نتایج جستجو برای: furan
تعداد نتایج: 3475 فیلتر نتایج به سال:
The title compound, C(20)H(30)ClNO(3), was obtained via a tandem asymmetric Michael addition-elimination reaction of (5S)-3,4-dichloro-5-(l-menth-yloxy)-2(5H)-furan-one and diallyl-amine in the presence of potassium fluoride. The mol-ecular structure contains an approximately planar five-membered furan-one ring [maximum atomic deviation = 0.0221 (3) Å] and a six-membered ring adopting a chair c...
The title hydrated salt, C(21)H(17)N(2)O(3) (+)·Cl(-)·H(2)O, exhibits disorder in one of the furan rings. The major and minor components have a refined occupancy ratio of 0.844 (19):0.156 (19). The structure displays intermolecular hydrogen bonding involving the water molecule and the chloride anion. Close intermolecular C-H⋯Cl and C-H⋯(furan ring) inter-actions complete the hydrogen bonding.
A highly efficient method for the construction of 3a,6a-dihydrofuro[2,3-b]furan derivatives has been developed via a novel bicyclization, which is very valuable for the synthesis of fused furofuran compounds since it is time-saving and catalyst-free. Based on the bicyclization, a coupled domino strategy has been developed to directly construct 3a,6a-dihydrofuro[2,3-b]furan derivatives from meth...
The title compound, C15H19NO4, is the a product of the esterification of the corresponding carbonic acid with methanol. The mol-ecule comprises a fused tetra-cyclic system containing three five-membered rings (2-pyrrolidinone, tetra-hydro-furan and di-hydro-furan) and one seven-membered ring (azepane). The five-membered rings have the usual envelope conformations, with the quaternary C atom bei...
Based on evidence from rodent models, it was hypothesized that furan fatty acids found in corn would inhibit reproduction in the laying hen. An isomeric mixture of furan fatty acids [9, (12)-oxy-10,13-dihydroxystearic acid and 10, (13)-oxy-9,12-dihydroxystearic acid] was administered for a period of 3 wk via the diet (1 and 3 ppm) at levels greater than those in corn to 20-wk-old pullets. There...
The structure of traditional, linear phenol-formaldehyde (PF) resins and phenol-furfural (P-Furan) resins has been investigated by matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectroscopy. The structure of a variety of oligomers has been obtained and the structures present in each of the two types of resins related to the reagent used either formaldehyde or furfu...
In the title mol-ecule, C(14)H(12)O(3), the prop-2-en-1-one unit forms dihedral angles of 12.96 (5) and 7.89 (7)° with the 4-meth-oxy-phenyl group and the furan ring, respectively. The furan and benzene rings form a dihedral angle of 8.56 (5)°. In the crystal, C-H⋯π and π-π inter-actions are observed between the benzene and heterocyclic rings [centroid-centroid distance = 3.760 (1) Å].
Two new a,b-unsaturated butyrolactone derivatives, 4-(400-hydroxybenzyl)-3-(30-hydroxy-phenethyl)furan-2(5H)-one (1) and 3-(30-hydroxyphenethyl)furan-2(5H)-one (2), together with one known phenolic compound (3), were isolated from the tubers of Pleione bulbocodioides (Franch.) Rolfe. Their structures were elucidated by analysis of spectroscopic data. # 2007 Wen Yuan Gao. Published by Elsevier B...
A novel metal-free approach to construct the tetrasubstituted furans from Morita-Baylis-Hillman (MBH)-carbonates of acetylenic aldehydes has been developed. This strategy involves the cascade nucleophilic substitution/5-exo-dig-cycloisomerization of MBH-carbonates with 1,3-dicarbonyl compounds to give uniquely substituted 2-furan-3-yl acrylates. Additionally, the obtained furan adducts open a n...
The title compound, C(19)H(30)ClNO(5), was obtained by the tandem asymmetric Michael addition-elimination reaction of (5S)-3,4-dichloro-5-(l-menth-yloxy)furan-2(5H)-one and l-valine in the presence of potassium hydroxide. The furan-one unit is approximately planar (r.m.s. deviation = 0.0204 Å) and the six-membered cyclo-hexane ring adopts a chair conformation. The crystal structure is stabilize...
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