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Objective: Dehydroepiandrosterone plays an important role in the human beings due to its ability to be converted into androgens and oestrogens. The aim of this paper is to synthesize a series of novel dehydroepiandrosteronyl 1,2,3-triazole derivatives and study the antitumor activity of the synthesized compounds. Methods: Novel dehydroepiandrosteronyl 1,2,3-triazole derivatives were synthesized across the Mitsunobu and click reaction, respectively. The cytotoxicities of the synthesized compounds against HeLa, HGC-27, and HEK-293T cells were determined by MTT assay. Results and Discussion: The results showed that compound (V) (3R,8R,9S,10R,13S,14S)3-(4-(4-methoxyphenyl)-1H-1,2,3-triazol-1-yl)-10,13-dimethyl-1,2,3,4,7,8,9,10,11,12,13,14,15,16-tetradecahydro17H-cyclopenta[a]phenanthren-17-one had better inhibitory activity against the tumor cell lines tested. The IC50 value of inhibitory activity on human cervical cancer cell (HeLa) and human gastric cancer cell (HGC-27) was 33.6 and 22.3 μmolL–1, respectively. Conclusions: This work provides useful strategies for the design and synthesis of new steroidal antitumor drugs. The synthesized compounds have certain inhibitory activity on tumor cell growth and proliferation, but have little damage on normal cells, which deserves further study. [ABSTRACT FROM AUTHOR]

A practical synthesis of (±)-entecavir has been developed on the basis of Corey (±)-lactone diol. The key stage is the synthesis of (1R*,3R*,4S*)-4-(1-ethoxyethoxy)-3-[(1-ethoxyethoxy)methyl]-2-methylidene-cyclo-pentan-1-ol by oxidative decarboxylation of 2-{(1S*,2R*,3S*,5R*)-5-{[tert-butyl(dimethyl)silyl]oxy}-3-(1-ethoxyethoxy)-2-[(1-ethoxyethoxy)methyl]cyclopentyl}acetic acid with lead tetraacetate. [ABSTRACT FROM AUTHOR]

Keywords: Arabinoxylan ferulate; Biomass; Carbohydrates; Mitsunobu reaction; Synthetic methods; Xylotriose model; Reducing end-groups EN Arabinoxylan ferulate Biomass Carbohydrates Mitsunobu reaction Synthetic methods Xylotriose model Reducing end-groups 7389 7392 4 08/16/23 20230801 NES 230801 Maintext In our recent article (Elschner et al. [4]), we reported about the Mitsunobu esterification of arabinoxylan with ferulic acid at position 5 of the arabinose side chain. The standard Mitsunobu reaction for the esterification of carboxylic acids with alcohols takes place according to a dehydrative S SB N sb 2 process enabled by reductive triphenylphosphine and diisopropyl azodicarboxylate as oxidant. [Extracted from the article]

Arabinoxylan ferulate representing a macromolecular LCC model valid for annual plants is synthesized under Mitsunobu conditions. The content of ferulic acid ester is tuned by the reaction conditions achieving degree of substitution values from 0.09 to 0.45. Utilization of the chloride-free solvent N-methyl-2-pyrrolidone allows the design of pure Mitsunobu products without occurrence of deoxychloro moieties arising from Appel type reaction. 2D NMR experiments reveal nature-identical structure of ferulate moieties present at position 5 of the arabinose side chain. Enzymatic dehydrogenation polymerization of coniferyl alcohol on ferulate anchor groups under homogeneous conditions lead to β -O-4, β -5, and Hibbert ketone structures identified by Py-GC-MS. The results are valuable to study structure-property relationships within the formation of natural and non-native lignins. [ABSTRACT FROM AUTHOR]

The Mitsunobu reaction of tris(2-hydroxyphenyl)phosphine oxide with 3-butyn-1-ol has afforded bis[2-(3′′-butynyloxy)phenyl](2′-hydroxyphenyl)phosphine oxide, which has been converted into the corresponding triazole via click reaction with PhN3. Asymmetric tripodal ligand containing three 1,2,3-triazole groups in the molecule has been prepared from this triazole via the reaction with propargyl bromide and PhN3. Structure of the ligand has been elucidated by means of single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Novel di- and tetra-substituted calix[4]arene derivatives bearing diacetylene moieties at the lower rim of macrocycle were synthesized via the Mitsunobu and Williamson reactions. The dealkylation of diacetylene moieties of calix[4]arene was for the first time discovered in the DMSO—hydrazine hydrate system. An important role in the dealkylation of diacetylene moieties is played by neighboring unsubstituted OH groups at the macrocycle. Blocking of OH groups with butyl substituents and elongation of the linker between the butadiynyl fragments and the macrocyclic platform significantly reduce the affinity of macrocycle to reductive cleavage. The unique reactivity of calix[4]arene in its reaction with hydrazine hydrate was demonstrated in comparison with a model conjugate of diacetylene with 4-tert-butylphenol. The reductive cleavage may proceed via the formation of pyrazole derivative of calix[4]arene. Pyrazole derivatives were the most reactive ones in the reaction with hydrazine hydrate among the studied isostructural calixarenes containing an active α-arylmethyleneoxy moiety. Results of performed quantum chemical calculations allowed us to propose a scheme for the reductive cleavage of oxymethylene derivatives of pyrazole with hydrazine hydrate. [ABSTRACT FROM AUTHOR]

The first total synthesis of anti-inflammatory cyclic peptide fanlizhicyclopeptide B based on the Mitsunobu reaction is reported. The pre-made Fmoc-Tyr-OAllyl building block was coupled to the Wang resin via the Mitsunobu reaction catalyzed by triphenylphosphine and diethyl azodicarboxylate. After the remaining amino acids were assembled, macrocyclization was realized on solid support. Finally, the crude product was cleaved from resin and then purified by preparative reverse-phase high-performance liquid chromatography (RP-HPLC) to provide the pure target fanlizhicyclopeptide B. [ABSTRACT FROM AUTHOR]

A synthesis of novel fluorescent 2-azolyl-6-piperidinylpurine derivatives was designed. Azolyl substituent at purine C-2 atom was introduced via nucleophilic aromatic substitution or in the case of tetrazolyl and 1,2,3-triazolyl substituents via a ring formation on a preinstalled amine or azide moiety, respectively. The obtained purine intermediates were functionalized at N-9 position using Mitsunobu reaction conditions to achieve amorphous compounds, which form thin-layer films of good quality. The synthesized push-pull systems exhibited fluorescence with emission in range of 360–400 nm and quantum yields up to 66% in CH2Cl2 solution and up to 45% in the thin-layer film. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of the neurokinin 1 receptor antagonist (+)-L-733,060 has been achieved using Jacobsen's hydrolytic kinetic resolution strategy. Intermediate tert-butyl (2S,3S)-3-hydroxy-2-phenylpiperidine-1-carboxylate has been synthesized with an overall yield of 10.25% and more than 98% ee via sequential reactions starting from cinnamyl alcohol and using Grubbs metathesis in the final stage. [ABSTRACT FROM AUTHOR]

A directed synthesis of two progesterone metabolites, allopregnanolone and 3a-hydroxy-pregn-4-en-20-one, from Δ16-pregnanolone and progesterone, respectively, was carried out by a reduction of the carbonyl groups in positions 3 and subsequent inversion of the configuration of the resulting alcohols by the Mitsunobu reaction. The selectivity of the reduction of the conjugated carbonyl group in position 3 of progesterone with sodium borohydride in the presence of cerium(III) chloride (Luche reduction) was demonstrated. The ef ect of the obtained metabolites on the proliferation of breast cancer cells of the MCF-7 and T47D lines under normal and steroid-free conditions was studied. It is shown that the ef ect of these compounds on the proliferation depends on the presence of additional steroids in the culture medium. Metabolites exerted small cytostatic ef ects on the growth of the MCF-7 cells under standard conditions, while the transfer of the cells to a steroid-free medium weakened these cytotoxic ef ects. In the experiments with the T47D line cells, the cell growth was stimulated under both standard and steroid-free conditions. Allopregnanolone and progesterone stimulate the growth to a greater extent under steroid-free conditions than under standard ones. [ABSTRACT FROM AUTHOR]

For over half a century, thousands of tons of triphenylphosphine oxide Ph3P(O) have been produced every year from the chemical industries as a useless chemical waste. Here we disclose efficient transformations of Ph3P(O) with cheap resource-abundant metallic sodium finely dispersed in paraffin oil. Ph3P(O) can be easily and selectively transformed to three reactive organophosphorus intermediates—sodium diphenylphosphinite, sodium 5H-benzo[b]phosphindol-5-olate and sodium benzo[b]phosphindol-5-ide—that efficiently give the corresponding functional organophosphorus compounds in good yields. These functional organophosphorus compounds are difficult to prepare but highly industrially useful compounds. This may allow Ph3P(O) to be used as a precious starting material for highly valuable phosphorus compounds. As a byproduct of organic syntheses including the Wittig, Staudinger, and Mitsunobu reactions, triphenylphosphine oxide is often not recycled. Here a transformation of the waste product with metallic sodium to three organophosphorous compounds is presented. [ABSTRACT FROM AUTHOR]

The developments around flow processing technology have paved the way for new avenues and perspectives to consider in the field of organic chemistry and engineering. In this study, customized flow equipment was utilized to develop and optimize the Mitsunobu reaction. The flow reactor was a prototype of a simple tubular reactor based on the plug flow reactor concept. The experimentation methodology was designed through the statistical design of experiments approach to minimize the number of experiments. The molar ratios of cyclohexanol (1) and o-cresol (2) and interaction effects of triphenylphosphine, diisopropyl azodicarboxylate were studied in detail. The reaction profile of flow experiments agreed with the batch conditions adding noteworthy improvements to the overall reaction time, selectivity, and yield towards the desired product 1-(cyclohexyloxy)-2-methylbenzene (3). The Mitsunobu reaction in batch condition would take on an average of 3 to 5 h, which was effectively accomplished in 30 to 45 mins in this flow reactor. The generated mathematical model is in good agreement with the reaction conditions. We believe that the process could be executed continuously without a break, readily scaled to kilogram quantities in a short time without further development. [ABSTRACT FROM AUTHOR]

Well-defined side-chain ferrocene-containing polymers have been synthesized by post-modification of well-defined polyacrylonitrile (PAN). PAN prepared by Cu(0)-mediated single-electron transfer living radical polymerization was further modified using sodium azide and ammonium chloride (NH4Cl) to yield polymeric materials with vinyltetrazole units. Side-chain ferrocene-containing polymer was prepared by vinyltetrazole units and hydroxymethylferrocene after Mitsunobu reaction. FTIR, 1H NMR, UV–Vis spectroscopy and thermogravimetric analysis were used to identify the structure of the target product. After linked the ferrocene unit, the final polymer showed typical redox property with a more negative redox potential (E1/2). [ABSTRACT FROM AUTHOR]

Composition of aminolysis products of phenyl glycidyl ether with benzylamine in various conditions was studied. The ratio of 1-(benzylamino)-3-phenoxypropan-2-ol and 1,1'-(benzylazanediyl)bis(3-phenoxypropan-2-ol) does not considerably depend on the nature of the solvent and is basically determined by ratio of initial reagents. 2,6-Bis(phenoxymethyl)morpholine was obtained by dehydration of aminodiol in conditions of Mitsunobu reaction with subsequent reductive debenzylation. [ABSTRACT FROM AUTHOR]

A simple and efficient synthesis of macrocyclic dilactone tetrahydropyrenophorol has been accomplished from inexpensive and commercially available starting materials. This concise synthesis utilizes regioselective ring opening of epoxide, asymmetric dihydroxylation, and Mitsunobu reaction for the construction of the macrolactone. Graphical abstract: [ABSTRACT FROM AUTHOR]

A new class of 3α-ester derivatives of pregnenolone, using Mitsunobu reaction conditions, is described. The scheme involved the conversion of pregnenolone ( 4) into 20-(2-hydroxyethyl)imino-pregn-5-en-3β-ol ( 8), followed by tritylation to give the analogue 9. Treatment of 9 with various aryl carboxylic acids afforded the tritylated 3α-ester pregnenolone analogues 18-23. Detritylation with AcOH furnished the 3α-substituted aryl ester derivatives 24-29. Analogously, the 3β-ester analogues 31 and 32 were synthesized from pregnenolone ( 4) and its analogue 30, using Steglich coupling method, by treatment with rhodamine B in the presence of DCC/DMAP. These derivatives were screened for their CYP17α hydroxylase inhibition activity expressed in Escherichia coli. Compound 27 was the most active inhibitor among both series, with IC value of 1.12 μM and selectivity profile of 88.56 % inhibition of CYP17α hydroxylase enzyme. [ABSTRACT FROM AUTHOR]

Lower-rim substituted bis- and tetrakis(alkynyloxy)thiacalix[4]arenes in cone and 1,3-alternate configurations were synthesized by the Mitsunobu reaction, and their structure was determined using homoand heteronuclear one- and two-dimensional NMR techniques. Bis(prop-2-yn-1-yloxy)thiacalix[4]arene was found to exist in conformational equilibrium whose position depends on the temperature and reaction conditions. [ABSTRACT FROM AUTHOR]

tert-Butyl 3-allyl-4-oxopiperidine-1-carboxylate and its derivatives substituted at the 3-position and in the allylic fragment reacted with L-selectride in anhydrous tetrahydrofuran to give tert-butyl (3 R,4 S)-3-allyl-4-hydroxypiperidine-1-carboxylates ( cis isomers) in quantitative yield. The Mitsunobu reaction of the latter with formic or benzoic acid, followed by alkaline hydrolysis, afforded the corresponding trans (3 R,4 R) isomers. [ABSTRACT FROM AUTHOR]

The Mitsunobu reaction between 4-diethoxyphosphoryl-2-hydroxymethyl-2-methyl-2,5-dihydrofurane and 6-chloropurine yielded 2-(6-chloropurin-9-ylmethyl)-4-diethoxyphosphoryl-2-methyl-2,5-dihydrofuran, which further reacted with sodium azide to afford 6-azidopurine derivatives. Reduction of the azido group resulted in the corresponding 6-aminopurine derivative, while under catalytic hydrogenation conditions both reduction of the azido group and hydrogenation of the dihydrofuran double bond occurred. [ABSTRACT FROM AUTHOR]

Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via N-tert-butoxycarbonylation. The bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu reaction. Then, a new practical and efficient method is established for the synthesis of penciclovir (PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5-the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional process. The coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions. [ABSTRACT FROM AUTHOR]

The article discusses a synthesis of N-methoxypyrrolidinone 1. The key step of the process is transforming lactone 4 into N-OMe lactam 7, which was elaborated to the target compound 1 in a straightforward three-step sequence. A Shimadzu IR Prestige21 Fourier transform infrared (FTIR) spectrometer was used to record infrared spectra in thin films. An OptimMelt automated melting point system was used to determine the melting points.

The structure-activity relationship of a new series of tetracyclic spirooxindoles led to the discovery of compound 25a, a potent hNa1.7 blocker with improved ADME properties and in vivo efficacy in the CFA-induced inflammatory pain model. [ABSTRACT FROM AUTHOR]

New optically active ionic liquids based on (+)-3-carene and 1H-imidazole were synthesized. Their structures were established. [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of N-Cbz-β-aminoalkanesulfonamides was described. N-Cbz-β-aminoalkanesulfona-mides were readily prepared in good yields from a variety of amino alcohols, including optically active ones, via N-Cbz protection with benzyl chloroformate, Mitsunobu esterification reaction with thiolacetic acid, N-chlorosuccinimide oxidation, and ammonolysis process. [ABSTRACT FROM AUTHOR]

New data, mostly published in the last five years, on methods for the synthesis of N-alkylated indoles both as a result of direct introduction of the alkyl substituent at the nitrogen atom and by construction of the indole heterocyclic system are reviewed. Only examples of indole derivatives containing branched, sterically hindered, and chiral alkyl substituents at the nitrogen atom are discussed. [ABSTRACT FROM AUTHOR]

The cyclization of N-Boc-α-alkylserines to corresponding β-lactones under Mitsunobu reaction conditions and the ring opening with heterocyclic amines (pyrrolidine, piperidine, morpholine and thiomorpholine) produced N-Boc-α-alkyl-β-( sec-amino)alanines. The removal of the Boc group gives di-hydrochlorides of non-protein amino acids. [ABSTRACT FROM AUTHOR]

(5S)-1-benzyl-5-(1H-imidazol-1-ylmethyl)-2-pyrrolidinone and its closely related analog was synthesized from (S)-pyroglutaminol and imidazole or substituted imidazole using Mitsunobu reaction as the key step. Graphical abstract: (i) PhCHO, NaOH, NaBH; (ii) HO, Heat, 15 h; (iii) MeOH/H, NaBH, THF; and (iv) DEAD, PhP, imidazole or 2-methyl imidazole [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Four side-chain maleimide-styrene polymers have been synthesized from maleimide- alt-styrene copolymer (MASt) and some original azo-moieties using polymer analogous reactions. The structures have been obtained with good yields; remarkably, they showed a high chromophore load, up to ~100%. The polymers were characterized by means of SEC, FT-IR, H-NMR, DSC-TGA, and elemental analysis. The side-chain polymers exhibited improved solubility and enhanced thermal stability up to 320ºC, while their glass transition temperatures have been found to be as high as 210ºC. The third-order NLO refraction (n) and susceptibility χ coefficients were measured by Z-scan technique. The results of Z-scan measurements showed that the polymers have only nonlinear refraction, the nonlinear absorption being negligible. [ABSTRACT FROM AUTHOR]

The Mitsunobu reaction is a well-established fundamental reaction and has been widely applied in organic synthesis. In this paper, under Mitsunobu conditions dehydration proceeds between (2-chloroquinolin-3-yl)methanol and nitrogen heterocyclic compounds such as quinazolinone, pyrimidone, 2-oxoquinoline in dry THF in the presence of triethylamine, triphenylphosphane and diethyl azodicarboxylate to give the corresponding products. As part of our recent research, we attempted to couple two N-heterocyclic compounds under Mitsunobu reaction conditions to provide efficient building blocks for natural product synthesis. [ABSTRACT FROM AUTHOR]

An efficient and practical asymmetric synthesis of erythro-(1 R,2 S)-8- O-4′-neolignan myrislignan was achieved by using vanillin and pyrogallic acid as the starting materials. Two key steps are involved: preparation of an enantiopure threo alcohol of predictable stereochemistry by dihydroxylation with AD-mix-β, and inversion of the absolute configuration from the threo to the erythro isomer using a Mitsunobu reaction. The route illustrates a new methodology for the synthesis of erythro-8- O-4′-neolignan. Graphical abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

very short convergent synthesis of dihydrobenzoxazepinones, bearing four diverse diversity points, based on coupling the Ugi reaction with a Mitsunobu cyclization, was developed. These compounds are potential α-helix mimics, where three of the four appendages are expected to imitate the residues in i, i + 4 and i + 7 positions. A library of 22 compounds bearing lipophilic substituents, designed to interact with the hydrophobic cleft of anti-apoptotic protein Bcl-xL, was synthesized. Preliminary biochemical tests, based on competitive binding, have already been carried out. [ABSTRACT FROM AUTHOR]

simple method for the preparation of a biologically active analog of bacterial undecaprenyl phosphate bearing the phenoxy group at the ω-end of the chain was developed on the basis of accessible polyprenols from mulberry ( Morus nigra) leaves. It includes the selective van Tamelen epoxidation of the ω-terminal isoprene unit of polyprenyl acetates, conversion of the epoxides into ω-terminal aldehydes, their hydride reduction into hydroxy acetates followed by the Mitsunobu condensation with phenol, and phosphorylation of the resulting phenoxy alcohols. The biological activity of the obtained phosphates was tested by the radiometry method in the initiation of O-antigenic polysaccharide assembly reaction using the cell membrane preparations from the Gram-negative bacteria Salmonella arizona O:59 and Aeromonas hydrophila AH-1. [ABSTRACT FROM AUTHOR]

The N-alkylation of 2- and 3-phenylsulfonylindoles under various conditions and the subsequent removal of the activating phenylsulfonyl group by reductive desulfonylation using Raney nickel leads to N-alkylindoles in high yield. 2-Phenylsulfonylindole readily undergoes the Mitsunobu reaction, while isomeric 3-phenylsulfonylindole is relatively inert under these conditions. [ABSTRACT FROM AUTHOR]

The article focuses on a study related to the synthesis of triazoles and its reactions with electrophilic agents. Topics discussed include usage of these compounds for biological and medicinal chemistry, reactions of nitroalkene with sodium azide, usage of Mitsunobu reaction, electronic properties of reactants, designing of other triazole derivatives and ratio of reaction product on the nature of the reaction conditions.

Methods for the design of nitrogen-containing heterocyclic systems involving the formation of C-N bonds under the conditions of the Mitsunobu reaction are discussed. [ABSTRACT FROM AUTHOR]

A simple method is proposed for the synthesis of optically active indole-2-carbaldehydes via alkylation of 2-cyanoindole by optically active secondary alcohols and subsequent reduction of the cyano group to an aldehyde. Reaction of the aldehydes obtained with aromatic amines gave imines whose reaction with the Danishefsky diene was studied. The structure of the major diastereomer of (2R′)-1-phenyl-2-[1-((1R′)-1-phenylethyl)indol-2-yl]-1,2,3,4-tetrahydropyridine-4-one and minor diastereomer (2S)-2-[1-((1S)-2-methoxy-1-phenylethyl)indol-2-yl]-1-phenyl-1,2,3,4-tetrahydropyridine-4-one respectively were established by X-ray analysis. [ABSTRACT FROM AUTHOR]

A convenient route to amino acid-based orthogonally protected 1,2-diamines starting from materials readily available for a peptide chemist is presented. The key step of the procedure is the Mitsunobu reaction of N-protected aminoalcohol, obtained by the reduction of commercially available Z- or Boc-protected amino acid, with imidodicarbonate or sulfonylcarbamate related to standard amino-protecting groups used in peptide chemistry yielding triprotected vicinal diamines. [ABSTRACT FROM AUTHOR]

A study of the Mitsunobu reaction involving calix[4]arene and a series of benzylic and allylic alcohols reveals the structural effect of the alcohol component on the distribution between Oand C-alkylation of the phenol component in the formation of aryl alkyl ethers and p-alkylated phenols, respectively. [ABSTRACT FROM AUTHOR]

A method has been developed for the synthesis of isosteric analogs of nicotine involving ethers of S(-)-1-2-pyrrolidinemethanol and S(-)-1-2-pyrrolidineethanol based on the Mitsunobu reaction. The results of testing the synthesized compounds as calcium channel blockers are presented. [ABSTRACT FROM AUTHOR]

One of the initial steps in the development of therapeutic agents is the identification of lead compounds that bind to the target of interest. Use of combinatorial libraries allows the screening of thousands to millions of compounds. To optimize the characteristics of the first generation of compounds, many of their analogues need to be synthesized. In this sense, 5-hydroxytryptophan closely resembles tryptophan. Both, however, are sensitive to oxidation and alkylation during solid-phase peptide synthesis. In an effort to overcome these side reactions during oligopeptide synthesis, we prepared N-Fmoc- N-Boc-5- O-benzyl-5-hydroxytryptophan. To evaluate its properties, this building block was incorporated in a pentagastrin analogue using Fmoc/ tBu chemistry. After deprotection and cleavage from the support, the products were purified and identified. The fully deprotected peptide was the main compound, contaminated by its 5- O-benzylated analogue. The relative amount of the latter decreased using longer deprotection times. [ABSTRACT FROM AUTHOR]

Starting from L-tyrosine ( L- 1), the phenyl lactic acid ester (−)- 4 was prepared by reported procedures. (−)- 4 could then be converted to the benzyl ether (−)- 5. From (−)- 5, the corresponding optical antipode (+)- 5 is available via (+)- 6 by Mitsunobu reaction. The en-antiomeric excess of 5 was determined by NMR spectroscopy from camphanic acid esters (+)- and (−)- 8, respectively. The phenyl lactic acid esters (+)- and (−)- 5 were acylated by caffeoyl chloride ( 9) to yield the O-protected enantiomeric rosmarinic acid esters (+)- and (−)- 10. Deprotection of 10 by BCl3 afforded the title compounds (+)- and (−)- 11 in fair yields. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Monthly / Monatshefte für Chemie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Monthly / Monatshefte für Chemie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stereoselective synthesis of anti-2-aryl-4-en-1-ols from the corresponding syn isomers was accomplished with 71-83% yields via the Mitsunobu reaction. [ABSTRACT FROM AUTHOR]

As one of the most important precursors, polyacrylonitrile (PAN) and its functionality gained extensive attention but faced challenges in the preparation of nanofiber by electrospinning technology. Herein, poly(acrylonitrile-g-ethylene alcohol) (PAN-g-PEG) were succussfuly synthesized by the modification of PAN, using the methods of Click Chemistry and Mitsunobu reaction sequentially. Firstly, well-defined PAN was prepared by Cu(0)-mediated controlled/living radical polymerization with a molar ratio of [AN]0:[EBiB]0:[Cu]0:[TEMED]0 = 500:1:1:2. Tetrazole-containing PAN was then successfully modified by nitrile-Click Chemistry, which sodium azide and ammonium chloride was used as substrate and catalyst, respectively. Using Mitsunobu reaction, PAN-g-PEG was obtained from tetrazole-containing PAN and poly(ethyl alcohol) with the catalyst of diethyl azodicarboxylate and triphenylphosphine. After typical characterization, PAN-g-PEG nanofiber with the average diameter around 90 nm, was successfully prepared by electrospinning. The obtained PAN-g-PEG nanofiber has a smoother surface than PAN nanofiber, which suggests that a new modification approach of PAN nanofiber is successfully achieved. [ABSTRACT FROM AUTHOR]

The article discusses the Mitsunobu reaction and the separation of hydrazine dicarboxylate and phosphine oxide from the desired reaction products. It explores the study by Tsuyoshi Taniguchi and colleagues from Kanazawa University in Japan, which created conditions which the hydrazine component can be recycled into catalyst. It suggests that an inversion of stereochemistry in the chiral alcohol reaction indicates the occurrence of Mitsunobu-type mechanism.