A new strategy has been proposed for the synthesis of an array imidazo[5,1-c][1,4]oxazine chemotypes by using a planned aza-Michael addition in 3-CR heteroring-forming, post-cyclization transformation followed intramolecular fused-heterocycles formation process.

For many decades, poly(2-oxazoline)s and poly(2-oxazine)s, two closely related families of polymers, have led the life a rather obscure research topic with only few groups world-wide working them. This has changed in last five to ten years, presumably triggered significantly by very promising clinical trials first poly(2-oxazoline)-based drug conjugate. The huge chemical structural toolbox poly...

An interesting silver(I)-catalyzed, one-pot intramolecular cyclization of epoxide-propargylic esters is described. A variety of 1,4-oxazine derivatives were obtained through a novel domino sequence, including three-membered ring-opening, 3,3-sigmatropic rearrangement, 6-exo-cycloisomerization and subsequent intramolecular elimination in moderate yields under mild conditions.

Efficient intramolecular N/O-nucleophilic cyclization of 2-aryl indoles has been developed to afford the corresponding 2-aza-3-oxaindolines and 3-indolinones in 80-95% yield. The methods provided convenient access to fused imidazo[1,2-c]oxazolidinone, oxazolidine, or tetrahydro-1,3-oxazine cores under mild conditions.

A few facile synthetic pathways for bicyclic aminopyridinol antioxidants are presented. Attachment of a long alkyl chain to the bicyclic pyridinol scaffold was established using ester linkage. Non-substituted pyrrolopyridinols and 1,3-oxazine-fused pyridinols were also synthesized as novel antioxidant scaffolds. Antioxidant activities were measured by a radical clock method and new compounds pr...

The title mol-ecule, C(15)H(20)N(2)O(4), contains a benzene ring fused to an oxazine ring and one tert-but-oxy-carbonyl group bound to the N atom. An intra-molecular C-H⋯O inter-action occurs. In the crystal, mol-ecules are linked through inter-molecular N-H⋯O and C-H⋯O hydrogen bonds.

The title compound, C(16)H(25)NO(2), which was synthesized by a Mannich reaction route, is a rare example of an organic compound containing the six-membered oxazine ring. The ring adopts a chair conformation and the N atom is pyramidal. The N atom serves as a hydrogen-bond acceptor to the phenolic OH group.

In the title compound, C(31)H(25)NO, the oxazine ring adopts a half-chair conformation. The dihedral angles between the phenyl rings and the naphthyl ring system are 70.89 (8), 37.34 (10) and 9.42 (10)°. The crystal structure is stabilized by an aromatic π-π stacking inter-action, with a centroid-centroid distance of 3.879 (3) Å.

The special photochromic mechanism of spiro-oxazine (SO) refers to low thermostability and weak fatigue resistance. High light transmittance biocompatibility are the two advantages polymethyl methacrylate (PMMA), but it does not perform well in terms tensile strength. Here, a new type SO (1-(4'methacryloyloxybutyl)- 3,3-dimethyl-9'-hydroxy- 3H-spiro-naphthyl oxazine) was synthesized introduced ...