Butenolide Derivatives Research Articles

Facile Synthesis of β‐Organotellurobutenolides via Electrophilic Tellurolactonization of α‐Allenoic Acids.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Acid‐Mediated Highly Regioselective Oxidation of Substituted Furans: A Simple and Direct Entry to Substituted Butenolides.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Facile Synthesis of β-Organotellurobutenolides via Electrophilic Tellurolactonization of α-Allenoic Acids

We report a convenient and highly efficient method for the synthesis of beta-organotellurobutenolides by the aryltellurenyl halides-induced electrophilic tellurolactonization of alpha-allenoic acids under mild conditions. The resulting beta-organotellurobutenolides can be utilized as precursors for versatile butenolide derivatives through a substitution reaction with organocuprate reagent or Pd/Cu(I)-catalyzed cross-coupling with terminal alkyne.

Design, Synthesis, and Biological Evaluation of a Series of β-Lactam-Based Prodrugs

By use of pro-dual-drug concept the synthesis of 6-β-[( R)-2-(clavaminio-9- N-yl)-2-(4-hydroxyphenylacetamido)]penicillanic acid ( 10), 6-β-[( R)-2-(amino)-2-(4-(clavulano-9- O-yl)phenylacetamido)]penicillanic acid ( 13), ( Z)-4-[2-(amoxycillin-4- O-yl)ethylidene]-2-(clavulano-9- O-yl)-3-methoxy-Δ α,β-butenolide ( 19), and 3-[(amoxicillin-4- O-yl)methyl]-7-(phenoxyacetamido)-(1-oxo)-3-cephem-4-carboxylic acid ( 23) was accomplished. Unlike penicillin G, ampicillin, or amoxicillin, these four heretofore undescribed compounds 10, 13, 19, and 23 showed notable activity against β-lactamase (βL) producing microorganisms, Staphylococcus aureus A9606, S. aureus A15091, S. aureus A20309, S. aureus 95, Escherichia coli A9675, E. coli A21223, E. coli 27C7, Pseudomonas aeruginosa 18S-H, and Klebsiella pneumoniae A20634 TEM. In comparison with amoxicillin ( 9), α-amino-substituted compound 10 and butenolide derivative 19 showed a broadened spectrum of antibacterial activity; yet they were found to be less active than 13 and 23. Like clavulanic acid ( 7) or cephalosporin-1-oxide ( 21), the newly synthesized compounds 10, 13, 15, 16, 19, or 23 functioned as potent inhibitors of various bacterial βLs.

Oxidative Cyclization-Dimerization Reaction of 2,3-Allenoic Acids and 1,2-Allenyl Ketones: An Efficient Synthesis of 4-(3′-Furanyl)butenolide Derivatives

The active PdII catalyst in the efficient oxidative cyclization/dimerization reaction between 2,3-allenoic acids 1 and 1,2-allenyl ketones 2 to give 4-(3′-furanyl)butenolide derivatives 3 may be regenerated from Pd0 after a cyclometalation/protonolysis step in the catalytic cycle.

Palladium(0)-catalyzed coupling-cyclization reaction of polymer-supported aryl iodides with 1,2-allenyl carboxylic acids. Solid-phase parallel synthesis of butenolides.

In this contribution, we constructed a library of butenolides with 77 members by parallel synthesis strategy on Merrifield resin. Sixteen 2,3-allenoic acids and 12 polymer-bound aryl iodides were combined to react with each other, and then the polymer-supported products were cleaved to release butenolide derivatives. The reactions with alkyl-substituted 2,3-allenoic acids in acetonitrile afforded the corresponding products in high yields and high purities, whereas those with aryl-substituted acids in acetonitrile failed. After some reaction conditions were screened, the solid-phase reactions with aryl-substituted 2,3-allenoic acids were realized in toluene, and the products are of good purities albeit in slightly low yields. In the benzyl ether linkage, a new cleavage model was found. By adding 6 equiv of acetyl bromide, we can get single (5-oxo-2,5-dihydrofuran-3-yl)benzyl bromide other than the corresponding benzyl acetate. To further increase the diversities, a dihydropyran (DHP) linker was introduced into our combinatorial synthesis of butenolides. By reversing the addition sequence of 2,3-allenoic acids and organic base, we realized the solid-phase cyclization reaction of polymer-bound aryl iodides with the THP linkage in moderate yields and good purities. Now the library of butenolides includes (5-oxo-2,5-dihydrofuran-3-yl)benzoic acids, -aryl acetates, -benzyl bromides, -benzyl alcohols, and -phenols, which are difficult to synthesize with conventional solution methods.

ChemInform Abstract: Total Synthesis of an Anticancer Agent, Mucocin. Part 2. A Novel Approach to a γ‐Hydroxy Butenolide Derivative and Completion of Total Synthesis.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Total synthesis of an anticancer agent, mucocin. 2. A novel approach to a γ-hydroxy butenolide derivative and completion of total synthesis

Total synthesis of mucocin ( 1) was accomplished through a palladium-catalyzed cross coupling reaction of the C 10C 34 fragment of 1 and a newly designed γ-hydroxy butenolide subunit, which was synthesized by taking advantage of radical cyclization of an acyclic olefin having a selenocarbonate group derived from L-rhamnose.

ChemInform Abstract: Asymmetric Synthesis of Butenolide and Butyrolactone Derivatives.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Asymmetric synthesis of butenolide and butyrolactone derivatives

2-Trimethylsiloxyfuran and 4-methoxy-2-trimethylsiloxyfuran, which are readily prepared from butenolide and methyl tetronate respectively, have been reacted with a series of homochiral ortho-esters and oxazolidine derivatives in the presence of Lewis acids to afford homochiral 2(5 H)-furanone derivatives. The structures of these products have been determined using nmr spectroscopy and, where possible, by X-ray analysis. Preliminary experiments have been carried out involving conjugate addition to these unsaturated lactones, demonstrating their potential as substrates for natural product synthesis.

Ruthenium(II) catalysed rearrangement of the natural cyclic peroxide G3; X-ray crystallographic structure determination of a butenolide derivative

The natural cyclic peroxide G3 is rearranged in the presence of a RuII–tertiary phosphine complex, to an ene pentadione and to a bicyclic hemiacetal butenolide; the structures have been respectively assigned by CPG–MS analysis and X-ray studies.

Synthesis and evaluation of cardiotonic activity of simple butenolides

Simple butenolide derivatives have been synthesized and their properties have been tested as inotropic agents. Although these compounds maintain the butenolide and the 14-hydroxyl group as compared with natural cardenolides, they lack inotropic activity.

糖類の選択的分解反応 有用合成中間体の短段階合成への応用

Control of degradation reactions of carbohydrates and their applications to short-step syntheses of useful synthetic intermediates by using D-glucono-1, 5-lactone, D-glucopyranuronic acid, and D-glucofuranurono-6, 3-lactone as starting materials are described.The conversion of carbohydrate derivatives to useful synthetic intermediates is successfully achieved by alcoholysis of the degradation products obtained under acetylation conditions.Under acetylation conditions, mono-unsaturated derivatives of D-glucono-1, 5-lactone and D-glucopyranuronic acid, α-pyrone derivatives, butenolide derivatives, a sorbic acid derivative, comanic acid, etc. are obtained from D-glucono-1, 5-lactone, tetraacetate of D-glucopyranuronic acid, and triacetate of D-glucofuranurono-6, 3-lactone in high yields.4, 5-Mono-unsaturated derivative of D-glucopyranuronic acid and α-pyrone derivatives are selectively converted to cyclopentenone derivatives under alcoholysis conditions in the presence of base. On the other hand, 2, 3-mono-unsaturated derivative of D-glucono-1, 5-lactone affords furan derivative under alcoholysis conditions using acid as catalyst.Further, 4-hydroky-4-methoxycarbonyl-2-cyclopentenone, prepared from D-glucono-1, 5-lactone via α-pyrone derivative, is successfully degraded to afford a valuable synthetic intermediate, 1, 3-cyclopentanedione.

Radical copolymerization of γ‐methylene‐Δα,β‐butenolide derivative: ethyl(E)‐5‐OXO‐2,5‐dihydrofuran‐2‐ylidene‐acetate

AbstractRadical polymerications including co‐ and terpolymerizations of a γ‐methylene‐Δα,β‐butenolide derivative, ethyl (E)‐5‐oxo‐2,5‐dihydrofuran‐2‐ylideneacetate(EODY) was investigated. The monomer had no homopolymerizability but copolymerized with styrene (ST) and 1,3‐cyclohexadiene to yield alternating copolymers. From IR and 1H‐NMR spectra of the copolymers, the 1,4‐addition was confirmed to exclusively occur for the conjugated double bond of EODY. Terpolymerization for the system involving an acceptor monomer such as maleic anhydride, α‐chloromaleic anhydride, or 7,7,8,8‐tetracyanoquinodimethane in addition to ST and EODY gave the terpolymer containing about 50 mol% of ST, in spite of a high fraction of ST in the feed. It was inferred that such an apparent behavior of EODY as an acceptor monomer could be due to a resonance‐stabilization of the propagating radical having EODY as a terminal unit, which is also responsible for the poor yields of the copolymers and terpolymers.

Radical copolymerization of γ‐methylene‐Δα,β‐butenolide derivative: Ethyl(E)‐5‐oxo‐2,5‐dihydrofuran‐2‐ylidene‐acetate

AbstractRadical polymerications including co‐ and terpolymerizations of a γ‐methylene‐Δα,β‐butenolide derivative, ethyl (E)‐5‐oxo‐2,5‐dihydrofuran‐2‐ylideneacetate(EODY) was investigated. The monomer had no homopolymerizability but copolymerized with styrene (ST) and 1,3‐cyclohexadiene to yield alternating copolymers. From IR and 1H‐NMR spectra of the copolymers, the 1,4‐addition was confirmed to exclusively occur for the conjugated double bond of EODY. Terpolymerization for the system involving an acceptor monomer such as maleic anhydride, α‐chloromaleic anhydride, or 7,7,8,8‐tetracyanoquinodimethane in addition to ST and EODY gave the terpolymer containing about 50 mol% of ST, in spite of a high fraction of ST in the feed. It was inferred that such an apparent behavior of EODY as an acceptor monomer could be due to a resonance‐stabilization of the propagating radical having EODY as a terminal unit, which is also responsible for the poor yields of the copolymers and terpolymers.

Selective inhibition of separated forms of cyclic nucleotide phosphodiesterase from rat heart by some cardio- or vaso-active butenolide derivatives

Some butenolide derivatives which exhibit pharmacological actions on the cardiovascular system proved to be efficient inhibitors of cardiac cyclic nucleotide phosphodiesterase. Rat heart myocardial enzyme was separated into several distinct forms: three main cytolic species, isolated by isoelectric focusing and one particulate form, prepared as a washed 105,000 g pellet. Butenolidic compounds selectively inhibited a cytosolic form of pI 5.45, which hydrolyses more efficiently cyclic GMP than cyclic AMP at low substrate concentrations, but is preponderant for the hydrolysis of both substrates when they are present at higher concentrations.

2,3-DIMETHYL-4-METHOXYBUTENOLIDES FROM RED ALGAE, COELOSEIRA PACIFICA AND AHNFELTIA PARADOXA

Abstract Three new butenolide derivatives were isolated from the red algae, C. pacifica and A. paradoxa. The structures of these compounds were determined from their spectral properties, one of which was confirmed by synthesis.

Cyclization of polyenes: VI. Biogenetic-type synthesis of levantenolides isolated from Turkish tobacco

Keto acid (VII) was assumed to be a precursor in the biogenesis of levantenolides (IV and V). The syntheses of the analogous compounds (IX and X) and their cyclization to IV and V were carried out as follows. Reaction of farnesyl bromide (XV and XX) with 2,2′-di-3-methylfurylmercury afforded the corresponding furano derivatives (XVI and XXI), which were photo-oxidized to butenolide derivatives (IX and X). Biogenetic-type cyclization of IX and X with stannic chloride afforded IV, V, and XIX in moderate yields.

Intramolecular reactions of nitro-olefin–cyclohexane-1,3-dione Michael adducts. Crystal structure of 3-(4-bromophenyl)-6,7-dihydro-2-hydroxyiminobenzofuran-4(5H)-one

Cyclohexane-1,3-dione and its 5,5-dimethyl derivative (dimedone), in contrast to other β-diketones, behave abnormally in Michael additions to nitro-olefins. From nitro-olefins RCHCH·NO2(R = alkyl or aryl, not H) 3-substituted 6,7-dihydro-2-hydroxyiminobenzofuran-4(5H)-ones can be prepared. These compounds are the first known butenolide derivatives having a 2-hydroxyimino-substituent. 3-(4-Bromophenyl)-6,7-dihydro-2-hydroxyiminobenzofuran-4(5H)-one has been prepared from cyclohexane-1,3-dione and 4-bromo-β-nitrostyrene and resolved into pure syn- and anti-forms. The structures of both forms have been established from n.m.r. spectra, and by X-ray crystallography from diffractometer data. Single crystals of a 1 : 2 mixture of syn- and anti-forms (VIIA and B; anti: syn= 2 : 1) are orthorhombic with space-group Pbca, cell dimensions a= 17·37, b= 7·89, and c= 19·76 Å. The crystals were found to be disordered because they contain a mixture of syn- and anti-forms of the oxime. Three possible ways of describing the mixture of syn- and anti-forms were refined by full-matrix least-squares of 805 statistically significant reflections to weighted R values of 0·051, 0·056, and 0·073. None of the three refinements gave good agreement with bond distances previously reported for CN an N–OH in oxime structures (although mean values for the 0·051 and 0·057 refinements did). The observed apparent planarity of the cyclohexenone ring is attributed to the presence of equal amounts of both ring-inversion isomers in the crystalline state. Short intermolecular distances of 2·63 and 2·84 Å between the oxygen of both syn- and anti-oxime groups and the ketonic oxygens give strong evidence for intermolecular hydrogen bonding.