2351-90-8Relevant academic research and scientific papers
Synthesis and Biological Evaluation of Hoshionolactam-Based Compounds
Elizebath, Drishya,Jachak, Gorakhnath R.,Reddy, D. Srinivasa,Shanmugam, Dhanasekaran,Shukla, Anurag
, p. 2212 - 2218 (2021)
In search of novel antitrypanosomal agents based on hoshinolactam (IC50=3.9 nM), we disclose the synthesis and biological evaluations of 14 different analogues of the natural product using combinations of different acids and lactams. Antitrypanosomal activity assays revealed that the synthesized analogues were less potent than the parent natural product.
A new procedure for Horner-Wadsworth-Emmons olefination of carbonyl compounds
Bonadies, Francesco,Cardilli, Antonella,Lattanzi, Alessandra,Orelli, Liliana R.,Scettri, Arrigo
, p. 3383 - 3386 (1994)
Aldehydes undergo an efficient E-stereoselective Horner-Wadsworth-Emmons olefination by generation of phosphonate carbanion with lithium hydroxide. The reaction proceeds satisfactorily with linear, cyclic, polifunctional ketones in the presence of activated zeolites and by the slow addition of the base.
Experimental evidence for a [2 + 2] mechanism in the Lewis acid-promoted formation of α,β-unsaturated esters from ethoxyacetylene and aldehydes. Synthesis and characterisation of 4-ethoxyoxetes
Oblin, Magali,Parrain, Jean-Luc,Rajzmann, Michel,Pons, Jean-Marc
, p. 1619 - 1620 (1998)
4-Ethoxy-2H-oxetes 3a-c were prepared from ethoxyacetylene and alkoxy aldehydes 1a-c through MgBr2-Et2O promoted [2 + 2] cycloaddition reaction and were characterized at room temperature; their synthesis, which could occur via the formation of a chelate, establishes cycloaddition as the initial step in the formation of α,β-unsaturated esters 4a-c.
A One-Pot Synthesis of α,β-Unsaturated Esters From Esters
Hong, Chang Whee,Lee, Yong Jin,An, Duk Keun
, p. 1121 - 1125 (2021/06/01)
A convenient method for reductive Horner–Wadsworth–Emmons (HWE) olefination is described. The E-selective HWE homologation of various esters to α,β-unsaturated esters was readily achieved and gave the desired products in good-to-moderate yields under mild conditions. The one-pot reaction proceeds through an in situ generated aldehyde, formed via the partial reduction of an ester with lithium diisobutyl-t-butoxyaluminum hydride. The formation of cyclized metal acetal and subsequent decompose to the aldehyde for the olefination was found to be a crucial step in this C2-carbon homologation protocol.
Phosphorus-recycling wittig reaction: Design and facile synthesis of a fluorous phosphine and its reusable process in the wittig reaction
Yamamoto, Yuki,Kawaguchi, Shin-Ichi,Nishimura, Misaki,Sato, Yuki,Shimada, Yoshihisa,Tabuchi, Akihiro,Nomoto, Akihiro,Ogawa, Akiya
, p. 14684 - 14696 (2020/11/30)
This study shows that phosphorus sources can be recycled using the appropriate fluorous phosphine in the Wittig reaction. The designed fluorous phosphine, which has an ethylene spacer between its phosphorus atom and the perfluoroalkyl group, was synthesized from air-stable phosphine reagents. The synthesized phosphine can be used for the Wittig reaction process to obtain various alkenes in adequate yields and stereoselectivity. The concomitantly formed fluorous phosphine oxide was extracted from the reaction mixture using a fluorous biphasic system. The fluorous phosphine was regenerated by reducing the fluorous phosphine oxide with diisobutylaluminum hydride. Finally, a series of gram scale phosphorus recycling processes were performed, which included the Wittig reaction, separation, reduction, and reuse.
CuBr2-catalyzed diastereoselective allylation: Total synthesis of decytospolides A and B and their C6-epimers
Choudhury, Utkal Mani,Mallampudi, N. Arjunreddy,Mohapatra, Debendra K.,Padhi, Birakishore,Reddy, G. Sudhakar
, p. 2685 - 2695 (2020/04/17)
An efficient CuBr2-catalyzed diastereoselective allylation of a cyclic hemiacetal with allyltrimethylsilane as a nucleophile has been developed. The protocol offers a cost effective, protecting group tolerant, and operationally simple approach to 2,6-trans-disubstituted tetrahydropyran with excellent diastereoselectivity. Furthermore, the application of this methodology has been demonstrated in the total synthesis of decytospolides A and B and their C6-epimers.
Stereoselective Synthesis of C1–C7 and C6–C22 Fragments of Phostriecin, Goniothalamines, and Their Analogues
Purushotham Reddy,Vasudeva Reddy,Sabitha, Gowravaram
, p. 4389 - 4399 (2018/09/11)
The stereoselective synthesis of two fragments (C1–C7 and C6–C22) of the anti-tumor agent phostriecin has been achieved. The chiral hydroxy-vinyl-δ-lactone building block (fragment C1–C7) was subsequently utilized for the synthesis of 5-hydroxygoniothalamin, 5-acetoxygoniothalamin, and their derivatives.
Synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases
Brodl, Eveline,Ivkovic, Jakov,Tabib, Chaitanya R.,Breinbauer, Rolf,Macheroux, Peter
, p. 1487 - 1495 (2017/02/18)
Bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490?nm. In this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. These α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. The luciferase of Photobacterium leiognathi was found to convert these analogs and showed a reduced but significant bioluminescence activity compared to tetradecanal. This study showed the trend that aldehydes, both saturated and unsaturated, with longer chain lengths had higher activity in terms of bioluminescence than shorter chain lengths. The maximal light intensity of (E)-tetradec-2-enal was approximately half with luciferase of P. leiognathi, compared to tetradecanal. Luciferases of Vibrio harveyi and Aliivibrio fisheri accepted these newly synthesized substrates but light emission dropped drastically compared to saturated aldehydes. The onset and the decay rate of bioluminescence were much slower, when using unsaturated substrates, indicating a kinetic effect. As a result the duration of the light emission is doubled. These results suggest that the substrate scope of bacterial luciferases is broader than previously reported.
Asymmetric Total Syntheses of Two Possible Diastereomers of Gliomasolide e and Its Structural Elucidation
Reddy, Ramidi Gopal,Venkateshwarlu, Ravula,Ramakrishna, Kallaganti V. S.,Yadav, Jhillu S.,Mohapatra, Debendra K.
, p. 1053 - 1063 (2018/06/18)
The first total syntheses of two possible diastereomers of gliomasolide E, a 14-membered macrolides isolated from the marine sponge Phakellia fusca Thiele, which was collected from the South China Sea, is reported. Highlights of the synthesis include macrolactonization through intramolecular Horner-Wadsworth-Emmons olefination, Yamaguchi-Hirao alkynylation, and base-induced elimination reactions for propargyl alcohol synthesis as the key reactions. Detailed comparison of their 1H and 13C NMR (1D and 2D NMR data) and specific rotation with those of the natural product revealed that the absolute stereochemistry of gliomasolide E should be (2E,5R,7R,9R,13R).
Selective Hydrogenation of Functionalized Alkynes to (E)-Alkenes, Using Ordered Alloys as Catalysts
Furukawa, Shinya,Komatsu, Takayuki
, p. 2121 - 2125 (2016/03/15)
Intermetallic Pd3Pb acts as a highly selective alkyne semihydrogenation catalyst that is greatly superior to the conventional Lindlar catalyst. Density functional theory (DFT) calculations demonstrate an ideal adsorption property of Pd3Pb, where the surface holds alkynes while releasing alkenes. A tandem catalytic system that is comprised of Pd3Pb/SiO2 for alkyne semihydrogenation and RhSb/SiO2 for alkene isomerization allows one-pot (E)-alkene synthesis from a functionalized alkyne, which is the first success using heterogeneous catalysts. A variety of functionalized alkynes with aldehyde, ketone, carboxylic acid, and ester moieties are hydrogenated into the corresponding (E)-alkene in good to excellent yields under 1 atm H2 at room temperature.
