14565-11-8Relevant academic research and scientific papers
Investigation of (S)-(-)-acidomycin: A selective antimycobacterial natural product that inhibits biotin synthase
Bockman, Matthew R.,Engelhart, Curtis A.,Cramer, Julia D.,Howe, Michael D.,Mishra, Neeraj K.,Zimmerman, Matthew,Larson, Peter,Alvarez-Cabrera, Nadine,Park, Sae Woong,Boshoff, Helena I. M.,Bean, James M.,Young, Victor G.,Ferguson, David M.,Dartois, Veronique,Jarrett, Joseph T.,Schnappinger, Dirk,Aldrich, Courtney C.
, p. 598 - 617 (2019)
The synthesis, absolute stereochemical configuration, complete biological characterization, mechanism of action and resistance, and pharmacokinetic properties of (S)-(-)-acidomycin are described. Acidomycin possesses promising antitubercular activity against a series of contemporary drug susceptible and drug-resistant M. tuberculosis strains (minimum inhibitory concentrations (MICs) = 0.096-6.2 μM) but is inactive against nontuberculosis mycobacteria and Gram-positive and Gram-negative pathogens (MICs > 1000 μM). Complementation studies with biotin biosynthetic pathway intermediates and subsequent biochemical studies confirmed acidomycin inhibits biotin synthesis with a Ki of approximately 1 μM through the competitive inhibition of biotin synthase (BioB) and also stimulates unproductive cleavage of S-adenosyl-l-methionine (SAM) to generate the toxic metabolite 5′-deoxyadenosine. Cell studies demonstrate acidomycin selectively accumulates in M. tuberculosis providing a mechanistic basis for the observed antibacterial activity. The development of spontaneous resistance by M. tuberculosis to acidomycin was difficult, and only low-level resistance to acidomycin was observed by overexpression of BioB. Collectively, the results provide a foundation to advance acidomycin and highlight BioB as a promising target.
Synthesis of 2-normisoprostol, methyl6-(3-hydroxy-2-((E)-4-hydroxy-4- methyloct-1-enyl)-5-oxocyclopentyl)hexanoate
Harikrishna,Mohan, H. Rama,Dubey,Subbaraju, Gottumukkala V.
, p. 2763 - 2775 (2009)
Synthesis of 2-normisoprostol, methyl 6-(3-hydroxy-2-((E)-4-hydroxy-4- methyloct-1-enyl)-5-oxocyclopentyl)hexanoate (3), employing two-component coupling strategy based on 1,4-addition followed by DDQ-mediated triethyl silyl deprotection is reported. Desired key intermediates, methyl 6-(3-triethyl silyloxy-5-oxocyclopent-1-enyl)hexanoate (4) and (E)-1-(tributylstannyl)-4- methyloct-1-en-4-yloxy)triethylsilane (5), were prepared from commercially available cycloheptanone and propargyl bromide, and the intermediates were coupled to obtain 3 in a convergent approach.
Asymmetric Synthesis of Chiral 1,3-Dimethyl Units Through a Double Michael Reaction of Nitromethane and Crotonaldehyde Catalyzed by Diphenylprolinol Silyl Ether
Hayashi, Yujiro,Toda, Shunsuke
, p. 442 - 448 (2019)
An efficient synthetic route to install chiral 1,3-dimethyl units through a double Michael reaction of crotonaldehyde and nitromethane catalyzed by diphenylprolinol silyl ether is developed. Either 1,3- syn - or 1,3- anti -dimethyl units are obtained selectively depending on the enantiomer of the diphenylprolinol silyl ether catalyst used. The side chain of pneumocandin B 0 is synthesized enantioselectively by using the present method as a key step.
Stereoselective synthesis of MaR2n-3 DPA
S?nderskov, Jeanne,Tungen, J?rn E.,Palmas, Francesco,Dalli, Jesmond,Serhan, Charles N.,Stenstr?m, Yngve,Vidar Hansen, Trond
, (2020)
The first total synthesis of the n-3 docosapentaenoic derived oxygenated product MaR2n-3 DPA has been achieved. The 13R and 14S stereogenic centers were introduced using 2-deoxy-D-ribose in a chiral pool strategy. The geometry of the Z,E,E-triene moiety was prepared using highly E-selective Wittig- and Takai-olefination reactions as well as the Z-stereoselective Lindlar reduction. LC/MS-MS data of synthetic MaR2n-3 DPA matched data for the biosynthetic formed product that enabled the configurational assignment of this oxygenated natural product to be (7Z,9E,11E,13R,14S,16Z,19Z)-13,14-dihydroxydocosa-7,9,11,16,19-pentaenoic acid.
PEGylated Poly-HDACi: A Designer Polyprodrug from Optimized Drug Units**
Han, Jinghua,Wang, Da-Yuan,Wang, Qiuyu,Meng, Li,Luo, Zihan,Li, Jing,Kang, Yanke,Lv, Wenhui,Huang, Qingqing,Wang, Peng George,Wang, Yajie,Shen, Jie,Wang, Yanming
, (2021/12/22)
We designed, synthesized, and characterized a tri-block copolymer. Its hydrophobic part, a chain of histone deacetylase inhibitor (HDACi) prodrug, was symmetrically flanked by two identical PEG blocks, whereas the built-in HDACi was a linear molecule, terminated with a thiol at one end, and a hydroxyl group at the other. Such a feature facilitated end-to-end linkage of prodrugs through alternatively aligned disulfides and carbonates. The disulfides served dual roles: redox sensors of smart nanomedicine, and warheads of masked HDACi drugs. This approach, carefully designed to benefit both control-release and efficacy, is conceptually novel for optimizing drug units in nanomedicine. Micelles from this designer polyprodrug released only PEG, CO2 and HDACi, and synergized with DOX against HCT116 cells, demonstrating its widespread potential in combination therapy. Our work highlights, for the first time, the unique advantage of thiol-based drug molecules in nanomedicine design.
Total synthesis of the lipid mediator PD1n-3 DPA: Configurational assignments and anti-inflammatory and pro-resolving actions
Aursnes, Marius,Tungen, J?rn E.,Vik, Anders,Colas, Romain,Cheng, Chien-Yee C.,Dalli, Jesmond,Serhan, Charles N.,Hansen, Trond V.
supporting information, p. 910 - 916 (2014/05/20)
The polyunsaturated lipid mediator PD1n-3 DPA (5) was recently isolated from self-resolving inflammatory exudates of 5 and human macrophages. Herein, the first total synthesis of PD1n-3 DPA (5) is reported in 10 steps and 9% overall yield. These efforts, together with NMR data of its methyl ester 6, confirmed the structure of 5 to be (7Z,10R,11E,13E,15Z,17S,19Z)-10,17- dihydroxydocosa-7,11,13,15,19-pentaenoic acid. The proposed biosynthetic pathway, with the involvement of an epoxide intermediate, was supported by results from trapping experiments. In addition, LC-MS/MS data of the free acid 5, obtained from hydrolysis of the synthetic methyl ester 6, matched data for the endogenously produced biological material. The natural product PD1 n-3 DPA (5) demonstrated potent anti-inflammatory properties together with pro-resolving actions stimulating human macrophage phagocytosis and efferocytosis. These results contribute new knowledge on the n-3 DPA structure-function of the growing numbers of specialized pro-resolving lipid mediators and pathways.
Kinetic analysis of terminal and unactivated C-H bond oxyfunctionalization in fatty acid methyl esters by monooxygenase-based whole-cell biocatalysis
Schrewe, Manfred,Magnusson, Anders O.,Willrodt, Christian,Buehler, Bruno,Schmid, Andreas
experimental part, p. 3485 - 3495 (2012/03/26)
The alkane monooxygenase AlkBGT from Pseudomonas putida GPo1 constitutes a versatile enzyme system for the ω-oxyfunctionalization of medium chain-length alkanes. In this study, recombinant Escherichia coli W3110 expressing alkBGT was investigated as whole-cell catalyst for the regioselective biooxidation of fatty acid methyl esters to terminal alcohols. The ω-functionalized products are of general economic interest, serving as building blocks for polymer synthesis. The whole-cell catalysts proved to functionalize fatty acid methyl esters with a medium length alkyl chain specifically at the ω-position. The highest specific hydroxylation activity of 104 U gCDW-1 was obtained with nonanoic acid methyl ester as substrate using resting cells of E. coli W3110 (pBT10). In an optimized set-up, maximal 9-hydroxynonanoic acid methyl ester yields of 95% were achieved. For this specific substrate, apparent whole-cell kinetic parameters were determined with a Vmax of 204±9 U gCDW -1, a substrate uptake constant (KS) of 142±17 μM, and a specificity constant Vmax/KS of 1.4 U g CDW-1 μM-1 for the formation of the terminal alcohol. The same E. coli strain carrying additional alk genes showed a different substrate selectivity. A comparison of biocatalysis with whole cells and enriched enzyme preparations showed that both substrate availability and enzyme specificity control the efficiency of the whole-cell bioconversion of the longer and more hydrophobic substrate dodecanoic acid methyl ester. The efficient coupling of redox cofactor oxidation and product formation, as determined in vitro, combined with the high in vivo activities make E. coli W3110 (pBT10) a promising biocatalyst for the preparative synthesis of terminally functionalized fatty acid methyl esters. Copyright
Structure-activity relationship study of flowering-inducer FN against Lemna paucicostata
Kai, Kenji,Takeuchi, Jun,Kataoka, Taichi,Yokoyama, Mineyuki,Watanabe, Naoharu
, p. 6760 - 6769 (2008/12/21)
FN1 (1) and FN2 (2), cycloadducts of α-ketol octadecadienoic acid (3) with norepinephrine (NE), induce flowering in Lemna paucicostata. In order to broaden our understanding of structural requirements of FN?for flower induction, nine analogs of 3 (4-12) were synthesized and reacted with NE under basic conditions. These analogs, except for 8, 10, and 12, exhibited significant activity regarding to floral induction in L. paucicostata. Similar experiments were carried out by using 3 and epinephrine, and it was demonstrated that these products also possessed biological activity.
Reductive Cyclization of Ketones Tethered to Activated Olefins Mediated by Magnesium in Methanol
Lee, Ge Hyeong,Choi, Eun Bok,Lee, Eun,Pak, Chwang Siek
, p. 1428 - 1443 (2007/10/02)
The reductive cyclization of various ketones tethered to activated olefins such as α,β-unsaturated esters, nitriles, sulfoxides, and sulfides mediated by magnesium in dry methanol in the presence of mercuric chloride.When traeted with magnesium in dry methanol at -23 deg C all of the ketones except nitrile 9 (42percent) and 5-oxa-8-keto-2-enoate 5 (13percent) gave excellent yields (79-98percent) of mono- and bicyclic alcohol products resulting from carbon-carbon bond formation between the β-carbon of the activated olefin and the carbonyl carbon.The reaction was accelerated by the catalytic amount of mercuric chloride, although the stereoselectivity was not affected by the catalyst.For all the substrates except 8-keto-2-enoate 3 and 5-aza-8-keto-2-enoate 6, the configuration of the major product was trans between the hydroxy and (methoxycarbonyl)methyl groups.The product isomer ratios were independent of the substrate geometry (E or Z).In contrast to the ketones, aldehydes tethered to α,β-unsaturated esters gave products of simple reduction of the double bond and/or saturated alcohols instead of the cyclized products.When the reaction temperature was lowered, the yields of cyclized product were significantly affected by the production of appreciable amounts of saturated product, but the stereoselectivity was not improved.Under the same reaction conditions α,β-unsaturated sulfoxide 16 gave deoxygenated sulfide 18 (85percent) as the major product along with a small amount (9percent) of cyclized product 19t.In contrast, sulfone 17 underwent desulfonylation instead of cyclization to give olefin 20 (54percent).With excess magnesium (15 equiv), however, α,β-unsaturated sulfoxide 16 gave cyclized sulfide 19t (95percent) via deoxygenated sulfide 18.Both 16Z and 16E afforded product 19t as a single isomer.It is suggested that the reductive cyclization of the α,β-unsaturated esters and nitriles proceed by means of nucleophilic attack of a β-carbon radical anion, formed by initial electron transfer from magnesium metal to the activated olefin, on the carbonyl group.The cyclization of the α,β-unsaturated sulfide proceeds by nucleophilic attack of the ketyl on the olefinic double bond.
Intramolecular palladium-catalysed cross coupling; a direct route to γ-oxo-α,β-unsaturated macrocycles
Baldwin, Jack E.,Adlington, Robert M.,Ramcharitar, Steve H.
, p. 2957 - 2976 (2007/10/02)
Intramolecular Pd0-catalysed cross coupling of structures terminating in an acyl chloride and a β-stannylalkenoate has provided a new and an efficient route to 10-20 membered γ-oxo-α,β-unsaturated macrolides. Both the Z and E-β-stannylalkenoates afforded identical macrocyclic products demonstrating that under the reaction conditions thermodynamic equilibration of the first formed cross coupled product was most probably occurring. The method has been used to synthesise the macrocylic framework of the antibiotic A26771B and norpatulolide B.
