The title compound, C(6)H(12)O(5), is the α-pyran-ose form of the reducing aldose 2-de-oxy-d-arabino-hexose. The six-membered pyran-ose ring adopts a (4)C(1) conformation, with the anomeric hy-droxy group in axial and the other substituents in equatorial positions. In the crystal, each of the four hy-droxy groups acts as an inter-molecular hydrogen-bond donor function, resulting in a three-dime...

The title compound, C(25)H(21)ClO(2), was synthesized via the three-component coupling of 4-chloro-benzaldehyde, 2-naphthol and 5,5-dimethyl-cyclo-hexane-1,3-dione. The pyran ring adopts a boat conformation, while the cyclo-hexenone ring is in an envelope conformation. The 4-chloro-phenyl ring is almost perpendicular to the pyran ring [dihedral angle = 87.39 (1)°]. In the crystal, mol-ecules ar...

In the title compound, C(14)H(11)BrN(2)O(3)S, the 2,3-dihydro-thio-phene ring is almost planar [maximum deviation = 0.006 (1) Å]. The pyran ring is in an envelope conformation [puckering parameters Q = 0.115 (2) Å, θ = 77.5 (10), ϕ = 172.9 (10)°]. The pyran and phenyl rings are approximately perpendicular, making a dihedral angle of -76.4 (2)°. The crystal packing is stabilized by inter-molecul...

In the title compound, [Fe(C5H5)(C14H10NO3)], the cyclo-penta-dienyl rings are in an eclipsed conformation and the pyran ring adopts a half-chair conformation. The mean plane of the pyran ring makes dihedral angles of 79.33 (1) and 80.73 (1)°, respectively, with the substituted and unsubstituted cyclo-penta-dienyl rings. In the crystal, pairs of C-H⋯O hydrogen bonds link the mol-ecules into inv...

New activated macrophage-specific antigen (AcM.1) detected by a monoclonal antibody has been described. The AcM.1 antigen was only detectable on activated macrophages induced by pyran and Corynebacterium parvum but not on resident or thioglycollate medium (TGC), proteose-peptone, and mineral oil-elicited macrophages, and not on blood monocytes and neutrophils. Activated macrophages induced by p...

PYRAN COPOLYMER, A KNOWN IMMUNOSTIMULATOR, WAS FOUND TO BE A POTENT INHIBITOR OF PURIFIED DNA POLYMERASE (DEOXYNUCLEOSIDETRIPHOSPHATE: DNA deoxynucleotidyltransferase; EC 2.7.7.7) isolated from avian myeloblastosis virus. Unlike other inhibitors, pyran showed unique features of inhibition. It interacts with the polymerase at a region other than the template site. The inhibitory effect was overc...

In the title compound, C20H18O7, the dioxolane ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap, and its mean plane makes a dihedral angle of 73.25 (2)° with the pyran ring mean plane. The furan ring makes dihedral angles of 67.43 (12) and 6.20 (11)° with the mean plane of the dioxolane and pyran rings, respectively. The O atom attached to the pyran ring dev...

Introduction. – The 6-substituted 5,6-dihydro-2H-pyran-2-one A, an a,b-unsaturated d-lactone, is an important structural subunit in many biologically promising natural products. This unit is of interest for a wide variety of biological activities, such as insect-growth inhibitors and insect antifeedent, cytotoxic activities, and antifungal and antitumor properties [1]. The pyran units are widel...

The title compound congestiflorone, C(28)H(32)O(4), which was isolated from the stem bark of Mesua congestiflora, consists of a benzophenone skeleton with two attached pyran rings to which a cyclo-hexane ring and a C6 side chain are bonded. The benzene ring is significantly distorted from planarity (r.m.s. deviation = 0.0007 Å) due to the constraints imposed by junctions with the two pyran ring...

A series of naphthopyran derivatives 3a-f were prepared. Reaction of 2-amino-4-(p-chlorophenyl)-7-methoxy-4H-naphtho[2,1-b]pyran-3-carbonitrile (3b) with Ac2O afforded two products, 2-acetylamino-7-methoxy-4-(p-chlorophenyl)-4H-naphtho-[2,1-b]pyran-3-carbonitrile (4) and 10,11-dihydro-3-methoxy-9-methyl-12-(p-chloro-phenyl)-12H-naphtho[2,1-b]pyran[2,3-d]pyrimidine-11-one (5) and treatment of 3b...