Two Pseudomonas strains known to utilize furan derivatives were shown to respond chemotactically to furfural, 5-hydroxymethylfurfural, furfuryl alcohol, and 2-furoic acid. In addition, a LysR-family regulatory protein known to regulate furan metabolic genes was found to be involved in regulating the chemotactic response.

The title compound, C(12)H(11)N(3)O(2), was prepared by the reaction of isonicotinohydrazide and 5-methyl-furan-2-carbalde-hyde. The pyridine ring makes a dihedral angle of 46.90 (9)° with the mean plane of the furan ring. The crystal packing is stabilized by a bifurcated inter-molecular N-H⋯(N,O) inter-action.

Expression arrays were used to identify 4 putative oxidoreductases that were upregulated (>3-fold) by furfural (15 mM, 15 min). Plasmid expression of one (ucpA) increased furan tolerance in ethanologenic strain LY180 and wild-type strain W. Deleting ucpA decreased furfural tolerance. Although the mechanism remains unknown, the cryptic ucpA gene is now associated with a phenotype: furan resistance.

In the title mol-ecule, C(23)H(20)N(4)O(2)S, the triazole ring forms dihedral angles of 150.3 (2), 77.3 (2) and 77.6 (2)°, respectively, with the furan ring and the phenyl rings. The furan ring is almost perpendicular to the central phenyl ring, making a dihedral angle of 86.0 (3)°.

In the title racemic compound, C(14)H(10)ClNO(3), which contains four stereogenic centres, the cyclo-hexane ring tends towards a boat conformation, while the tetra-hydro-furan and dihydro-furan rings adopt envelope conformations. The dihedral angle between the mean planes of the pyrrolidine-2,5-dione unit and the 4-chloro-phenyl ring is 49.0 (2)°.

The title compound, C(19)H(11)NO, is stabilized by one intra-molecular C-H⋯O hydrogen bond. The compound can be synthesized in good yield (49%), by transformation of functional groups [starting with 5-(fluoren-9-ylidenemeth-yl)furan-2-carbaldehyde]. The flourene and furan ring systems are nearly coplanar, with a dihedral angle of 6.36 (7)°.

The title compound, C(14)H(15)N(3)O(2), was prepared by the reaction of 4-(dimethyl-amino)-benzaldehyde and furan-2-carbohydrazide. The dihedral angle between the benzene ring and the furan ring is 25.59 (19)°. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds, forming chains along [010].

In the title compound, C14H13NO3, the dihedral angles between the central pyrrolidine ring and the pendant tetra-hydro-furan and phenyl rings are 5.34 (18) and 58.99 (17)°, respectively. The tetra-hydro-furan ring is almost planar (r.m.s. deviation = 0.008 Å). In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating a three-dimensional network.

A concise, diastereoselective total synthesis of (±)-cortistatin J has been completed in 20 steps from furan. Key steps include an intramolecular [4 + 3] cyclization of a disubstituted furan with a (Z)-2-(trialkylsilyloxy)-2-enal to construct the tetracyclic core and a (Z)-vinylsilane/iminium ion cyclization to form the A ring.

Similar to acrylamide, furan is a process contaminant which evolves within the production and preparation of food during heat treatment (sterilising, roasting, baking) from natural components of the food. So far, reducing sugars, amino acids, ascorbic acid, unsaturated fatty acids and carotenoids were identified as possible precursors transforming into furan under the influence of heat. The fol...