalized compounds. Functional group tolerance is high but the protocol developed is limited to benzylic, α-carbonyl, and α-cyanoalcohols; with other alcohols a slow partial C-F bond reduction in the 3,5-bis(trifluoromethyl)benzoate moiety occurs.
Radical-mediated intramolecular C-C bond formation and the deoxygenation of alcohols under solvent-free conditions with tributyl methyl ammonium hypophosphite
Lee, Eun Hwa,Cho, Dae Hyan,Satyender, Apuri,Jang, Doo Ok
scheme or table, p. 6927 - 6929 (2012/02/05)
A green, solvent-free protocol was developed for the radical-mediated intramolecular cyclization of haloacetals and the deoxygenation of S-methyl dithiocarbonates and cyclic thionocarbonate. This process uses tributyl methyl ammonium hypophosphite as a H-donor in the presence of triethylborane or t-butyl peroxide. This methodology provides eco-friendly reaction conditions.
Geminal dialkyl derivatives of N-substituted pantothenamides: Synthesis and antibacterial activity
Akinnusi, T. Olukayode,Vong, Kenward,Auclair, Karine
scheme or table, p. 2696 - 2706 (2011/06/17)
As a key precursor of coenzyme A (CoA) biosynthesis, pantothenic acid has proven to be a useful backbone to elaborate probes of this biosynthetic pathway, study CoA-utilizing systems, and design molecules with antimicrobial activity. The increasing prevalence of bacterial strains resistant to one or more antibiotics has prompted a renewed interest for molecules with a novel mode of antibacterial action such as N-substituted pantothenamides. Although numerous derivatives have been reported, most are varied at the terminal N-substituent, and fewer at the β-alanine moiety. Modifications at the pantoyl portion are limited to the addition of an ω-methyl group. We report a synthetic route to N-substituted pantothenamides with various alkyl substituents replacing the geminal dimethyl groups. Our methodology is also applicable to the synthesis of pantothenic acid, pantetheine and CoA derivatives. Here a small library of new N-substituted pantothenamides was synthesized. Most of these compounds display antibacterial activity against sensitive and resistant Staphylococcus aureus. Interestingly, replacement of the ProR methyl with an allyl group yielded a new N-substituted pantothenamide which is amongst the most potent reported so far.
Synthesis and biophysical studies on 35-Deoxy amphotericin b methyl ester
Szpilman, Alex M.,Cereghetti, Damiano M.,Manthorpe, Jeffrey M.,Wurtz, Nicholas R.,Carreira, Erick M.
supporting information; experimental part, p. 7117 - 7128 (2010/03/05)
The use of molecular editing in the elucidation of the mechanism of action of amphotericin B is presented. A modular strategy for the synthesis of amphotericin B and its designed analogues is developed, which relies on an efficient gram-scale synthesis of various subunits of amphotericin B. A novel method for the coupling of the mycosa-mine to the aglycone was identified. The implementation of the approach has enabled the preparation of 35-deoxy amphotericin B methyl ester. Investigation of the antifungal activity and efflux-inducing ability of this amphotericin B congener provided new clues to the role of the 35-hydroxy group and is consistent with the involvement of double barrel ion channels in causing electrolyte efflux. 2009 Wiley-VCH Verlag GmbH & Co. KGaA.
Synthesis of 35-deoxy amphotericin B methyl ester: A strategy for molecular editing
Szpilman, Alex M.,Cereghetti, Damiano M.,Wurtz, Nicholas R.,Manthorpe, Jeffrey M.,Carreira, Erick M.
supporting information; experimental part, p. 4335 - 4338 (2009/02/08)
(Chemical Presented) A modular strategy for the assembly of amphotericin B analogues with modifications in the macrolactone ring relies on the efficient gram-scale synthesis of all major and minor motifs of amphotericin B. Proof of concept has been achieved by the preparation of the 35-deoxy aglycone en route to the long-sought-after 35-deoxy analogue of amphotericin B.
A one-pot combination of amine and heterocyclic carbene catalysis: direct asymmetric synthesis of β-hydroxy and β-malonate esters from α,β-unsaturated aldehydes
Zhao, Gui-Ling,Córdova, Armando
, p. 5976 - 5980 (2008/02/10)
The one-pot combination of amine and heterocyclic carbene catalysis (AHCC) enabled the synthesis of β-hydroxy, β-malonate and β-amino esters from α,β-unsaturated aldehydes with high enantioselectivity (91-97% ee).
