The Front Cover shows 5-bromo-2-(tetrahydro-2H-pyran-4-yl)pyridine – one of many sp3-enriched pyridine derivatives prepared on a multigram scale by group Ukrainian chemists. background photo Anatolii Varenyk depicts the Kilometre Zero Ukraine Sign (also known as “The Winged Globe”) control point located Independence Square (Maidan Nezalezhnosti) in Kyїv. More information can be found Research A...

In the title compound, C22H24N2O6, the indole ring has a twist conformation and the tetra-hydro-2H-pyran-2-one ring a half-chair conformation. One of the pyrrolidine rings adopts an envelope conformation on the N atom, while the other has a twist conformation; the 'butterfly' angle between their mean planes is 62.98 (11)°. The dioxolane ring adopts a twist conformation and the tetra-hydro-furan...

In the title compound, C(18)H(17)ClN(2)O(2)·C(3)H(6)O, the 4H-pyran ring is nearly planar [maximum deviation = -0.108 (1) Å] and the cyclo-hexene ring is puckered [puckering parameters Q(T) = 0.4596 (17) Å, θ = 55.9 (2)° and ϕ = 226.5 (3)°]. The 4H-pyran ring is approximately perpendicular to the benzene ring [dihedral angle = 84.35 (7)°] and is almost coplanar with the mean plane of the cyclo-...

In the title compound, C(20)H(22)O(5), an S(6) ring motif is formed by an intra-molecular C-H⋯O hydrogen bond, which contributes to the stabilization of the mol-ecule. In the xanthene system, the cyclo-hexane ring adopts a chair conformation, the cyclo-hexene ring adopts a half-boat conformation and the tetra-hydro-pyran ring adopts a half-chair conformation. The mean plane of the four essentia...

The title salt, C18H21FNO2 (+)·Br(-), determined at 115 K, crystallizes in the triclinic space group P1. The previously reported polymorph occurs in the monoclinic space group P21 and has two independent mol-ecules in the asymmetric unit [Peeters et al. (1993 ▶). Acta Cryst. C49, 2157-2160]. In the title molecule, the pyran rings adopt half-chair conformations. The absolute configuration is S f...

In the asymmetric unit of the title compound, C16H14N4O3·C2H6OS, there are two independent main mol-ecules (A and B) and two dimethyl sulfoxide solvent mol-ecules. In mol-ecule A, the pyran ring is in a flattened sofa conformation, with the sp (3)-hydridized C atom forming the flap. In mol-ecule B, the pyran ring is in a flattened boat conformation, with the sp (3)-hydridized C atom and the O a...

In the title compound, C22H13BrN2O7·CHCl3, the pyran ring adopts a shallow sofa conformation with the C atom bearing the bromo-chromene system as the flap [deviation = 0.291 (3) Å]. The dihedral angle between the pyran fused-ring system (all atoms; r.m.s. deviation = 0.032 Å) and the bromo-chromene ring system (r.m.s. deviation = 0.027 Å) is 87.56 (9)°. An intra-molecular N-H⋯O hydrogen bond cl...

In the title compound, C(19)H(20)N(2)O(6), the pyrone and pyran rings adopt envelope conformations with the same common C atom as the flap, the dihedral angle between the planes of the remaining ring atoms being 68.27 (4)°. The planar atoms of the pyran ring and the diaza-cyclic ring are almost coplanar, the dihedral angle between their mean planes being 3.29 (7)°. Moreover, the planar atoms of...

An efficient sodium bismuthate (NaBiO3) synthesis of biologically active spiro[4H-pyran]derivatives has been accomplished via one-pot three-condensation of isatin/acenaphthequinone, malononitrile and different reagents including 1,3-dicrbonyl compounds, α-naphthol and 4-hydroxycumarin under solvent-free conditions. The notable advantages of the present procedure are: eco-friendly, environmental...