Furanone Ring Research Articles

The Structure of“Organic Permanganate”

Not a diphenylketene dimer, as has long been presumed, but the p-quinodimethane derivative 1 is formed (inter alia) upon pyrolysis of benzilic acid. In contrast to the related orange-yellow 2 (“Thiele's hydrocarbon”), 1 is deep black-red; this can be attributed to expansion of the conjugated system by the condensed furanone ring.

Constituents of Eupomatia Species. xiv. The Structures of Eupomatilone-1, -2, -3, -4, -5, -6 and -7 Isolated From Eupomatia Bennettii

On the basis of spectroscopic evidence, the eupomatilones (from eupomatilone-1 to -7) isolated from Eupomatia bennettii F. Muell. were shown to be degraded lignans . Eupomatilone-1 was assigned the structure (1), cis-4-methyl-3-methylene-5-(3″,4″,5″,6′-tetramethoxy-4′,5′-methylenedioxybiphenyl-2′-yl)dihydrofuran-2(3H)-one. The other six eupomatilones differ from eupomatilone-1 either in the degree of oxygenation of the biphenyl system or in the substitution of the furanone ring. Atropisomerism was observed with the compounds.

A [3+2] nitrile oxide intermolecular cycloaddition approach to 4,5-dihydro-3(2H)-furanone and 3(2H)-furanone ring systems: application to the formal synthesis of (±)-ascofuranone and geiparvarin.

A unified approach to both 4,5-dihydro-3(2H)-furanone and 3(2H)-furanone rings systems centered on a [3+2] nitrile oxide cycloaddition strategy as a tool for the crucial carbon-carbon bond forming step has been successfully applied to the formal synthesis of )(±)-ascofuranone and to a new synthesis of geiparvarin from common intermediates.

Isoxazoles-mediated synthesis of geiparvarin and dihydrogeiparvarin

A new synthesis of geiparvarin 1 and its dihydroderivative 2 two naturally occurring antitumor agents, possessing the 3(2H)-furanone ring system central structural feature, is described. The synthetic design is based on the use of suitably substituted isoxazole derivatives, the heterocyclic ring acting as masked 1,3-diketone moiety.

Reduction of Δ 2-isoxazolines-2. A facile synthesis of 3(2H)-furanones.

A simple synthesis of the 3(2H)-furanone ring system is described.

Sesquiterpene lactones from Eremanthus species

The investigation of three Eremanthus species afforded, in addition to known compounds, several new sesquiterpenelactones, a cumambrin B isobutyrate, four lactones related to the eremantholides, two to zexbrevin and one to goyazensolide. Furthermore, a new coniferyl alcohol derivative was isolated. The overall picture of the genus is very uniform. The occurrence of eremanthine and germacranolides with a furanone ring seems to be especially typical.

Synthesis of geiparvarin: a novel antitumor agent possessing a 3(2H)-furanone ring

The first synthesis of geiparvarin as well as assignment of configuration of the previously undefined trisubstituted olefinic bond has been achieved.

ChemInform Abstract: CONJUGATED ADDITION TO 2,2‐DIMETHYL‐3(2H)‐FURANONE‐ SUPPORT FOR THE BALDWIN RULES FOR RING CLOSURE

AbstractDas Dimethylfuranon (I) liefert mit 2,5 Equival.

X-Ray crystal and molecular structure of a dispirothiiran: 1,1,3,3,7,7,9,9-octamethyl-2,8-dioxa-11-thiadispiro[4.0.4.1]undecane-4,10-dione

X-Ray analysis of the title compound shows the molecule to have two furanone rings spiro-fused to a thiiran ring; during the X-ray exposure, small crystal platelets grew on the parent crystal, and these are of a new compound, as yet uncharacterized.

Conjugated Addition to 2,2-Dimethyl-3(2h)-furanone: Support for the Baldwin Rules for Ring Closure

Abstract In connection with our exploratory studies directed at devising a total synthetic approach to jatro-phone1 and related antitumor agents,2 we have recently explored conjugate addition of organocuprates3 to the 3 (2H)-furanone ring system. In this letter we document the results of that study.

Crystal and molecular structure of 2?,2?,4,4,5?,5?,6,6-octamethyl-2?,4,5?,6-tetrahydrofuro[3,4-d]-1, 3-oxathiol-2-spiro-3?-furan-4?-(3?H)-one

Crystals of the title compound are monoclinic,a = 13.966(4),b = 9.141(3),c= 15.901(6) A, β=123.0(7) °,Z = 4. The structure was established by direct methods based on 2827 reflections, using MoKα radiation, refined to an ultimate coventionalR of 0.081. The furanone ring is closely similar to that found in a related spiro-connected molecule in this series.