18202-11-4Relevant academic research and scientific papers
Effect of Tellurium Position on the Myocardial Uptake of Radioiodinated 18-Iodotellura-17-octadecenoic Acid Analogues
Knapp, F.F.,Srivastava, P.C.,Callahan, A.P.,Cunningham, E.B.,Kabalka, G.W.,Sastry, K.A.R.
, p. 57 - 63 (1984)
The effect of tellurium (Te) position on myocardial specifity and retention of fatty acids in which radioiodide is stabilized as a trans-(E)-vinyl iodode has been evaluated in rats.Five analogues of 18-iodo-17-octadecenoic acid (ICH=CH-R-Te-R'-COOH) with Te at positions 5,7,9,11, and 13 were prepared by coupling of a trans-diiodoalkene (ICH=CH-R-I) with the requisite sodium telluride substrate (NaTe-R'-COOR''; R''=Me or Et), followed by basic hydrolysis.By varying R and R', a series of analogues with a chain length of 18 carbon atoms was prepared.T he telluride substrates were generated in situ by NaBH4 reduction of the corresponding ditellurides, and the diiodoalkenes were prepared by sodium iodide-chloramine-T treatment of the corresponding vinylboronic acids .The vinylboronic acids were prepared by treatment of the terminal acetylenes (HCC-R-I), synthesized from commercially available materials, with catecholborane.All new compounds were analyzed by TLC, NMR, MS, and elemental analyses.The 125I analogues were prepared in the same manner and evaluated in rats (four per group).Heart uptake and retention were dependent upon the Te position.The analogue with Te at position 5 showed the most pronounced (5-min values) heart uptake (3.7-4.1 dose/g), myocardial retention, and heart/blood ratios (37:1) and is a candidate for radiolabeling with 123I and further evaluation as a myocardial imaging agent.
Synthesis of pyrinodemins A and B. Assignment of the double bond position of pyrinodemin A
Snider, Barry B.,Shi, Bo
, p. 1639 - 1642 (2001)
Condensation of aldehyde 3a with hydroxylamine 4b afforded nitrone 2, which underwent an intramolecular cycloaddition to give 1b, the proposed structure of pyrinodemin A. A similar condensation of aldehyde 3a and hydroxylamine 4a provided pyrinodemin A (1a), which has the double bond one carbon further away from the isoxazolidine. An analogous sequence gave pyrinodemin B (21).
Streamlined One-Pot Synthesis of Nitro Fatty Acids
El Rady, Eman A.,Hassan, Mohamed,Krieg, Sara-Cathrin,Maier, Thorsten J.,Manolikakes, Georg,Ndefo Nde, Cedric,Raslan, Mohamed A.,Roos, Jessica,Sadek, Kamal U.
, p. 2239 - 2252 (2021)
A novel method for the synthesis of nitro fatty acids (NFAs), an intriguing class of endogenously occurring lipid mediators, is reported. This one-pot procedure enables the controlled and stereoselective construction of nitro fatty acids from a simple set of common building blocks in a highly facile manner. Thereby, this methodology offers a streamlined, highly modular access to naturally occurring nitro fatty acids as well as non-natural NFA derivatives.
Straightforward synthesis of a double-lasso macrocycle from a nonsymmetrical [c2]daisy chain
Romuald, Camille,Cazals, Guillaume,Enjalbal, Christine,Coutrot, Frédéric
, p. 184 - 187 (2013)
The straightforward synthesis of a double-lasso macrocycle from a nonsymmetrical [c2]daisy chain, using the copper(I)-catalyzed Huisgen alkyne-azide 1,3-dipolar cycloaddition, is described. The preparation of the nonsymmetrical alkyne azide [c2]daisy chain precursor was realized in situ via the exchange of the monomers contained in both symmetrical alkyne and azide [c2]daisy chains and was followed by mass spectrometry.
The Effect of Two-dimensional Ordering on Photoreactions of Long-chain Unsaturated Carboxylic Acids
Guo, Bo Zhang,Tripathi, Sadhana,Taylor, D. Martin,Stirling, Charles J. M.
, p. 479 - 481 (1991)
Long chain alkanoic acids with terminal alkenyl and alkynyl groups are subjected to UV irradiation in ordered (Langmuir-Blodgett) and disordered films; polymerisation occurs in the LB films but only dissociation and desorption in the disordered films.
LIPOSOME FORMULATION
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Page/Page column 18, (2020/12/30)
The present invention describes liposome formulations comprising a phospholipid, cholesterol and a fatty acid compound or fatty acid containing compound. Also, various medical uses of the liposome formulation are described.
Synergistic Gold and Copper Dual Catalysis for Intramolecular Glaser–Hay Coupling: Rapid Total Synthesis of Ivorenolide B
Rangaraju, Sudheer K.,Gonela, Uma Maheshwar,Kavita, Aala,Yadav, Jhillu S.,Mohapatra, Debendra K.
supporting information, p. 4376 - 4380 (2018/09/11)
A synergistic dual catalysis approach involving gold and copper catalysts for the synthesis of macrolactones bearing 1,3-butadiynes through an intramolecular Glaser–Hay coupling reaction in good yield is described. This dual catalytic system exhibited good selectivity, reactivity and functional group tolerance. This unique process offers a paradigm shift: the potential as well as the versatility of this novel method is not only exemplified for the synthesis of macrolactones of different ring size but also for the rapid total synthesis of ivorenolide B, a new class of macrolides endowed with conjugated 1,3-diyne motif, having impressive immunosuppressive activities.
Total Synthesis and Structural Elucidation of Two Unusual Non-Methylene-Interrupted Fatty Acids in Ovaries of the Limpet Cellana toreuma
Shimada, Kazuaki,Sugawara, Ayako,Korenaga, Toshinobu,Kawashima, Hideki
, p. 1019 - 1032 (2017/10/07)
In our previous study, unusual odd-numbered dienoic acids with a terminal olefin were found as minor components in ovaries of the Japanese limpet Cellana toreuma, and the synthetic interests have been focused onto their structural confirmation and the inspection into their potential biological activity. Here, we describe an efficient and stereoselective total synthesis of two new unusual dienoic acids, 19:2?7,18 and 21:2?7,20, through a common pathway involving the strategic combination of alkyne-zipper reaction and Lindlar hydrogenation for the construction of their unique carbon chains. In our synthetic study, 2-propyn-1-ol was at first subjected to alkylation and alkyne-zipper reaction to form the two fragments, and the subsequent carbon chain elongation was achieved by the usual coupling reaction to obtain the C-19 and C-21 products bearing an internal acetylenic group. Then, the internal acetylenic group of these products was subjected to Lindlar hydrogenation to form a Z-alkenyl moiety, and the subsequent deprotection of the products was carried out under an acidic condition without isomerization of the internal Z-alkenyl group. Total synthesis of target fatty acids, 19:2?7,18 and 21:2?7,20, was finally accomplished by two-step oxidation of the resulting alcohols into carboxylic acids in a highly chemoselective manner, and the structures of these unusual natural fatty acids were finally elucidated by identifying the GC–MS spectra of the methyl esters of authentic and synthetic fatty acids.
α-Amino Aldehydes as Readily Available Chiral Aldehydes for Rh-Catalyzed Alkyne Hydroacylation
Hooper, Joel F.,Seo, Sangwon,Truscott, Fiona R.,Neuhaus, James D.,Willis, Michael C.
supporting information, p. 1630 - 1634 (2016/02/20)
Readily available α-amino aldehydes, incorporating a methylthiomethyl (MTM) protecting group on nitrogen, are shown to be efficient substrates in Rh-catalyzed alkyne hydroacylation reactions. The reactions are performed under mild conditions, employing a small-bite-angle bis-phosphine ligand, allowing for good functional group tolerance with high stereospecificity. Amino aldehydes derived from glycine, alanine, valine, leucine, phenylalanine, isoleucine, serine, tryptophan, methionine, and cysteine were successfully employed, as was an enantiomerically enriched α-OMTM-aldehyde derived from phenyllactic acid. The synthetic utility of the α-amino enone products is demonstrated in a short enantioselective synthesis of the natural product sphingosine.
Enantioselective Rhodium-Catalyzed Atom-Economical Macrolactonization
Ganss, Stephanie,Breit, Bernhard
supporting information, p. 9738 - 9742 (2016/08/10)
A highly attractive route toward macrolactones, which form the cyclic scaffold of a multitude of diverse natural compounds, is described. Although many chemical approaches to this structural motif have been explored, an asymmetric variant of the cyclization is unprecedented. Herein we present an enantioselective macrolactonization through an intramolecular atom-economical rhodium-catalyzed coupling of ω-allenyl-substituted carboxylic acids. The use of a modified diop ligand, chiral DTBM-diop, led to high enantioselectivity (up to 93 % ee). The reaction tolerated a large variety of functionalities, including α,β-unsaturated carboxylic acids and depsipeptides, and provided the desired macrocycles with very high enantio- and diastereoselectivity.
